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1. ccccesceeeseeeseeeeees 4 26 Parameters for Double Differential Pulse Amperomettry c eee 4 28 Parameters for Triple Pulse Amperometry ccceecceesseesteeee eesse ereere 4 30 Parameters for Bulk Electrolysis with Coulomtery ccccesseeeteeeteeees 4 32 Parameters for Hydrodynamic Modulation Voltammetry cee 4 34 Parameters for Sweep Step Functions 0 0 ccc eceetseetseettteetttesteeese 4 36 Parameters for Multi Potential Steps 0 cccceccceceseceseceeeceeeeeeeeeeeeeeteeesees 4 38 Parameters for Chronopotentiometry ccceseeceeeeceteceseeneeeseeeeeesneeneeees 4 39 Parameters for Chronopotentiometry with Current Ramp ceeeeee 4 4 Parameters for Mulit Current Steps a Pee nen Te eee eee aE aC e Parameters for Potentiometric Sitipping Analysis EA E E notes A 4 44 Parameters for Open Circuit Potential Time sssessseseesessessesesrsesersesssee 4 46 Parameters for Quartz Crystal Microbalance ecceescceeseeeeeeeeeeeenees 4 47 System Command saii e T E ER S 4 48 Hardware Test Command ic udiccsdaneiegssasseanhdste basse aneeanndaeetna arasin anaita esenta 4 51 Chapter 5 Control Menu RUD Commanders ieor ontu n aa aa aiaia a enasi 5 1 Pause Resume Command 3c3 05250 cacetscayestes qetasdclassete cea sav alechatemeedseacaaie cag aiaks 5 1 Stop Run Command eniinn na heen a E na Sues ashe Guclitnaetaya h 5 2 R verse Scan C OITA EW
2. This command has a toolbar button Chapter 7 Data Processing Menu Linear Baseline Correction Command Use this command to visually correct the baseline of the currently active data You can compensate a sloping baseline and shift the DC level of the curve The linear baseline correction command will be activated only once In order to compensate or shift the baseline more than once invoke this command repeatedly This command presents a Baseline Correction dialog box Baseline Correction x To perform baseline correction click the OK button first The mouse cursor now changes to an upper arrow cursor To compensate a sloping baseline press the mouse button at the starting point drag the mouse and extend to the point that forms the baseline When the mouse button is released this line is subtracted from your data The range of compensation in X coordinate is the range at which the line is drawn To shift the DC level use the mouse to draw a horizontal line This line will be the new zero of the curve The DC level shift applies to the whole curve You don t have to draw a line to cover the entire X range If there is more than one segment of data available such as CV data you can choose the set of data to operate on by using the Graph Option command under the Graphics menu The baseline correction command will be activated only once In order to compensate or shift the baseline more than once invoke this command repeat
3. SSF STEP SWV TAFEL TPA Abbreviation of Electrochemical Techniques A C Voltammetry including Phase Selective A C Voltammetry Bulk Electrolysis with Coulometry Chronoamperometry Chronocoulometry Chronopotentiometry Chronopotentiometry with Current Ramp Cyclic Voltammetry Double Differential Pulse Amperometry Differential Normal Pulse Voltametry Differential Pulse Amperometry Differential Pulse Voltammetry Hydrodynamic Modulation Voltammetry Impedance Spectroscopy Impedance Time Impedance Potential Integrated Pulse Amperometric Detection Multi Current Steps Amperometry i t Curve Linear Sweep Voltammetry Normal Pulse Voltammetry Open Circuit Potential Time Potentiometric Stripping Analysis Quartz Crystal Microbalance Staircase Voltammetry Second Harmonic A C Voltammetry including Second Harmonic Phase Selective A C Voltammetry Sweep Step Functions Multi Potential Steps Square Wave Voltammetry Tafel Plot Triple Pulse Amperometry Appendix Model 400A Time Resolved Electrochemical Quartz Crystal Microbalance The quartz crystal microbalance QCM is a variant of acoustic wave microsenseors that are capable of ultrasensitive mass measurements Using a crystal with a 7 995 MHz fundamental frequency as used in our measurements as an example a net change of 1 Hz corresponds to 1 34 ng of materials adsorbed or desorbed onto the crystal surface of an area of 0 196 cm QCM and the combinat
4. IV Baseline IV Baseline Y Grid Help JV Param M Param Invert V Result M Result T Y Invert I X Freeze for To bz Cursor Lock to Data Points J Y Freeze 450005 To 35e005 F Lock Free J x Title siz Unit I Current Density T Y Title poo Unt Electrode Area i X Scale 1 Y Scale IM E ys Reference Electrode Segments 1 To 2 Ref Electrode Ag AgCl Header 0 5 mM Ferrocene in 0 1M LICIO4 CH3CN 2mm Pt disk Note The following options allow you to select graphic plot options Screen You can selectively turn on or off header axis baseline parameters and results on the screen The header is the caption shown on top of the plot The header text can be typed in the Header text area The baseline is drawn to visually define a peak or wave The screen options are independent of printer options as described below Printer You can selectively turn on or off header axis baseline parameters and results on the printer The printer options are independent of screen options as described above Chapter 6 Graphics Menu Grid and Inv You can selectively turn on or off XY grid and XY inversion XY inversion will allow you to change the X Y axis polarity This is only for temporary If you want to invert the X Y axis polarity permanently use the System command in the Setup menu XY Freeze You can freeze the XY axis by checking the item s and enter the freezing scale X and Y axis can be c
5. QCM 3Eledrnde Figure 2 3 QCM with temperature control Some Useful Software Tips If you are familiar with Windows applications you may not have any problem to use the instrument Most of the following tips are for users who do not have much experience with Windows However some of the tips could be helpful to every one 2 6 Chapter 2 Getting Started l You should get familiar with the toolbar a bar with many buttons under the main menu bar The toolbar provides quick access to the most commonly used commands To know the meaning of the command buttons click the button and read the comments at the left lower corner of the screen 2 To select multiple filenames for multiple file printing overlay or parallel plots click the first filename you want to select drag the mouse down while holding the left button you will select successive files If the files are scattered in the directory you can select them by holding the Ctrl key while click each filename 3 If you see that the Y axis title is in wrong direction you can use the Font command under the Graphics menu to change the rotation angle of Y axis for printing 4 To select a file or a technique you can double click the item It is equivalent to click the item and then click OK 5 To change the parameters you can use the TAB key to go through each items The text in the edit box will be highlighted You can directly type the new text Sometimes it is much more c
6. The browse button allows user to choose the base filename from different directory 5 6 Chapter 5 Control Menu Data Averaging When Done When this item is checked the data of repetitive runs will be averaged and saved as filename0 5 7 Chapter 5 Control Menu Multiplexer Command Use this command to run a series of experiments using multiplexer The hardware requirement is the CHI684 Multiplexer The minimum channel for the CHI684 is 8 The channel increment is 8 The maximum channels are 64 The multiplexer switches four lines working sensing reference and counter electrodes You can have maximum 64 cells but only one cell can be connected at a time This command presents a Multiplexer dialog box r Channel Selection OK ViM2wW3 M4 M5 WME M Meg gs 8 8 go 8s ww SN De e Help ee Run Multiplexer gs 8 8 8 8 8 Bt Dar ar 43f 440 a0 as ar 48 asl sor 51 527 537 547 557 56 rose ser ssf eor 61f e627 637 64 Cancel int r Prompt Before Each Run m Immediate Channel Set None C Manual Extemal Trigger Channel fi Base Filename Tesi Browse Set The following options allow you to define parameters for repetitive runs Channel Selection You can select any channel by checking that channel Uncheck any channel will disable it If you select a channel that is beyond your CHI684 channel number it will be ignored Prompt Before Each Run When Manual is selected a pro
7. bin binary data file is available Drives Select the drive in which you want to list the file s Directories Select the directory in which you want to list the file s 3 5 Chapter 3 File Menu Convert to Text Command Use this command to convert a binary data file to a text file The text format can be altered with the Text File Format command Multiple files can be selected for conversion To select multiple files point the mouse cursor to the filenames you want to select and click the left mouse button while holding the Ctrl key The text file can be read by other commercial softwares such as spread sheet and data base handlers This command presents a File Conversion dialog box File Conversion IMPE2 J IMPE3 OCPT1 IMPE4 PSAD gt l File name fbin Files of type Data Files bin x Cancel The following options allow you to specify the name and location of the binary file s you re about to convert to a text file File Name Type or select the filename s you want to list This box lists files with the extension you select in the List Files of Type box Multiple files can be selected for conversion You don t have to type the extension The system will automatically attach an extension of bin to the filename Other extensions are not allowed List Files of Type Select the type of file you want to convert Only bin binary data file is available Drives Select the drive
8. 10 step potential 2 in SSF and STEP es3 10 10 step potential 3 in SSF and STEP es4 10 10 step potential 4 in SSF and STEP es5 10 10 step potential 5 in SSF and STEP es6 10 10 step potential 6 in SSF and STEP st1 0 10000 step time 1 in STEP st2 O 10000 step time 2 in STEP st3 0 10000 step time 3 in STEP st4 0 10000 step time 4 in STEP Chapter 5 Control Menu st5 st6 10000 step time 5 in STEP 10000 step time 6 in STEP oo Chapter 5 Control Menu Open Circuit Potential Command Use this command to measure the open circuit potential The open circuit potential is the potential between the working electrode and reference electrode while no current flows through the cell This is an important parameter It tells you what is the initial state before you start experiment You can then figure out if the compound under study is oxidizable or reducible After the measurement the system will display the open circuit potential value through the Open Circuit Potential dialog box Click OK to close the dialog box after you read it Open Circuit Potential Measurement Ea Open Circuit Potential V fi 210 Chapter 5 Control Menu iR Compensation Command Use this command to test the solution resistance and the cell time constant as well as to enable or disable automatic or manual iR compensation This command presents an iR Compensation dialog box iR Compensation x i
9. 2 00E 10 4 00E 10 6 00E 104f 8 00E 10 i A Other Features Windows based software Amperometric and potentiometric detection Constant height and constant current mode Real time absolute and relative distance display Real time probe and substrate current display Current vs X plot Current vs Y plot Current vs Z Plot Applications Electrode surface studies Corrosion Biological samples Solid dissolution Liquid liquid interfaces Membranes Probe Approach Curve Distance um Appendix Model 1000 Series Multi Potentiostat CHII0xx series is a computerized 8 channel potentiostat The system contains a digital function generator a multiplexed data acquisition circuitry a multi potentiostat with eight working electrodes one common reference electrode and one common counter electrode The instrument is designed so that eight working electrodes are in the same electrochemical cell The potential control range is 3 276 V for the primary channel and 2 0 V for the rest of the seven channels Any of these seven channels can also be set at the identical potential as the primary channel with potential range of 3 276 V so that they can sweep or step potentials together with the primary channel Each electrode can be individually controlled including on off control potential and sensitivity settings However the primary channel is always on during ran The current range is 10 mA The instrument is capable of measuring curren
10. 32 Data storage interval Number of Segments 1 1000000 Number of half cycles Current Switching Priority Potential or Time Current polarity switching control Auxiliary Signal Recording Check or Uncheck Simultaneously external signal recording when the sample interval is greater than 0 005 s QCM On Check or uncheck EQCM enable 4 39 Chapter 4 Setup Menu Notes 1 Cathodic current is for reduction and anodic current is for oxidation During the course of reduction if the Low E limit is reached the current polarity will be automatically switched to anodic Similarly if the High E Limit is reached during oxidation process the current will be automatically switched to cathodic The number of current polarity switching depends on the Number of Segments When the number of segments is reached the experiment stops 2 The initial current polarity is determined by the Initial Polarity parameter 3 During the experiment the data will be updated in a rate same as data storage interval 4 In general the data storage interval should be chosen according to the length of the experiment The longer the experiment the larger the data storage interval Whenever the data exceed the maximum allowed points the data storage interval will be doubled automatically Therefore data points will not overflow for an unexpected long experiment 5 Though large number of segments is possible the data will be stored only for first 400 segments The
11. Check the Save retrieve data during run option If you want to retrieve the last run data do it before you start a new run otherwise the data will be lost Update Instrument Software Command Use this command to update the software on the instrument side Only certain instrument models have this command If your instrument has this command please check the Instructions of Software Update Appendix of this User s Manual 3 4 Chapter 3 File Menu List Data File Command Use this command to list a data file in a text mode The text format can be altered with the Text File Format command The current data remains unchanged To view the numerical list of the current data execute the Data Listing command under the View menu This command presents a List Data File dialog box List Data File 2 xi Look in a chi6 e c E IMP1 ITO IMPE1 Lsvo IMPE2 NPVO IMPE3 OCPT1 IMPE4 PSAQ I Files of type Data Files bin x Cancel p A The following options allow you to specify the name and location of the file you re about to list in a text mode File Name Type or select the filename you want to list This box lists files with the extension you select in the List Files of Type box You don t have to type the extension The system will automatically attach an extension of bin to the filename Other extensions are not allowed List Files of Type Select the type of file you want to list Only
12. From ft To fo Help From fo To fo View Baseline From fo To jo View Difference m Baseline Fitting Algorithm and Orders Baseline Fitting Orders E Orthogonal L S C Least Square m Save to Override Original Data NoAction Difference Baseline If there is more than one segment of data available such as CV data you can choose the set of data to operate on by using the Graph Option command under the Graphics menu The following options allow you to select the fitting parameters and the way of the data will be saved Two sides of Peak Foot When fitting the baseline the data points corresponding to peaks should be ignored You need to provide the two sides of the peak foot If the baseline fitting is not ideal you may need to adjust the peak foot values or the polynomial orders 7 7 Chapter 7 Data Processing Menu If there are several peaks you may need to enter several sets of peak feet You can also specify the whole potential or time range that you do not want to use for the baseline fitting A maximum 5 sets of peak feet can be entered Baseline Fitting Algorithm and Orders You also need to specify the algorithm and orders of fitting There are two fitting algorithms used Orthogonal Least Square or Least Square Both are based on polynomial fittings The order of polynomials is related to the shape of the baseline First order stands for linear fitting aX b Second order stands for aX b
13. Inductor L Zp_ joL Y j L 7 2 Warburg Impedance W Zw 1 Yo j Yw Yo ja o n 4 Constant Phase Element Q Zgo 1 Yo jo Yo Yo j p nr 2 0 lt n lt 1 Appendix Cables and Connections 1 Comm Port connection DB 25 connector Pin Function 2 Receive 3 Transmit T Digital Ground 2 Cell Control connection DB 25 connector Pin Function 1 Difference Frequency Input 2 3 4 Analog Ground 5 15V lt 20 mA load 6 5V lt 100 mA load 7 Digital Ground 8 Stir active level can be set in Cell Control 9 Knock active low pulse 10 External Device Sense 1 11 External Device Sense 2 12 External Device Control 1 13 External Device Sense 3 14 Reserved 15 Reserved 16 17 15V lt 20 mA load 18 19 External Device Control 2 20 External Device Control 3 21 Purge active low level 22 23 External Device Control 4 24 External Device Control 5 25 External Device Control 6 The Cell Control port can be used to control stir knock and purge Please check the manual of your cell stand for compatibility Customized jumper or connection cable might be needed Also used for external trigger input TTL signal active low Appendix 3 Electrode connection Video connector Pin Function 1 Working electrode Green 2 Sensing electrode Black 3 Reference electrode White 4 Counter electrode Red 5 Analog Ground z This electrode is used for 4 electrode configuration
14. QCM On box in CV LSV CA i t and CP parameter dialog box You also need to connect the oscillator box to the Cell Control port on the rear panel of the instrument Two contact pins from the oscillator box should be connected to the crystal holder of the EQCM cell The one with green mark is for working electrode It should be connected to the left pin of the crystal working electrode The EQCM cell consists of three round Teflon pieces The total height is 37 mm with a diameter of 35 mm The top piece is the cell top to hold reference and counter 2 3 Chapter 2 Getting Started electrodes There are also two 2mm holes for manual purging The center piece is the cell body for solution The bottom piece is for mounting purpose Four screws are used to tight the bottom piece and center piece together Do not over tight the screws to avoid damage of the screw threads The quartz crystal is located between the center and bottom pieces The seal is through two O rings that are pressed together by the four screws mentioned above The diameter of the quartz crystal is 13 7 mm The gold electrode diameter is 5 11 mm Since CHI400A used time resolved mode the frequency difference of the working crystal and the reference crystal is measured The reference crystal has an oscillation frequency of 8 000M Hz the working crystal oscillation frequency should be 7 995MHz 7 950M Hz The QCM experiment relies on the calculation of mass change Am at the
15. Rotate between Run The following options allow you to set the rotating disk electrode control Rotation Speed rpm This parameter set the speed of the rotating disk electrode The parameter range is 0 10000 There are banana jacks on the rear panel of the instrument that will output a0 10 V voltage that corresponds to 0 10000 rpm rotation rate Rotate during Deposition Time Check this item will turn the rotator on during the deposition time in the stripping analysis This item can also be turn on or off from Run Status command under Control menu Rotate during Quiet Time Check this item will turn the rotator on during the quiet time This item can also be turn on or off from Run Status command under Control menu Rotate during Run Check this item will turn the rotator on when experiment is running This item can also be turn on or off from Run Status command under Control menu Rotate between Runs Check this item will turn the rotator on between runs This item can also be turn on or off from Run Status command under Control menu Chapter 5 Control Menu Stripping Mode Command Use this command to enable of disable the stripping mode and set the deposition condition The stripping mode command is only available to LSV SCV DPV NPV SWV ACV and SHACYV It is also not available if a polarographic mode is chosen This command presents a Stripping Control dialog box Stripping Control Ed jode Enabled IV Purge During Dep
16. The current at the end of each pulses are recorded as the function of time During the experiment only the difference of two current samples is displayed After experiment the current responses to the two potential pulses are also available for display The following diagram shows the potential waveform applied as the function of time and the current sampling scheme Data Sampling Data Sampling paw 2 Clean E1 5 A Clean E2 FA 5 i f El 5 E2 2 Init E E3 E4 Clean T1 Tl T2 Clean T2 T3 T4 Cycle 1 Cycle 2 Time s The following are the experimental parameters their range and descriptions Parameters Range Description First DPA Cleaning E1 V 10 10 Electrode cleaning potential Cleaning Time sec 0 32 Electrode cleaning time Pulse E1 V 10 10 First pulse potential Pulse T1 sec 01 32 First pulse time Pulse E2 V 10 10 Second pulse potential Pulse T2 sec 1 32 Second pulse time Open Circuit During Check or Cleaning step 1 could be either held at Cleaning Uncheck a constant potential or open circuit Second DPA Cleaning E2 V 10 10 Electrode cleaning potential Cleaning Time sec 0 32 Electrode cleaning time 4 28 Chapter 4 Setup Menu Pulse E3 V 10 10 First pulse potential Pulse T3 sec 1 32 First pulse time Pulse E4 V 10 10 Second pulse potential Pulse T4 sec 01 32 Second pulse time Open Circuit During Check or Cleaning step 2 cou
17. To position the electrode disk in the center is important It will reduce the noise and ease the circuit oscillation If you see noise greater than usual or the circuitry does not oscillate please check the electrode disk position and remount the crystal When you make the contact with two pins please make sure that the socket is insert to the pin properly You insert the socket all the way to the end then pull out the socket a little bit 1 mm to avoid the socket touching the bottom of the crystal holder Please make sure that the two wires that connect to the crystal holder is at a rest position to reduce tension and possible movement For EQCM measurements the green pin of the oscillator box is for the working electrode connection you will only need to connect the reference and counter electrodes You can leave the clips with green cover working electrode and black cover sensing electrode of the electrode leads unconnected Testing The instrument was tested before it was shipped The bin files that come with the disk are the data actually acquired with the particular instrument you received To test the communication between the computer and the instrument start the software and turn the instrument power on Use the Hardware Test command under the Setup menu If a Link Failed message appears you should check the connection and the port setting You can use System command under the Setup menu to see if the port setting
18. but the square of Aw in the above equation Chapter 4 Setup Menu Parameters for Sweep Step Functions In Sweep Step Functions SSF six potential sweeps and six potential steps can be mixed together It is somewhat like a arbitrary waveform generator The following diagram shows the potential waveform applied as the function of time One can skip any segment by default parameter It provides better flexibility for waveform control The current is recorded as function of time For sweep segments it can also be presented as function of potential Segments 7 Isla 10 lin a2 Final E Potential V Init E Scan Rate V s Time s The following are the experimental parameters their range and descriptions Param Range Description Sequence 1 3 5 7 9 11 Sweep Init E V 10 10 Initial potential Final E V 10 10 Final potential Scan Rate V s le 6 50 Potential scan rate Sequence 2 4 6 8 10 12 Step Step E V 10 10 Step potential Step Time s 0 10000 Step Duration Init E V 10 10 Initial potential Sweep S I V 0 001 0 05 Sweep function sample interval Step S I s 0 0001 1 Step function sample interval Quiet Time sec 0 100000 Quiescent time before potential scan 4 36 Chapter 4 Setup Menu Sensitivity A V le 12 0 1 Sensitivity scale Notes 1 For sweep function if the difference of Init E and Final E is less than 0 01 V this se
19. o e e Full version of CV simulator Limited version of CV simulator amp Corresponding stripping mode can be performed Note 1200A 1205A 1207A 1210A 1220A 1230A are single potentiostat 1202A 1206A 1208A 1212A 1222A 1232A are bipotentiostat Appendix CHI200 B Picoamp Booster and Faraday Cage With CHI200 B Picoamp Booster and Faraday Cage the current down to a few picoamperes can be readily measured CHI200 is compatible with Model 600 A 700 A series of instruments CHI200B is compatible with Model 600B C 700B C and 800B series When used with 700 A B C and 800B series bipotentiostat Picoamp Booster will have effect on the primary channel only The internal sensitivity of the 600C series is the same as the Picoamp Booster 1x10 A V However the bias current of the 600C series input can be as high as 50 pA The Picoamp Booster has lower bias current and it also bring the preamplifier close to the electrode that results in lower noise It is also necessary to have Faraday Cage in case of small current yet relatively fast measurements Before connecting the Picoamp Booster turn the instrument power off Connect the din connector of the Picoamp Booster to the Electrodes connector at the rear panel of the instrument Also connect the DB 25 connector of the Picoamp Booster to the Cell Control connector at the rear panel of the instrument with a straight through DB 25 cable come with PBFC You can then turn the po
20. ohm Sensitivity scale 1x107 0 1 A V in 10 ranges Input bias current lt 100 pA Potential update rate 1 MHz Chronopotentiometry with Current Ramp CPCR Potentiometric Stripping Analysis PSA _ Open Circuit Potential Time OCPT e Galvanostat Full version of CV simulator Limited version of CV simulator Appendix Model 1200A Series Hand held Potentiostat Bipotentiostat The Model 1200A series is a computerized hand held potentiostat bipotentiostat The instrument consists of a digital function generator a data acquisition system a potentiostat bipotentiostat The potential range is 2 4 V The current range is 2 mA This series is capable of measuring current down to 100 pA The steady state current of a 10 um disk electrode can be readily measured The size of the instrument is 7 L x 4 5 W x 1 B The instrument is powered by the PC computer through the USB port The instrument can be used for electroanalysis and sensor studies Due to its small size light weight and low cost it is particularly useful for field applications and teaching laboratories The CHI1200A series provides various instrument models to meet different applications and budget The instrument offers potentiostat version and bipotentiostat version The CHI1200A 1210A 1220A 1230A and 1240A are potentiostat whereas the CHI1202A 1212A 1222A 1232A and 1242A are bipotentiostat Specifications Potentiostat bipoten
21. potential for a given amount of time Chapter 5 Control Menu Mercury Drop Collection This is a useful option for you to collect and then weigh mercury drops Enter the number of drop you want to collect range from 1 to 1000 and the time interval between drops range from 0 5 to 10 Press Collect pushbutton will activate the collection process Stir Between Runs Check this item will allow stir between runs This item can also be turned on or off from Run Status command under Control menu Purge Between Runs Check this item will allow purge between runs This item can also be turned on or off from Run Status command under Control menu Reference Crystal frequency Enter the reference crystal frequency This information is used to calculate the mass change SMDE Drops Before Run The default value of this parameter is 1 Normally the system will issue a combined dispense and knock signal before running experiment to allow a new drop to be formed when the static mercury drop electrode SMDE is used You can change this default condition The parameter range is 0 20 If the prerun drop is set at 0 the same drop used in the previous experiment will be used for the next experiment More than one prerun drops might be useful if the SMDE occasionally traps little air bubble in the capillary and loses contact This option can also be changed from Run Status command under Control menu Stabilizing Capacitor There is a 0 1 uF stabilizing
22. terminology that most chemists are familiar with The toolbar allows quick access to the most commonly used commands The help system provides context sensitive help It is systematic and complete The instrument provides many powerful functions such as file handling experimental control graphics data analyses and digital simulation Some of the unique 1 1 Chapter 1 General Information features include macro command working electrode conditioning color legend and font selection data interpolation visual baseline correction data point removing visual data point modification signal averaging Fourier spectrum and equations relating to electrochemical techniques 1 2 Chapter 1 General Information Electrochemical Techniques Sweep Techniques Cyclic Voltammetry Linear Sweep Voltammetry Rotating Disk Electrode Voltammetry Tafel Plot Sweep Step Functions Step Techniques Chronoamperometry Chronocoulometry e Staircase Voltammetry Tast Polarography e Differential Pulse Voltammetry and Polarography Normal Pulse Voltammetry and Polarography Differential Normal Pulse Voltammetry and Polarography Square Wave Voltammetry Multi Potential Steps A C Techniques A C Voltammetry and Polarography Phase Selective A C Voltammetry and Polarography Second Harmonic A C Voltammetry and Polarography Stripping Techniques Linear Sweep Stripping Voltammetry Differential Pulse Stripping Voltammetry Normal
23. Control dialog box OO mmm m Control Level of Stir Line Cancel Help Ref Crystal Frequency Hz Be 006 SMDE Drops Before Run ft m Immediate Purge m Stabilizing Capacitor Purge Time sec 240 IV Automatic Setting Purge On Off e I 4 Electrodes IV Stir Between Run m Immediate Cell On m Mercury Drop Collection MV Purge Between Run Potential V jo Number of Drops 50 I7 Stir and Purge Simultaneously Time sechl fio Time Interval sec fi I Test with Internal Dummy Cell Cell On Collect J Cell On Between Runs IV Return to Init E after Run The following options allow you to set the cell control Control Level of Stir Line The stir line control signal can be either active high or active low BAS uses an active high control signal whereas PAR uses an active low signal You can click the radio button to select the proper control level Immediate Stir You can enter immediate stir time The parameter range is between 1 32767 Press the Stir button will activate immediate stir Immediate Purge You can enter immediate purge time The parameter range is between 1 32767 Press the Purge button will activate immediate purge Immediate Cell On You can enter the cell potential range from 10 to 10 and the cell on time range from 1 to 32767 Press the Cell On button will poise the electrode at the given
24. Control menu You can select any channels and run experiment in a sequence of selected channels The files will automatically saved after each run You can also set prompt before each channel run It is allowed to set arbitrary channel immediately You can run experiment for that particular channel Two Macro commands are available for the multiplexer One is mch It allows to set individual channel The other macro command is mchn This is used in For Next loop It will select the channel according to the For Next loop counter The minimum channels for the CHI684 are 8 The channel increment is 8 The maximum channels are 64 Appendix CHI680 Amp Booster With the CHI680 Amp Booster the current can be measured up to 2A The CHI680 is compatible with Model 600 60A B C series of instruments You can stack the CHI6xx and the CHI680 together Before connecting the Amp Booster turn the instrument power off Connect the 6 pin din connector of the CHI680 to the Electrodes connector on the rear panel of the CHI6xxC Also connect the Cell Control ports of both instruments with a straight through 3 ft DB 25 cable come with the CHI680 You can then turn the power on for both CHI6xxC and CHI680 It is generally a good practice to turn on the CHI6xxA B C first and then CHI680 When the power is turned off reverse the order The cell connector is a 6 pin connector with four cell leads The clip with green cover is for worki
25. Cycles Quiet Time sec 0 100000 Quiescent time before taking data Scales During Run 1 2 3 Number of current display scales Sensitivity A V le 12 0 1 Sensitivity scale Notes 1 The experimental sequence follows first pulse second pulse and third pulse This sequence will be repeated until the total running time is reached or interrupted by user There is no data acquisition during the first and second They are used for electrode cleaning purposes If the first and or second pulse time is zero the corresponding step will be ignored Data is sampled only for the third pulse 2 Ifthe increment potential is non zero the experiment will start at the E3 and end at the Final E E3 and Final E should be at least 0 01 V apart The number of cycles will have no effect 3 The data is sampled at later 2 period of pulse 3 The longer the pulse width the longer the sample interval Long sample interval will have better signal averaging and less noise 4 During experiment whenever the data exceed the maximum allowed points the data storage interval will be doubled automatically Therefore data points will not overflow for an unexpected long experiment 5 When 1 current scale is displayed during run it will automatically fit the data in scale When 2 current scales are displayed during run they is 1 100 and 1 10 of full scale When 3 current scales are displayed during run they is 1 100 1 10 and 1 1 of full scale 4 31 Chapter 4 S
26. Electrode Indicator Description Technique The currently active technique 3 or 4 electrode configuration 10 6 Chapter 11 Help Menu Help Topics Command Use this command to display the opening screen of Help From the opening screen you can jump to step by step instructions on how to use the program as well as various types of reference information Help Topics EC Application Help 2j x Index Find 1 Type the first few letters of the word you re looking for control managing 2 Click the index entry you want and then click Display analysis managin dataproc managing equations exit files managing graphics managing printing and print preview setup managing sim managing status bar toolbar view managing Display Print Cancel There is a Context Help for buttons in the toolbar Use the Context Help command to obtain help on some portion of the program When you choose the toolbar s Context Help button the mouse pointer will change to an arrow and question mark Then click anywhere in the application window to obtain help on the item you ve picked Chapter 11 Help Menu About Command Use this command to display a copyright notice the version number the software revision date and the manufacturer s contact information CH Instr CHI Version 5 07 revised on 4 12 2005 Copyright 1994 2005 by CH Instruments Inc 3700 Tennison Hill Drive Austin TX 78738 5012
27. Equations Command Use this command to view the equations relating to the electrochemical technique currently invoked The following is a list of equations available For more details about the equations and how to use them please refer to Electrochemical Methods A J Bard and L R Faulkner Wiley New York 1980 Equations General equations Symbols and Units Linear Sweep Voltammetry and Cyclic Voltammetry Staircase Voltammetry Tafel Plot Chronoamperometry Chronocoulometry Differential Pulse Voltammetry Normal Pulse Voltammetry Square Wave Voltammetry A C Voltammetry 2nd Harmonic A C Voltammetry i t Curve Bulk Electrolysis Hydrodynamic Modulation Voltammetry A C Impedance Chronopotentiometry Potentiometric Stripping Analysis 10 4 Chapter 10 View Menu Clock Command Use this command to view the current date and time This command presents a Clock dialog box so you can view the date and time The time will be updated constantly Clock Date fi 5 Dec 2001 Time fis 37 07 10 5 Chapter 10 View Menu Toolbar Command Use this command to display and hide the Toolbar which includes buttons for some of the most common commands in the system such as File Open A check mark appears next to the menu item when the Toolbar is displayed The toolbar is displayed across the top of the application window below the menu bar The toolbar provides quick mouse access to many tools used in the program To h
28. In this case when the Present Data Plot command under the Graphics menu is invoked the original data reappears This command has a toolbar button 7 2 Chapter 7 Data Processing Menu Derivatives Command Use this command to calculate the derivative of the currently active data After performing a first order derivative the Y axis has a unit of Y unit X unit For voltammetry it is A V For an i t curve it is A s The new unit is not explicitly expressed but you should be aware of it This command presents a Derivative dialog box I x Derivative Order OK 1st Order Derivative Cancel 1st Order Derivative 2nd Order Derivative 3rd Order Derivative Help 4th Order Derivative 5th Order Derivative Least Square Point 7 IV Override Present Data lt To calculate the derivative click the OK button The following options allow you to select the order and parameter for derivative Order Selection Select the derivative order first second third fourth or fifth order Least Square Point The Savitzky and Golay algorithm is used to calculate the derivative An odd number of points from 5 to 49 should be used Since the derivative tends to amplify high frequency noise a relatively large number of points should be considered The more the points the less noisy the derivative data will appear but it may cause larger distortion For more detail about the Savitzky and Golay algorithm please see Smoothi
29. It can be used for liquid liquid interface measurements In this case the red clip is connected to the counter electrode in phase I The white clip is connected to the reference electrode of the same phase The green clip is connected to the counter electrode in phase II The black clip is connected to the reference electrode of phase II The 4 electrode configuration also helps to eliminate contract resistance due to clip connector switching relay and the resistance of circuitry traces It is very important for large current gt 100mA measurements and low impedance cell lt 1 ohm However it is not recommended for low current measurement lt 100mA and high impedance cell To use 4 electrode configuration please check the 4 Electrode option use the Cell command under the Control menu If the purpose of using the 4 electrode configuration is to eliminate contact resistance you should connect the Sensing electrode together with the Working electrode If you do not use 4 electrode configuration please make sure that the 4 Electrode option in Cell Control dialog box is unchecked Otherwise noise and other problems may occur If you use 3 electrode configuration please leave the Sensing electrode unconnected 4 RDE Control connection Banana jacks Red Signal Black Analog Ground 5 Signal Output on Rear Panel 9 pin D connector l Current Output 2 Potential Output 3 External Signal Input 4 External Potential Input 5
30. M Report Filename Enter the report filename if you want to save the report text file If the name already exists an override warning will be issued If no filename is specified the report will be shown but not saved Report Data Type You can report concentration or peak current Header This is the header text editor box Enter your header here To display the header on top of the plot check the Header box using the Graph Option command Note This is the note text editor box Enter your note here The note will be saved in the data file It allows you to put more comments about the data and remind you later about the purpose and the conditions of the experiment Read Use this command to read the data you saved Save Use this command to save your data XY titles units header and note will be saved along with the data Report Use this command to generate the data file report 8 6 Chapter 8 Analysis Menu Time Dependence Command Use this command to generate a report or plot for time dependence of peaks or concentrations from stored data files This command reads data from stored files and searches for peaks The peak height or concentration will be used for the time dependence report All the valid data files i e containing the peak specified are sorted according to the experiment run time The first one is assigned to the start time The time of the other experiments are obtained by subtracting the start time The system d
31. Parameters for Quartz Crystal Microbalance For details of the parameters of each technique see the description of individual dialog box of related techniques This command has a toolbar button Chapter 4 Setup Menu Parameters for Cyclic Voltammetry In Cyclic Voltammetry CV potential is scanned from Init E toward either High E or Low E depending on the Init P N The potential will then scan back The following diagram shows the potential waveform applied as the function of time The current is recorded as the function of potential High E Scan Rate V s Potential V Init E Segment 1 Segment 2 Low E Segment 3 Time s The following are the experimental parameters their range and descriptions Parameters Range Init E V 10 10 High E V 10 10 Low E V 10 10 Init P N Positive or Negative Scan Rate V s le 6 2000 Sweep Segments 1 1000000 Sample Interval V 0 001 0 064 Quiet Time sec 0 100000 Sensitivity A V le 12 0 1 Auto Sens if Scan Rate Check or Uncheck lt 0 01V s Scan Complete Cycles Check or Uncheck Auxiliary Signal Check or Uncheck Recording Description Initial potential High limit of potential scan Low limit of potential scan Initial scan direction Potential scan rate Sweep segments each segments is half cycle Data sampling interval Quiescent time before potential scan Sensitivity scale Automatic sensitivity switching during
32. Pulse Stripping Voltammetry Square Wave Stripping Voltammetry A C Stripping Voltammetry Phase Selective A C Stripping Voltammetry Second Harmonic A C Stripping Voltammetry Controlled Current Techniques Chronopotentiometry Chronopotentiometry with Current Ramp Potentiometric Stripping Analysis Other Techniques Amperometric i t Curve Differential Pulse Amperometry Chapter 1 General Information Double Differential Pulse Amperometry Triple Pulse Amperometry Bulk Electrolysis with Coulometry Hydrodynamic Modulation Voltammetry Open Circuit Potential Time Quartz Crystal Microbalance Chapter 1 General Information Software Features User Interface 32 bit Windows application with multi document interface toolbar quick access to the most commonly used commands status bar technique file status and command prompt pull down menus dialog boxes e full mouse support WYSIWYG graphics comprehensive and context sensitive help File Management open data files save data file delete files e list data file convert to text files for exporting data to other software such as spreadsheet text file format print present data print multiple data files print setup Setup technique full repertoire of electrochemical techniques experimental parameters extremely wide dynamic range system setup communication port polarity of potential and current axis hardware test digital and analog circuitry dia
33. Reactions A e B ko W Eo 0 2 alpha jos Cancel C e D 0 01092 Eo 0 49566 alpha os H Help B D D C B 738e 006 kb Determined kol A C kf 7 78867 kb 0 3894 kf kf 778800 kb Determined On the left side of the panel the reaction mechanism is listed This will remind you of each step On the right side of the panel either 2 or 3 parameter boxes are shown depending on the type of reaction considered Enter the proper value into the edit box If the reaction involves an electron transfer enter the heterogeneous rate constant ko the standard redox potential Eo and the charge transfer coefficient alpha If a chemical reaction is involved enter the forward and backward rate constants for this reaction Sometimes you may notice that some of the kinetic parameters are predetermined This because the concentrations of n species can be determined by n 1 reactions plus the initial conditions It often occurs that there are more equations than the number of species Therefore some of the equations must be linearly correlated The equilibrium constants of some reactions are overdetermined and should not be assigned arbitrarily otherwise the system will never be able to reach an equilibrium The software will look for such dependences and properly assign the kinetic parameters Put the reactions whose kinetic parameters you know best on the top and those you know less accurately at the bottom and let the software determine the pro
34. Selftest dialog box Hardware Test Results xi g Digital circuitry test results ROM version 1 04 ROM revision date 18 Jul 2003 Help Check Code 0 0 Potential and current offset test OK Sensitivity test OK Gain stages test OK Analog circuitry test OK Digital Circuitry Test The software version and the last revision date for the Flash ROM is shown Potential and current offset test If test is failed the error message will be given Sensitivity scale test If test is failed the error message will be given Most times the error is related to leakage current Gain test There are 3 gain stages If test is failed the error message will be given Analog Test Summary The test results of analog circuitry are summarized A message of Analog circuitry test OK will appear if no error is detected otherwise an error message will appear In case there is error and the cause is due to the analog to digital converters it will also be reported If you see analog test error please repeat the test several times and see if the error is consistent Record the error message and contact the factory for servicing Chapter 5 Control Menu Run Command Use this command to run experiment Before run the instrument will check the data link If link fails the command is terminated and an error message will appear The software will also check the combination of experimental parameters If illegal combin
35. Text Display Enabled the text you enter will remain but will not be displayed You can alter the existing text its position or rotation angle or simply erase it You need to move the mouse close to the upper left corner of the first letter of the text Double clicking that location will select the existing text You can change the setting If you clear the Text field the existing text will be gone when you exit the dialog box The entered text will also be saved with the data when you save the data file Depending on the techniques the data can be displayed in various formats Technique Data Display Formats CV sweep segment TAFEL log current potential current potential current density potential CA i t iot CC Q t Q ue SWV forward current reverse current forward and reverse current difference of forward and reverse current sum of forward and reverse current forward reverse and summation current forward reverse and difference current 6 2 Chapter 6 Graphics Menu ACV PSACV BE IMP IMP t or IMP E IMP E CP PSA absolute current phase selective current resistance capacitance absolute current phase selective current resistance capacitance charge time current time current log time Bode log Z log freq Bode phase log freq Bode log Z amp Z log freq Bode log Y log freq Nyquist Z Z Admittance Y Y Warburg Z amp Z w ZL
36. Uncheck Notes 1 Init E and Final E should be at least 0 01 V apart 2 The maximum potential scan range is 13 1V 3 The potential increment is 0 1 mV if the scan rate is below 100 V s The potential increment is 1 mV at the scan rate of 1000 V s and 2 mV at 2000 V s 4 The sample interval can be 1 mV When the scan rate is below 200 V s The sample interval is 2 mV at the scan rate of 400 V s and 10 mV at 2000 V s If the scan rate is high the data sampling interval will be automatically increased 5 When scan rate is below 0 01 V s the sensitivity scale during run can be automatically switched according to the current level When it is activated the sensitivity selection will have no effect on the measurement However the automatic sensitivity switching range will be from 1e 8 0 1 A V instead of le 12 0 1 A V In order to select higher sensitivities automatic sensitivity switching option needs to be disabled 6 Ifthe scan rate is lower than 0 5V s it is possible to record external voltage signal such s spectroscopic signal simultaneously with the voltammogram Use the 9 pin D connector on the real panel for signal input Check the User s Manual for the pin out and signal level requirements 7 When the noise level is high particularly line frequency noise lower resolution with signal averaging sample many times during the sample interval works better However if noise is not a problem high resolution ADC provide bett
37. Wh itl a Report Data Type Conc C Current Header Waste Water Batch 16 Note The following options allow you to enter the peak potential windows slope and intercept of calibration curves and select the data files for report Compound Enter the names of the determined compounds A maximum of four compounds can be searched and reported Ep From and Ep To Enter the peak potential range Ep From and Ep To cannot be equal When the program searches for peaks the first peak in the specified range will be selected For a different compound different values should be entered Slope Enter the slope of the calibration curve for the compound It will be used to calculate the concentration of the compound Each compound has its own slope If Conc report is selected and the slope is zero a warning will be given Intercept Enter the intercept of the calibration curve for theat compound It will be used to calculate the concentration of the compound Each compound has its own intercept Peak Shape You can select the peak shape according to the property of your data The peak shape can be Gaussian diffusive or sygmoidal 8 5 Chapter 8 Analysis Menu Data Type You can select original data semi derivative or first derivative to report the concentration Number of Species Enter the number of species for the data file report Concentration Unit Enter the concentration unit or dimension such as ppm or
38. are not allowed List Files of Type Select the type of file you want to print Only bin binary data file is available Drives Select the drive from which you want to print the file s Directories Select the directory from which you want to print the file s Chapter 3 File Menu Print Setup Command Use this command to select a printer and a printer connection This command presents a Print Setup dialog box 2x Printer Name HP LaserJet 4050 PCL amp Properties Status Default printer Ready Type HP Laserdet 4050 Series PCL 6 Where LPT1 Comment Paper Orientation Size Letter Portrait Source Auto Select Q Landscape Cancel The following options allow you to select the destination printer and its connection Printer Select the printer you want to use Choose the Default Printer or choose the Specific Printer option and select one of the currently installed printers available in the box You can install printers and configure ports through the Windows Control Panel Orientation Choose Portrait or Landscape The paper orientation has to be landscape in the CHI program environment If a warning pops up use the Print Setup command to set the paper orientation properly This setting will however not be saved once you quit the program In order to set the paper orientation to landscape permanently you need to set the printer to Landscape globally by changin
39. area e manual results visually selected baseline peak definition shape width and report options X Y Plot for your own data points peak parameter plot iy v iv Ep log v plots semilog plot current potential semilog plot graph options video or printer options axis parameters baseline results grids axis inversion axis freeze axis titles data sets XY scales reference electrode header and notes color and legend background axis grid curves legend size thickness and display intervals e font font style size and color for axis labels axis titles header parameters and results e copy to clipboard for pasting the data plot to word processors Data Processing e smoothing 5 49 point least square and Fourier transform e derivatives 1st 5th order 5 49 point least square e integration convolution semi derivative and semi integral interpolation 2x 64x data interpolation baseline fitting and subtraction selectable fitting function polynomial order and potential range for best fitting and baseline subtraction particularly useful for trace analysis e linear baseline correction visually selected baseline slope and dc level compensation e data point removing 1 6 Chapter 1 General Information data point modifying visual data point modification background subtraction difference of two sets of data signal averaging averaging multiple sets of data mathematical operations both X and Y data array e Fouri
40. be performed amp Corresponding stripping mode can be performed Dynamic Range of Some Experimental Parameters for Model 800B Series Parameters Range Techniques Involved Potential V 10 to 10 Current A 0 to 40 010 Sensitivity A V 1x10 to 0 001 Scan rate V s 0 000001 to 25 Pulse width sec 0 001 1000 Pulse width sec 0 001 to 10 Sampling Interval sec 00005 to 100 Frequency Hz 1 to 10000 Model 8xxB Single 8x0B or dual 8x2B channel electrochemical detection High sensitivity and low noise Fast 16 bit A D converter and 24 bit high resolution A D converters Bipotentiostat can also be used for RRDE The Model 800B is the upgrade version of the Model 800 and 800A series It is more sensitive than the 800 series and has wider potential range New features include high data acquisition rate iR compensation current re zeroing circuitry low pass filters with lower cutoff frequencies 0 10V RDE control output and galvanostat model 840B 842B Appendix CHI900B 910B Scanning Electrochemical Microscope The scanning electrochemical microscope SECM was introduced in 1989 as an instrument that could examine chemistry at high resolution near interfaces It is based on reactions that occur at a small electrode the tip as it is scanned in close proximity to a surface SECM can be employed to obtain chemical reactivity images of surfaces and also in quantitative measurements of reaction rates Numerous
41. bin binary data file is available 3 Drives Select the drive in which the file is stored Directories Select the directory in which the file is stored This command has a toolbar button u E 3 1 Chapter 3 File Menu Save As Command Use this command to save and name a file This command presents a Save As dialog box IMPE1 IMPE2 NPVO IMPE3 OCPT1 IMPE4 PSA0 gt Save as type Data Files bin z Cancel Z The following options allow you to specify the name and location of the file you re about to save File Name Type a new filename to save the current data and many variables A filename can contain up to eight characters If an existing filename is used the system will display a warning and then proceed You don t have to type the extension the system will automatically attach an extension to the filename For a data file the extension is bin binary file For a macro file the extension is mcr For a simulation file the extension is sim Other extension is not allowed List Files of Type Select the type of file you want to open Only bin binary data file is available Select the drive in which you want to store the file Directories Select the directory in which you want to store the file This command has a toolbar button 3 2 Chapter 3 File Menu Delete Command Use this command to delete files This command presents a File Deletion
42. capacitor that might be connected between the counter and reference electrodes This capacitor can stabilize the potentiostat but somewhat slow the system down This is particularly useful when the double layer capacitance of working electrode is large such as in bulk electrolysis or in case high degree of iR compensation is required The default for this stabilizing capacitor is automatic setting You can disable the automatic setting and then enable or disable the stabilizing capacitor by clicking one of the radio buttons 4 Electrodes Check this will set the potentiostat at 4 electrode configuration The 4th electrode is used for sensing the voltage drop due to the contact resistance of electrode clip connector relay and circuit board traces The contact resistance could be about 0 2 0 3 ohm It can cause 50 75 mV voltage drop if the current is at 250 mA It also makes low impedance cell such as battery measurement impossible With the 4th electrode introduced the effect of contact resistance can be eliminated and low impedance cell can be readily measured You should turn the 4th electrode off if you have a cell that has relatively large impedance 10 ohm or above Test with Internal Dummy Cell 5 20 Chapter 5 Control Menu Internally there is a 1K ohm resistor as dummy cell When this option is checked the cell will not be turned on instead the internal dummy cell will be used to run experiment This option is useful f
43. clicking it The component s color will change to red Then click the Cut button on the toolbar When a component is deleted the corresponding connections are deleted with it You can also remove a component by moving the mouse to the component holding down the left button and dragging it out of the edit field To remove a connection wire select the wire by clicking the trace will turn to red and use the Cut command on the toolbar You can move components and wires around Select a component or a trace drag it while holding the left mouse button After you move the component or the trace to a desired location release the left mouse button You can thus make the circuit drawing more readable You can use the Move button on the toolbar to move all components left right up or down You can also use the Rearrange button on the toolbar to rearrange components and connection wires However there are only four modes and they may not create an ideal diagram You may have to redraw the diagram manually To finish the equivalent circuit drawing you need to connect the two big dots on the left and the right sides of the edit field If you do not connect those two dots the program will not know what the two terminals of your circuit are and can not perform simulation You might find the command buttons on the toolbar useful You can undo or redo your actions You can clear the edit field by removing all the components and connection wires You c
44. command presents a Preconditioning before Run dialog box Preconditioning before Run x OK m First step Cancel Potential V J fo Help MEE aa jo m Second step Potential V jo Time s o m Third step lt F Electrode 2 Potential fo M Stir On ERER fo Purge On You can program the conditioning in three steps The following options allow you to set preconditioning Enable Preconditioning Preconditioning occurs before the deposition or quiet time Uncheck this box will bypass the proconditioning step Potential The parameter range is between 10 10 Time The parameter range is between 0 6400 If preconditioning time for a particular step is zero this step will be bypassed If the time setting is less than 1 msec the time control may not be accurate Stir On Check this item will turn on stir during preconditioning Purge On Check this item will turn on purge during preconditioning Chapter 5 Control Menu Rotating Disk Electrode Command Model 430A 440A Use this command to set the rotation rate for the rotating disk electrode You can also control the rotator on and off in various cases This command presents a Rotating Disk Electrode Control dialog box Rotating Disk Electrode Control x Rotation Speed rpm 260d J Rotate during DepositionTime Cancel J Rotate during Quiet Time Help l Rotate during Run
45. computerized time resolved electrochemical quartz crystal microbalance They can also be used for general purpose electrochemical applications The system contains a quartz crystal oscillator fast digital function generator a high speed data acquisition circuitry a potentiostat and a galvanostat Model 440A only The QCM is integrated with potentiostat and galvanostat and it makes EQCM study simple and convenient Instead of measuring the frequency directly the frequency signal of the QCM is subtracted from a standard reference frequency The difference is then measured by reciprocal technique This technique greatly reduce the time need to sampling the QCM signal and can give much better time resolution for QCM signal With direct counting method a 1 Hz QCM resolution requires 1 second of sampling time and a 0 1 Hz resolution requires 10 seconds sampling time The time resolved mode allows QCM signal to be measured in milliseconds with 0 1Hz or better resolution The potential control range of the instrument is 10V and the current range is 250mA The instrument is capable of measuring current down to picoamperes The steady state current of a 10 um disk electrode can be readily measured The time scales of most experiments are one or two orders of magnitude shorter than those you can find in other commercial instruments For instance the scan rate in cyclic voltammetry can be up to 100V s with a 0 1mV potential increment or 2000V s with a 2mV
46. dialog box File Deletion 2 x Look in a chi6 e IMP1 ITO IMPE1 Lsvo IMPE2 NPVO IMPE3 OCPT1 IMPE4 PSA0 Ej File name binl Files of type Data Files bin Cancel The following options allow you to specify the name and location of the file you re about to delete File Name Type or select the filename s you want to delete This box lists files with the extension you select in the List Files of Type box To delete multiple files point the mouse cursor to the filename s you want to select and click the left mouse button while holding the Ctrl key The system adds the extension you specify in the Delete Type box List Files of Type Select the type of file you want to delete Drives Select the drive that contains the file s you want to delete Directories Select the directory that contains the file s you want to delete 3 3 Chapter 3 File Menu Retrieve Command Use this command to retrieve data saved on the hard drive during run In case an experiment does not complete due to external interference interruption or miss communication the data can be partially recovered This is useful for very slow experiments Hours of experimental data can be recovered with this command This command is not active by default If you do not run very slow experiments you can re run the experiment if it is accidentally interrupted In order to activate this command use System under the Setup menu
47. e c E EJ MPO IMP1 ITO IMPE1 Lsvo IMPE2 NPVO IMPE3 OCPT1 IMPE4 PSAQ 2 File name CV4BIN CV3 BIN CVZ BIN Files of type Data Files bin Cancel The plot will be scaled according to the currently active data This command does not check the type of data If both X and Y values fall into the plot scale the data point will be plotted The Graph Option Color and Legend and Font commands allow you customize your data plot The color and legend of each trace can be specified by Color and Legend command This command is disabled if there is no currently active data This command is also disabled unless the current plot is an overlay plots Chapter 6 Graphics Menu Parallel Plots Command Use this command to plot multiple sets of data in a parallel mode This is particularly useful to view data obtained with different techniques and for data comparison You can select the data files you want to plot along with the currently active data Multiple files can be selected To select multiple files point the mouse cursor to the filename you want to select and click the left mouse button one at a time while holding the Ctrl key This command will allow you to select multiple files in the same directory In order to parallel plot data from a different directory or from a floppy disk use the Add Data to Parallel command This command presents a Parallel Data Display dialog box IMP
48. evolution of component parameters will be diaplyed When the values stop changing the fitting ends You can then see the fitting results value of component parameters as well as the fitting error In order to stop the fitting process click the Exit button on the toolbar The original data and the fitted data will be overlaid and displayed You can save your equivalent circuit drawing to a disk file and read it back later To exit the circuit editing field click the Exit button You need to exit first to use other commands of the program Notes Before you run the fitting program by pressing the Fit button connect the instrument The program will check for the proper instrument model It only needs to check once after the program is started After the first fit you do not need to have the instrument connected anymore When you do impedance simulation and fitting please do not enter other technique or read data files other than impedance measurements Otherwise the equivalent circuit editing field will go wrong Dimensions and Ranges of Components Name Dimension Range Resistor R Ohms 0 001 lel2 Capacitor C Farad le 12 1 Inductor L Henry le 12 1 Warburg Impedance W Siemensesec le 6 1 Constant Phase Element Q Siemensesec le 12 1000 Chapter 9 Simulation Menu Property of Components Component _ Impedance Conductance Phase Resistor R Zr R Yr 1 R frequency independent Capacitor C Zc j aC Yco joC p n 2
49. for concentration and distance see the two items below Conc Range Enter the concentration scale for the concentration profile display The range is 0 001 to 100000 The default is 1 Dist Range Enter the distance scale for the concentration profile display The range is 0 001 to 10 The default is 1 Time Delay Loop The speed of digital simulation depends on the problem you want to study and the type of computer used If the simulation is performed at a fast speed you may not be able to see the progress or the change in concentration profiles clearly You can insert time delay loops between the computation of two points to slow down the system The range of this parameter is 0 to 1e6 The optimal delay loop duration depends on the problem you want to study and the speed of the computer used Read Command You can read proviously saved sim files These files contain all the parameters needed for a simulation An Open dialog box will be displayed so you can select your file Save Command 9 3 Chapter 9 Simulation Menu You can save all the parameters needed for a simulation to the disk by invoking this command The file will have a sim extension The Save As dialog box will be displayed so you can name your file Exp Param Command Press this button to set the experimental parameters of the simulation You can also change the experimental parameters through the Parameter command under the Setup menu The Cyclic Voltamm
50. freq is 01 1 Hz in IMP cl4 1 256 measuring cycles if 001 01 Hz in IMP cl5 1 16 measuring cycles if 0001 001 Hz in IMP depeon deposition potential on in stripping mode depeoff deposition potential off in stripping mode depe 10 10 deposition potential dept 1 100000 deposition time pcon turn on preconditioning pcoff turn off preconditioning pce 10 10 potential of the 1st stage of preconditioning pce2 10 10 potential of the 2nd stage of preconditioning pce3 10 10 potential of the 3rd stage of preconditioning pct1 0 6400 time of the 1st stage of preconditioning pet2 0 6400 time of the 2nd stage of preconditioning pct3 0 6400 time of the 3rd stage of preconditioning ei1 10 10 initial potential 1 in SSF ei2 10 10 initial potential 2 in SSF ei3 10 10 initial potential 3 in SSF ei4 10 10 initial potential 4 in SSF ei5 10 10 initial potential 5 in SSF ei6 10 10 initial potential 6 in SSF ef1 10 10 final potential 1 in SSF ef2 10 10 final potential 2 in SSF ef3 10 10 final potential 3 in SSF ef4 10 10 final potential 4 in SSF ef5 10 10 final potential 5 in SSF ef6 10 10 final potential 6 in SSF v1 1e 4 10 scan rate 1 in SSF v2 1e 4 10 scan rate 2 in SSF v3 1e 4 10 scan rate 3 in SSF v4 1e 4 10 scan rate 4 in SSF v5 1e 4 10 scan rate 5 in SSF v6 1e 4 10 scan rate 6 in SSF es1 10 10 step potential 1 in SSF and STEP es2 10
51. macro and issue a warning message Macro Command Editor Type in commands in the editor box Each command occupies one line The command is case insensitive Space will be ignored If a parameter is required following the command a colon or a equal sign is used to separate the command and parameter The following are the legal commands Chapter 5 Control Menu command tech run save for next delay purge stir cellon celloff rdeon rdeoff qcmon qcmoff mch mchn sens sens2 autosens qt ht pw amp sw st prod freq iratio bepe bept rpm i ic parameter string string 1 999 1 32000 1 32000 1 32000 10 10 10 10 10 10 10 10 10 10 1e 6 2e4 01 05 p or n 1 10000 001 064 1e 12 1 1e 12 1 0 100000 0 100000 1e 4 1e3 001 5 1e 4 50 001 5e5 01 50 1 100000 0 100 10 10 O 100000 explanation select an electrochemical technique run experiment save data to a disk file In case of For Next loop the filename will be truncated to 5 letters The loop number 1 999 will be added to the filename for next loop only one layer is allowed for next loop delay between commands purge for a given time stir for a given time cell on between runs cell off between runs turn on RDE turn off RDE turn on QCM turn off QCM select multiplexer channel multiplexer channel selection according to the For
52. matches the port in use If the hardware test results appear on the screen the communication is working You may watch the hardware test results and see if everything is okay If you want to see if the system will run experiment properly you can use a 100K ohm resistor as a dummy cell Short the reference white and counter red electrode leads and connect the 100K ohm resistor between the red white clips and working green electrode clip Select the potential range between 0 2V to 0 2V through the Parameters command under Setup menu Run the experiment through the Run command under the Control menu You should see a straight line with large slope during the run To test the software performance you can open a data file through the Open command under the File menu There are test data that come with the software These are the actual test results of this particular instrument To open the file select the file and click OK button or you may double click the filename After you read the data you can display or process the data Try all the commands under the Graphics and DataProc menus If you don t feel comfortable about the changed data you can reload the data through the Open command again 2 5 Chapter 2 Getting Started QCM Drift Problem The long term drift is mainly due to temperature effect Long term drift should not be a problem for EQCM study since most EQCM are in seconds or minutes time scale If you need to do mon
53. message will appear This command presents a Repetitive Runs dialog box Repetitive Run 1 xj a A A E fi Time Interval Between Runs sec fo Cancel Prompt Before Each Run Hel nep None Manual Extemal Trigger Base Filename mc chiktest smpl Browse T Data Averaging When Done The following options allow you to define parameters for repetitive runs Number of Runs Enter the number of runs The parameter range is 1 9999 Time Interval Between Runs This parameter allows a delay time between two successive runs The parameter range is 0 32767 This parameter is not effective if Prompt Before Each Run is enabled Prompt Before Each Run When Manual is selected a prompt will be issued before each run except the 1st run The instrument will wait until you respond When External Trigger is selected the instrument will wait for external trigger signal External trigger is an active low signal and can be applied to the Pin 13 of the Cell Control port on the rear panel When Manual or External Trigger is selected Time Interval Between Runs has no effect Base Filename Enter the base filename Maximum 5 characters are allowed After run the data is saved The run number will be attached to the base filename i e filenameN where N is the run number from 1 to 999 If the base filename is not specified a warning will be given If you continue the system will run experiments without saving the data
54. or semi derivative treatments to the currently active data Semi derivative and semi integral are useful You can convert a diffusive peak to a Gaussian peak by using semi derivative This gives a better resolution and makes measurements easier You can also convert a diffusive peak to a sygmoidal wave This gives a time independent steady state current plateau In polarographic theory the current potential semilog analysis can be used to interpret the data This command presents a Convolution dialog box OK Cancel C Semi Integral Help ddi M Override Present Data To perform semi integral or semi derivative treatments click the OK button The following options allow you to select the order and parameters for convolution Order Selection Select either semi integral or semi derivative Override Present Data When this box is checked the currently active data will be replaced by the convoluted data Otherwise the convoluted data will be displayed but will not override the currently active data In this case when the Present Data Plot command under the Graphics menu is invoked the original data reappears This command has a toolbar button Ei 7 5 Chapter 7 Data Processing Menu Interpolation Command Use this command to insert more data points to the currently active data This command presents an Interpolation dialog box Interpolation xi Data Insertion OK IV Override Present Data C
55. powder 2 glass plates for polishing pads 5 pieces of 73 mm diameter 1200 grit Carbimet disks grey in color 5 pieces of 73 mm diameter Mastertex polishing pads white in color and 10 pieces of 73 mm diameter Microcloth polishing pads brown in color 3 Picoamp Booster and Faraday Cage allows the current measurement down to 1 pA It is fully automatic and compatible with Model 6xxC and 7xxC series instruments However it only works for the primary channel of the 7xxC series 4 Made of stainless steel and Teflon see figure below Not remote controllable Four glass cells are included 5 Not a replacement part for the CHI220 Cell Stand nw A 21
56. resistor of i E converter is determined and the combination of RC can not make up the cutoff frequency you selected This could happen if you want to select a relatively low cutoff frequency but use a low sensitivity scale or if you want to select a relatively high cutoff frequency but use a Chapter 5 Control Menu high sensitivity scale You may be able to set to the proper cutoff frequency by altering the sensitivity scale Signal Filter This box displays the actual signal filter setting Selection Select the signal filter cutoff frequency This is a 2nd order Bessel filter The setting of this filter depends on the type of experiment and the time scale of the experiment Choosing automatic will give you the default setting Line frequency notch Filter Select the line frequency notch filter will help to reduce interference from line frequency However it may also cause signal distortion You need to try and compare the data obtained with and without using notch filter and make sure it will not distort the data Normally line frequency notch filter is used when the data sampling rate is low This box displays the actual signal filter setting This command has a toolbar button ee Chapter 5 Control Menu Cell Command Use this command to control purge stir and electrochemical cleaning You can also set signal level of stir line mercury drop collection prerun drops and stabilizing capacitor This command presents a Cell
57. run Scan complete cycles Simultaneously external signal recording when the scan rate is less than 0 25V s Chapter 4 Setup Menu High Resolution ADC Check or Uncheck Use high resolution ADC when scan rate is less than 0 5 V s QCM On if Scan Rate Check or Uncheck EQCM enable lt 0 25V s Notes 1 High E and Low E should be at least 0 01 V apart 2 If unreasonable High E and Low E are entered the system will automatically readjust them 3 Depending on the Init E High E and Low E value the system will automatically readjust initial scan direction 4 The maximum potential scan range is 13 1V 5 The potential increment is 0 1 mV if the scan rate is below 100 V s The potential increment is mV at the scan rate of 1000 V s and 2 mV at 2000 V s 6 The sample interval can be 1 mV When the scan rate is below 200 V s The sample interval is 2 mV at the scan rate of 400 V s and 10 mV at 2000 V s If the scan rate is high the data sampling interval will be automatically increased 7 When large number of sweep segments are involved the data sampling interval will be automatically increased up to 0 02V If the scan rate is higher than 0 5V s the number of sweep segments will be limited by the memory size 64000 points If the scan rate is below 0 5V s the maximum data length set by the System command will take effect When the scan rate is low the specified sweep segments will be executed but only limited number of segmen
58. the sample interval this step will be ignored 3 Sample interval will be automatically increased if step time cycles sample interval exceeds 64K if data is transferred after experiment 4 Ifthe sample interval is larger than 0 002 sec data is transferred and displayed real time 5 The potential differences of Init E Final E and Step E should be less than 13 1 V 4 38 Chapter 4 Setup Menu Parameters for Chronopotentiometry In Chronopotentiometry CP two current levels can be controlled to pass the working electrode The switch of current polarity can be controlled by time or by potential The potential is recorded as the function of time The following diagram shows the current waveform applied as the function of time Anodic Current Anodic Time lt Cathodic Time Cathodic Time gt Current A Cathodic Current Cathodic Current Segment 1 Segment 2 Segment 3 Time s The following are the experimental parameters their range and descriptions Parameters Range Description Cathodic Current A 0 0 25 Controlled cathodic current Anodic Current A 0 0 25 Controlled anodic current High E Limit V 10 10 High potential limit value Low E Limit V 10 10 Low potential limit value Cathodic Time sec 0 005 100000 Cathodic run time Anodic Time sec 0 005 100000 Anodic run time Initial Polarity Cathodic or Anodic Polarity for the first segment Data Storage Intvl sec 0 0001
59. this command to print data The printer output is identical to what is displayed on the screen Use the Graph Option command under the Graph menu to customize the print output The paper must oriented as landscape If a warning pops up use the Print Setup command to set the paper orientation properly This setting will however will not be saved once you quit the program In order to set the paper orientation to landscape permanently you need to run the Printer Manager in the Main window and execute the Printer Setup command This command has a toolbar button Chapter 3 File Menu Print Multiple Files Command Use this command to print multiple data files The printer output is identical to what is displayed on the screen Use the Graph Option command under the Graphics menu to customize the print output This command presents a Multiple File Print dialog box Multiple File Print PJ ocer1 PSAQ The following options allow you to specify the name and location of the binary data files you re about to print File Name Type or select the filename s you want to print This box lists files with the extension you select in the List Files of Type box To select multiple files point the mouse cursor to the filename s you want to select and click the left mouse button while holding the Ctrl key You don t have to type the extension the system will automatically attach a bin extension to the filename Other extensions
60. uses his her own electrodes it is recommended that experimental data is compared against know standards from time to time 3 The cover of the unit should only be removed by competent personnel on direction of CH Instruments Inc 4 Reference should always be made to the health and safety data supplied with any chemicals used Generally accepted laboratory procedures for the safe handling of chemicals should always be employed 5 Evidence of any fault condition should immediately be reported to CH Instruments Inc or the local distributor Whichever is applicable Faults with the hardware are usually diagnosed through the instruments own self test procedure 6 As the instrument operates by a data coupling to a PC we recommend that sufficient space at least 2 m of linear bench is set aside in order to avoid cluttering the work area and to make easy access of the cell possible There should be some free space around the vents and fan exhaust of the instrument for effective cooling 7 Connection of the cell by the crocodile clip connections should be made in such a way A 7 Appendix as to avoid shorting of the contacts Section 2 Power configuration On unpacking the instrument the presence of the following should be noted l Mains cable 2 Cell Lead 3 Instrument instruction manual 4 optional accessories if ordered The unit is designed to operate at 110V or 220 V 20 AC power 50 60 Hz Please check the rear panel lab
61. wZ Z Zw cot phase w logZ torE phase t or E Z torE Z torE Z torE Z amp Z torE log Z amp Z t or E log Y torE Y torE Y torE Y torE Y amp Y torE log Y amp Y torE Rs E Cs E Rp E Cp E 1 CsxCs E Mott Schottky 1 CpxCp E Mott Schottky potential time dE dt time dt dE potential Potential charge 6 3 Chapter 6 Graphics Menu To select the data display format the Graph Option command should be invoked When the data is saved to the disk the display format is also saved When the data is retrieved it will be displayed just like before it is saved This is also true for Overlay Plots Parallel Plots and Print Multiple Files The Graph Option Color and Legend and Font commands allow you customize your data plot This command is disabled if there is no currently active data This command has a toolbar button 6 4 Chapter 6 Graphics Menu Overlay Plots Command Use this command to plot multiple sets of data in a single plot This is particularly useful for data comparison The color and legend will be displayed together with the corresponding filenames You can select the data files you want to plot along with the currently active data Multiple files can be selected To select multiple files point the mouse cursor to the filename you want to select and click the left mouse button one at a time while holding the Ctrl key This command will
62. E1 v5 IMPE2 cv500 IMPE3 OCPT1 DPVO IMPE4 PSAQ 2 Filename SHACVO BIN CCO BIN CV5 BIN LSVO B Files of type Data Files bin Cancel 7 Each plot will be automatically scaled according to each data set read from the disk unless the scale is frozen In the latter case all the plots will have the same frozen scale To freeze the scale use the Graph Option command The Graph Option Color and Legend and Font commands allow you customize your data plot This command is disabled if there is no currently active data 6 7 Chapter 6 Graphics Menu Add Data to Parallel Command This command is complementary to the Parallel Plots command It allows you to add more data to the parallel plots without reselecting all the files It also allows you to parallel plot data from different directories or floppy disks and control the sequence of the data in the plot Multiple files can be selected To select multiple files point the mouse cursor to the filename you want to select and click the left mouse button one at a time while holding the Ctrl key This command presents an Add Data to Parallel Plot dialog box Add Data to Parallel Plots 2 xi IMP1 J cv4 IMPE1 LSVO SHACVO Pe cvs IMPE2 EJ ssri E3 cvso0 IMPE3 EJ ocpTt EJ swo DPVO IMPE4 PSAO TAFEL1 SSS gt Filename NPVO BIN IMPO BIN Files of type Data Files bin x Cancel A The plot will be scaled according to the currently act
63. Ground 6 Ground 7 Ground 8 Ground 9 Ground The external Potential Input is disabled Please contact CHI to enable it if you really need to use external voltage input i The input voltage range is 10 V If the external signal is greater than 15 V permanent damage could occur For signals with high voltages a resistor divider should be used For signal with small voltage range lt 0 1V a preamplifier may be needed in order to record the signal properly The input impedance of the input stage is 1 M ohm Appendix Instructions of Software Update Instrument control software has two portions One is the software on the PC side There is also software inside the instrument Sometimes software update will only involve the software on the PC side but occasionally software inside the instrument is also involved The software inside the instrument is stored in the flash memory You can get updated software on both PC side and instrument side from CH Instruments The software installation on the PC side us described in Chapter 2 The software on the instrument side is a hexadecimal file CHI4xxA HEX where 4xxA is the model number In order to update the software inside the instrument use the Update Instrument Program command under the File menu to bring up the following dialog box Update Flash Memory in the Instrument y x Filename Jc chi chi440a hex T OK Update Help You can type in the hexadecimal file name an
64. Menu Present Data Plot Command Use this command to plot the currently active data Use this command to zoom out the plot You can rescale the X and Y axis by moving the mouse cursor to the axis and see the cursor change to lt gt X axis or Y axis You can then hold down the left mouse button and drag the mouse When you release the mouse button the axis will be rescaled It provides a convenient way to zoom out further than the default scale It can be particularly useful when plots are overlaid if some of the files have a higher range than the default range If you double click the axis an Axis Options dialog will be brought up Axis Options m Grid and Inv Cancel Invert Electrode Area fi V Grid Current Density m Axis Label Expression Help Scientific I E vs Reference Electrode Engineering Ref Electrode Ag AgCl Long Auto Short Auto Freeze fo To 3 6e 006 Tl Title Unt Grid W chanoe Pont Color Thickness X Y Axis CJ Change hoo x Y axis Title Rotation on Printer 270 degree v Axis Label Regular M E Chane Arial Narrow Axis Title Times New Roman Bold fis Change You can change the axis settings Please see also Graph Options Color and Font descriptions The unique selections here are Axis Label Expression Long Divisions and Short Ticks If you choose Scientific Expression the axis label is in floating format For instance one m
65. Next loop initial potential high limit of potential in CV CA CP low limit of potential in CV CA CP final potential for single sweep tech and PSA use open circuit potential as init E This flag will be turned off after a new init E is entered potential for the second working electrode turn on the second working electrode turn off the second working electrode scan rate increment potential initial potential change direction in CV CA initial current polarity in CP number of segments in CV and CP sample interval or data storage interval in BE CP sensitivity sensitivity for the second working electrode automatic sensitivity for slow CV or LSV quiescent time before run hold time at final E in TAFEL pulse width a c or pulse amplitude sampling width total sample time in l t curve sampling period frequency end current ratio in BE pre electrolysis potential in BE pre electrolysis time in BE rotation rate of RDE controlled current in PSA cathodic current in CP Chapter 5 Control Menu ia 0 0 25 anodic current in CP tc 0 05 100000 cathodic time in CP ta 0 05 100000 anodic time in CP priot time priority in CP prioe potential priority in CP fl 0001 10000 low frequency in IMP fh 001 100000 high frequency in IMP mt 1 1024 measuring time when freq is above 10Hz in IMP cl1 1 4096 measuring cycles when freq is 1 10 Hz in IMP cl2 1 4096 measuring cycles when freq is 1 1 Hz in IMP cl3 1 256 measuring cycles when
66. PT1 IMPE4 PSAQ E File name evo Files of type Data Files bin Cancel Wi The following options allow you to specify the file to select File Name Type or select the filename You don t have to type the extension The system will automatically attach an extension to the filename List Files of Type Select the type of file Only bin binary data file is available Drives Select the drive in which the system stores the file Directories Select the directory in which the system stores the file Chapter 7 Data Processing Menu Signal Averaging Command Use this command to perform signal averaging to the currently active data and the disk data file s The currently active data will always participate Several sets of data are added together and then divided by the number of data sets If any set of data has different X array from the currently active data an error message will be issued and this set of data will be ignored This command presents a Signal Averaging dialog box so you can select the data file s for signal averaging Signal Averaging IMPE1 J IMPE2 NFO IMPE3 OCFPT1 IMPE4 PSAO 2 Files of type Data Files bin x Cancel Wi The following options allow you to specify the file to select File Name Type or select the filename You don t have to type the extension The system will automatically attach an extension to the filename To select multiple files point the mouse
67. Potential Axis e c Com 3 Positive Left C Com 6 aoe C Com Positive Right C Com C Com Current Axis C Com 10 eel C Com11 ositive Up C Com12 C Positive Down m Line Frequency Current Polarity Erase ADC Calibration Coefficients 60Hz C Cathodic Positive 50Hz Anodic Positive Data Lenath 128K J Save retrieve data during run Windows J Present Data Override Warming English C Oriental l Save Text File As Well The following options allow you to set up your system Communication Port Select the communication port to link the PC to the instrument Current Polarity You can either select cathodic current as positive current or anodic current as positive current You should set this before experiment otherwise the experimental results peaks and waves will not be reported properly Potential Axis You can set positive potential axis either left or right This is meaningful only for voltammetric or polarographic modes Current Axis You can set positive current axis either up or down 4 48 Chapter 4 Setup Menu Line Frequency Set line frequency according to what is applied This helps set default sample interval in certain techniques to reduce the interference from the line frequency Windows if you are using English Windows please choose English If you are using Chinese Japanese or Korean Windows check Oriental Oriental Windows shows slightly bigger letters than Englis
68. Pulse Amperometry In Differential Pulse Amperometry DPA a clean potential could be applied for electrode conditioning with no current sampling Two potential pulses are applied after the cleaning step and the current at the end of each pulses are recorded as the function of time During the experiment only the difference of two current samples is displayed After experiment the current responses to the two potential pulses are also available for display The following diagram shows the potential waveform applied as the function of time and the current sampling scheme Data Sampling as Z Clean E R I E El L Init E E2 Clean T T1 T2 Cycle 1 Cycle 2 Time s The following are the experimental parameters their range and descriptions Param Range Description Init E V 10 10 Initial potential during quiescent time Cleaning E V 10 10 Electrode cleaning potential Cleaning Time sec 0 32 Electrode cleaning time Pulse E1 V 10 10 First pulse potential Pulse T1 sec 01 32 First pulse time Pulse E2 V 10 10 Second pulse potential Pulse T2 sec 1 32 Second pulse time Number of Cycles 10 100000 Number of Repetitive Cycles Quiet Time sec 0 100000 Quiescent time before taking data Scales During Run 1 2 3 Number of current display scales Sensitivity A V le 12 0 1 Sensitivity scale Open Circuit During Check or Cleaning step could be either held at a Cleaning Uncheck c
69. R Comp Test Results o Resistance ohm all cancel RC Constant usec i Comp Level Help Uncomp RA ohm A dd JV iR Compensation for Next Run iR Comp Test iR Comp Enable TEREM meea Eo Once Always Step Amplitude V 005 eae Comp Level ho Automatic Manual Overshoot 2 r Manual Compensation Test Resistance ohm jo The following options allow you to set iR compensation parameters iR Comp Test Results If you click the iR Test button the system will engage solution resistance and cell time constant test The result will be reported here After that the system will test the stability by gradually increase the compensation level until the desired compensation level is reached or if the system is no longer stable The actually allowed compensation level and the uncompensated resistance will be displayed The uncompensated resistance is calculated from the measured resistance and the allowed compensation level Please note that the maximum allowed resistance compensation may also be limited to the feedback resistor of the i E converter iR Comp Test Before start iR compensation test you should check the test parameters Test E is the test potential where no electrochemical reaction will occur When the system is doing test it applies a potential step around the test potential The test result is good
70. Sampling Rate 1 M Hz at 16 bit resolution Scan rate V s 0 000001 to 20000 Pulse width sec 0001 1000 Pulse width sec 0 001 to 10 Sampling width sec 0 0001 to 10 Frequency Hz 1 to 100000 Frequency Hz 1 to 10000 Frequency Hz 1 to 5000 Frequency Hz 0 0001 to 100000 Appendix Techniques for the Model 700C Series Bipotentiostat eS GV SiS ir Se SO tO Pp SVE o E A ee E er a ee ae ee ee eee ee Corresponding polarographic mode can be performed amp Corresponding stripping mode can be performed Phase selective data are available Dynamic Range of Some Experimental Parameters for Model 700C Series Parameters Range Techniques Involved Potential V 10 to 10 Current A 0 to 0 25 one channel only Current A 0 to 0 125 dual channel Sensitivity A V 1x10 to 0 1 both channel Sampling Rate 1 M Hz at 16 bit resolution Scan rate V s 0 000001 to 20000 CV LSV Pulse width sec 0001 1000 CA CA Pulse width sec 0 001 to 10 DPV NPV Sampling width sec 0 0001 to 10 DPV NPV Frequency Hz 1 to 100000 SWV Frequency Hz 1 to 10000 ACV Frequency Hz 1 to 5000 SHACV Frequency Hz 0 0001 to 100000 IMP Dual channel measurements apply to CV LSV SCV CA DPV NPV DNPV SWV and i t Appendix Techniques for the Model 800B Series Electrochemical Detector Techniques 800B 802B 810B 812B 820B 822B 830B 832B 840B 842B Corresponding polarographic mode can
71. Start E V 10 10 Duration s 0 100000 Step E1 V 10 10 Step Time 1 s 0001 100000 Step E2 V 10 10 Step Time 2 s 0001 100000 Step Segments 1 2000000000 Galvanostatic Mode Check or Uncheck Notes Description Starting potential Duration at Start E First step potential Duration of each step Second step potential Duration of each step Step segments each segments is half cycle Galvanostatic mode on or off 1 The potential range among Start E Step E1 and Step E2 should be less than 13 1 V 2 Ifthe Duration at Start E is less than 0 001 sec the Start E will be ignored 3 The step is in a sequence of Step El Step E2 Step El Step E2 The ending potential is at Step E1 for odd number of segments at Step E2 for even number of segments Chapter 5 Control Menu 4 If Galvanostatic Mode is checked the Step E1 il and Step E2 i2 will be in current unit Run Press the Run button will activate the step function generator A status box will be displayed showing the number of steps completed the remaining steps and the remaining time You can cancel this function by pressing the Stop pushbutton No data will be collected and displayed Chapter 5 Control Menu Preconditioning Command Use this command to condition working electrode before running an experiment This can be useful for cleaning the electrode or other usages Preconditioning occurs before the deposition or quiet time This
72. Table of Contents Chapter 1 General Information Introd ction s 7 S cis area nea raa in er a eaaa oae AE Tar narar SEak Electrochemical Techniques s sseensesessseesessseesseseessessessessressessessresseesessressseseess Software Peatuhes tise erat n e ea a e fae a ee e a a System Requirements sssssessesseeseesseeseessetsresresstesresttsstessesrtssessesressessesstssresseese Hardware Sp cifications ajc danino a Ae Se aoe Chapter 2 Getting Started J stallatioi 4 11 Gssncouaseasntstachscioetensugvinsd tnpextesavedachdatganeddaentcashanusvasveacsialauteaeieteas R nming OC ask seats secant a e a Gateana pes a a a a ae a Testing oianean a A a A E OC Mri PROD ICM arrete en r a A E A eases Some WSS hal TPs ecreis a uae eared E E E EEE ER a i Installing USB Driver Under Windows ccceceeeene eee eee ena eenens Chapter 3 File Menu Openi Command ccicac esas atm acces hs sachet E a AEA SaveAss Command 0 09 cac oso cotta aa io oeahi nso ion acetate aai D lete Command adaa a Sea cc a sat ats casted dig Ae a Shad Sea scales aa Retrieve Command yt esate ool tok Loe nce E E tat ls ment cca hed a List Data File Ora A eck Fonscns ricenca aa A i ems r n nena Co vertto Text Command Sisde n aa a a ie e adai Texte Porat Command aaeeea raa cist aa aA A E todd EATE A ATARATE ERANA Import Text File Command asco cc ash cau cecnog sacasieaaa feared wenn ageeees eee Prat ronan atenas EESE EEEE EAE usenet Print Multiple Files Comm
73. USA Tel 512 402 0176 Fax 512 402 0186 E mail info chinstruments com Web Page http www chinstruments com Chapter 2 Getting Started Installation Software The instrument will be controlled by an IBM PC with Windows 95 98 NT Me 2000 XP operating system A free serial port or a USB port is required for communication between the instrument and the computer Refer to your Windows User Manual to be familiar with Windows operation To install the software insert the software CD ROM You can run SET EXE on the CD ROM directly to extract the files and the files will be automatically copied to the hard drive The default directory is C CHI It is very important to use it for the program and configuration files The C CHI directory is used for the automatically generated configuration file cfg When the program starts it will always look for the existing configuration file in C CHI directory When the program ends it will save the configuration file to the C CHI directory If the program can not find C CHI directory the configuration files will be spread everywhere Next time the program starts it will not be able to use the configuration file for customized setting by the user Once the files have been copied you can use Windows Explorer or File Manager to find the executable file CHI EXE in the C CHI subdirectory or folder Double click the filename to start the program The installation just copies al
74. USB port in our office they all seem to work but when it is not working besides the installation instructions we really do not know how to further diagnose and support it since the software is not provided by us we have no control on it If you still want to go for it please set the USB Serial selection switch inside the instrument please see Figure 2 1 and following the following instructions to install the USB driver software 1 Find the CP2101 USB driver software on the software CD ROM 2 Double click the file CP2101 EXE the following dialog box will appear WinZip Self Extractor CP2101_EXE x To unzip all files in CP2101 EXE to the specified folder press the Unzip button Unzip To Folder Run WinZip x Close M Overwrite Files Without Prompting About Wd Help Nico Mak Computing Inc Www Wwinzip com Click Unzip button to unzip the files to c CP2101 by default or other folder 3 Go to c CP2101 or other folder you will find a SETUP EXE file Double click this filename a following dialog box will occur Install Driver i xi Ready to install CP2107 USB to UART Bridge Controller driver C Program Files Cygnal CP2101 USB to UART Bridge Controller Browse Click Install button will start installation process Wait long enough time until the installation is completed 2 8 Chapter 2 Getting Started 4 Connect USB cable type A B from your computer
75. X c fitting and so on You need to adjust the fitting algorithm and polynomial orders for best fitting results You may also need to adjust the potential of the peak foot Save to Override Original Data When the OK button is clicked if No Action is selected the graphical screen will show the original data and the fitted baseline The original data remains unchanged If Difference is selected the original data will be replaced by the difference data The difference data is obtained by subtracting the baseline data from the original data If Baseline is selected the fitted baseline data will be saved View Baseline This button will allow the user to view the original data and the fitted baseline together to evaluate the fitting results This is important because you need to be sure that the fitting is ideal and correct If the peak defining lines affect your vision you can turn off the Screen Baseline option by using the Graph Options command under the Graphics menu The original data remains unchanged When the Present Data Plot command under Graphics menu is invoked the original data reappears View Difference This button will allow the user to view the difference data by subtracting the fitted baseline from the original data This is helpful when evaluating the fitting results The original data remains unchanged When the Present Data Plot command under the Graphics menu is invoked the original data reappears
76. ach channel Data acquisition 16 bit 5 kHz maximum Chassis dimension 12 5 W x I I D x 4 75 H Appendix Model 1100A Series Power Potentiostat Galvanostat The Model 1100A series power potentiostat galvanostat is designed for electrochemical applications that require relatively large current and high compliance voltage such as battery corrosion electrolysis and electroplating The current range is 2 A The compliance voltage is 25 V Instrument contains a digital function generator a data acquisition system filters for the current signals iR compensation circuitry a potentiostat and a galvanostat Model 1140A The potential control range is 10 V Similar features can also be obtained by using the combination of the CHI600B series and the CHI680 Amp Booster However the CHI1100A series is more compact and lower cost This series is capable of measuring current down to tens of picoamperes The instrument is reasonably fast For instance the scan rate in cyclic voltammetry can be up to 2000 V s Specifications Potentiostat CV and LSV scan rate 0 000001 to 2000 V s Galvanostat Model 1140A Potential increment during scan 0 1 mV if below 100V s Potential range 10 to 10 V CA and CC pulse width 0 001 to 1000 s Potentiostat rise time lt 2 us CA and CC Steps 320 Compliance voltage 25 V DPV and NPV pulse width 0 001 to 10s SWV frequency 1 to 100 kHz Automatic potential and current zeroing Signal low pass
77. allow you select multiple files in the same directory In order to overlay data in the different directory or disks use the Add Data to Overlay command This command presents an Overlay Data Display dialog box Overlay Data Display Look in SY chi6 ex Eee IMPE1 IMPE2 IMPE3 OCPT1 IMPE4 PSA0 gt Filename PLSVO BIN CV1 BIN CV3 BIN CVO BIN Files of type Data Files bin Cancel 4 The plot will be scaled according to the currently active data This command does not check the type of data If both X and Y values fall into the plot scale the data point will be plotted The Graph Option Color and Legend and Font commands allow you customize your data plot The color and legend of each traces can be specified by Color and Legend command This command is disabled if there is no currently active data Chapter 6 Graphics Menu Add Data to Overlay Command This command is complementary to the Overlay Plots command It allows you to add more data to the overlay plots without reselecting all the files It also allows you to overlay data from different directories or from floppy disks Multiple files can be selected To select multiple files point the mouse cursor at the filename you want to select and click the left mouse button one at a time while holding the Ctrl key This command presents an Add Data to Overlay dialog box Add Data to Overlay BE Look in a chi6
78. ampling width Pulse Period sec 0 01 50 Potential pulse period or dropping time Quiet Time sec 0 100000 Quiescent time before potential scan Sensitivity A V le 12 0 1 Sensitivity scale Notes 1 Init E and Final E should be at least 0 01 V apart 2 Pulse Width should be no more than half of Pulse Period otherwise the system will automatically readjust Pulse Width 3 Sampling Width should be no more than half of Pulse Width otherwise the system will automatically readjust Sampling Width 4 When amplitude is negative the pulse direction is different from the potential scan direction 4 15 Chapter 4 Setup Menu Parameters for Normal Pulse Voltammetry In Normal Pulse Voltammetry NPV the base potential is held at Init E A sequence of potential pulse with increasing amplitude is applied The current at the end of the potential pulse is sampled This current is recoded as the function of the pulsed potential The following diagram shows the potential waveform applied as the function of time and the current sampling scheme oN gt or p L Incr E A x Init E Pulse Period 4 k Pulse Width Final E Aik A k Sample Width Time s The following are the experimental parameters their range and descriptions Parameters Range Init E V 10 10 Final E V 10 10 Incr E V 0 001 0 05 Pulse Width sec 0 001 10 Sampling Width sec le 4 10 Pulse Period
79. an change the impedance simulation parameters such as frequency range and number of data points per decade of frequency Please notice that the equivalent circuit you draw can be used for both simulation and fitting To perform a simulation click the Sim button After that the program will Chapter 9 Simulation Menu exit the equivalent circuit edit field and display the simulated data on the screen Be aware that unsaved data will be erased when a new simulation starts Save your existing data before starting a simulation To start fitting you need to have a set of impedance data first The impedance data can be obtained by running impedance measurements or by a simulation You also need to draw the circuit that would match the equivalent circuit of your actual system If the equivalent circuit does not match the mechanism of the actual data the data may not fit very well You may need to revise your circuit The fitting program may not be perfect Sometimes it does not fit very well even with a known simulated data set You may also find that fitting results be affected are dependent on the initial value of the components If you experience problems please e mail us the data We will try to study it and improve it but cannot guarantee better results Efficient fitting algorithms are difficult and complicated to obtain Press the Fit button on the toolbar to start the fitting process During fitting the elapsed time fitting error and
80. ancel lt To perform interpolation click the OK button The following options allow you to select the parameters for interpolation Data Insertion Density The larger the number the higher the final data density will be When the number of data points exceeds the allowed memory size a warning will be given and the command is terminated The data insertion density can only be a power of 2 Fourier transform is used in this case Override Present Data When this box is checked the currently active data will be replaced by the interpolated data Otherwise the interpolated data will be displayed but will not override the currently active data In this case when the Present Data Plot command under the Graphics menu is invoked the original data reappears 7 6 Chapter 7 Data Processing Menu Baseline Fitting amp Subtraction Command Use this command to fit the baseline and subtract the fitting curve from the currently active data This is very useful for peak evaluation In order to perform Baseline Fitting and Subtraction you need to specify the potential on the two sides of the peak base You also need to specify the algorithm and orders of fitting Baseline Fitting and Subtraction only works for certain peaks it does not work for all the techniques This command presents a Baseline Fitting amp Subtraction dialog box Baseline Fitting amp Subtraction Two Sides of Peak Foot aE sah i o Cancel From fo To fo
81. and ssssesesseseesessesessessessessesseseesesserresseseesesseseesessesees Print S tup Command siioni i ee e E E ERRE E R e Exit Command exis eattiestNGe r E A TE E T een ees Chapter 4 Setup Menu Techniig e Command noosncsiiiniencue hiii e a a ae Parameters Cominandiso ensino erin Os Sh aa ta ets Raa Parameters for Cyclic Voltammetry i5 sasces cessadcdsaaccuae eaten qascedsvaestece steers Parameters for Linear Sweep Voltammetry ccceccecsceesseesteceeeeeeeeeeees Parameters for Staircase Voltammetry 0 ccccccescceeeceeseeeeseeetene eee eens Parameters for Tafel Plot s sssccessssich cvs tewieveeene dea diag cesiaeng aiaia Parameters for Chronoamperometry ccccsccesceseeceeeeeeeeeeeeceeceeeeenseees Parameters for Chronocoulometry ccccccesscesseeeseeeseeceeceseeeeseeneeeaeeees Parameters for Differential Pulse Voltammettry ecceesceeeseeereeeeees Parameters for Normal Pulse Voltammettry cccsccescceeseceeseeetseeeseeees Parameters for Differential Normal Pulse Voltammetry ceeeee Parameters for Square Wave Voltammetry ceceesceeceseeneeeeeeeeeseenaes Parameters for A C Voltammetry cc sccssecssianesiasiwcnsiiansenranceon Parameters for 2nd Harmonic A C Voltammetty cccceesseeeteeeeeeeeees 4 22 Parameters for Amperometric i t Curve oo eceececcceesteeetseceseceteceeeeeeseeesaeenes 4 24 Parameters for Differential Pulse Amperometty
82. arameters and some other variables You can store all the parameters needed for simulation on a disk or read them from a disk You can also check the equilibrium concentration 9 1 Chapter 9 Simulation Menu Mechanism Edit This edit box allows you to edit the reaction mechanism You may check the Mechanism Select box to see if the mechanisms you want to study are predefined If so click the mechanism in the Mechanism Select box the mechanism will appear in this edit box Only certain high end models will work with edited reaction mechanism even if the user specified mechanism is identical to the predefined one Whenever you try to type into this edit box the Mechanism Select box changes the selection to User Input For user input use only one letter A Z to represent each chemical species The letter e is dedicated to electron transfer process Upper case and low case letters are interchangeable Spaces will be ignored The software can simulate any reasonable combination of electron transfer 1st and 2nd order chemical reactions A maximum of 11 steps and 9 chemical species will be accepted The following are legal format At e B reduction A e B oxidation A B chemical reaction A B C chemical reaction A B C chemical reaction A B C D chemical reaction If you don t follow the convention an error message will appear before you take any other action Mechanism Select There are 10 predefined reaction mechanis
83. ase filename an override warning will be issued The experimental conditions should be set before this command is executed Multiplexer related Macro Command There are also two Macro command for multiplexer One is mch This macro comamnd allow you to set individual channel The other macro command is mchn This is used in For Next loop It will select the channel according to the For Next loop counter However mchn will run in 1 2 3 4 sequence You can not skip channels when you use For Next loop 5 9 Chapter 5 Control Menu Macro Command Use this command to execute a series of commands in the order you specified This is particularly useful if a sequence of action needed to be taken This command presents a Macro Command dialog box Macro Command x Macro Command Editor OK Cancel Help Read Save Run Macro ikkl The following options allow you to edit load save and execute macro command Read You can read in macro command that you saved as a disk file before This command presents a Open dialog box so you can select your file Save You can save the macro command that you edited to a disk file You can retrieve it later This command presents a Save As dialog box so you can name your file Execute Press this button will execute the macro command Before execution the system will check the validity of the command and parameters If error is detected the system will terminate the
84. at the Equilibrium Checking this box will make the system calculate and use the concentration at the equilibrium when starting a simulation The equilibrium state is calculated according to the kinetic parameters and input concentrations If this box is unchecked the simulation will use the input concentration as an initial condition Display Concentration Profile during Run Checking this box will make the system to display the concentration profile along with the voltammogram during the simulation This is very helpful to understand the reaction mechanism and very instructive when teaching to students In voltammograms the current display scale is determined by the sensitivity scale that is selected in the Parameters command If the current axis scale is too high the voltammogram may appear as a flat line If the current axis scale is too low the data point will be too scattered However the post run data display will always autoscale the voltammogram and makes it readable You may want to change the sensitivity scale for next run according to the post run display In concentration profiles relative concentrations and relative distances are used The total concentration of all the involved species is set to unity The concentrations of each species during simulation are referred to this value The unity distance is set to 6 sqrt Dt where D is the diffusion coefficient and t the total time involved in the given experiment To change the scales
85. ata Segment fi Equilibrium E 0 313 Cancel m Cathodic Tafel Slope Potential Range Help jo 53 to 0 253 m Anodic Tafel Slope Potential Range gt 0 373 to 0 473 9 995e 001 Cathodic Tafel Slope Anodic Tafel Slope 5 040e 000 Linear Polarization A Corrosion Current 4 The following options allow you to enter the parameters that will be used to calculate the corrosion rate Data Segment If you have more than one segment of data you need to specify which segment of data you want to use to calculate the corrosion rate Equilibrium E The program will search for the potential value where the current is closest to zero or a minimum value and assign that corresponding potential as the equilibrium potential You can change the default value reported by the program Cathodic Tafel Slope Potential Range By default the cathodic Tafel slope potential range starts at 60 mV more negative than the equilibrium potential and has a range of 100 mV You can change this potential range Anodic Tafel Slope Potential Range By default the anodic Tafel slope potential range starts at 60 mV more positive than the equilibrium potential and extend the range for 100 mV You can change this potential range Calculate 8 9 Chapter 8 Analysis Menu Once you think the data segment equilibrium potential anodic and cathodic potential ranges are properly set you can click this button to calculate the catho
86. atio is referred to the initial current If the data storage interval is 1 second the initial current is the average current of the first second after electrolysis 4 Ifthe end current ratio is zero the electrolysis will continue forever In order to stop the experiment the Stop command should be invoked 4 32 Chapter 4 Setup Menu 5 During the experiment the data will be updated in a rate same as data storage interval 6 The data storage interval should be chosen according to the length of the experiment The longer the experiment the larger the data storage interval Long data storage interval will have better signal averaging and less noise However for a thin layer cell short data storage time should be used in order to observe the detail of the electrolysis process 7 During electrolysis whenever the data exceed the maximum allowed points the data storage interval will be doubled automatically Therefore data points will not overflow for an unexpected long electrolysis 4 33 Chapter 4 Setup Menu Parameters for Hydrodynamic Modulation Voltammetry In Hydrodynamic Modulation Voltammetry HMV potential is increment from Init E toward Final E The following diagram shows the potential waveform applied as the function of time At each potential the rotating speed of the RDE is modulated The resulting alternating current is sampled and analyzed using a software lock in amplifier During the experiment only the abs
87. ation smoothing purge stir and prerun mercury drops enable or disable automatic smoothing after running each experiment This command presents a Run Status dialog box i IV Rotate During DepositionTime I Check Connection Before Run I Rotate During Quiet Time Cal J Use Open Circuit E as Init E I Rotate During Run Hel J External Trigger Run Rotate Between Run __Hep JV iR Comp for Next Run Rotation Speed rpm jo Bun Smooth After Run SMDE Drops Before Run fi V Purge Between Runs IV Stir Between Runs V 2 Off During Quiet Time if applicable Abort Experiment at Level Abort Quiet Time Current Display during Quiet Time No Current Overflow No No C Curent 4 gt 2 c c Current A gt Numerical C Current A lt fO C cures ok Charge C gt 100000 10s Change lt 0 Graphical The following options allow you to change certain status related to running experiment Calibration before Run When this box is checked the potential and current offset will be measured and will be compensated Disable this option will reduce the time delay before running each experiments Check Connection before run When this box is checked the connection of the counter and reference electrodes will be checked If one of the electrodes is not connected a warning message will appear This can prevent accidental damage of working electrode due to open loop of the potentio
88. ation is encountered the command is terminated and an error message will appear In most cases real time data display is possible However when the data acquisition speed is higher than the data transmission rate the data will be displayed immediately after the experiment You can stop running experiment by invoking the Stop command You can copy the graphics during run to the clipboard This command has a toolbar button gt Pause Resume Command Use this command to pause and resume experiment This command does not work for time based experiments such as CA CC BE i t DPA DDPA TPA IMP IMP t CP PSA and etc This command has a toolbar button 5 1 Chapter 5 Control Menu Stop Run Command Use this command to stop running experiment You can also use this command to stop repetitive runs and macro command while running experiment This command has a toolbar button Reverse Scan Command Use this command to reverse the potential scan direction during cyclic voltammetry experiment Each time this command is invoked sweep segment counter increments If this command is used during experiments some data analysis features will not work such as peak search This command does not work for other techniques This command has a toolbar button 5 5 2 Chapter 5 Control Menu Run Status Command Use this command to check and change certain status related to running experiment such as iR compens
89. ayer capacitance and adsorption of Anson plot Q t plot is not your primary interest you may not worry about it However if the data distortion can be seen visually you have to lower the sensitivity scale Sometimes you may use i E converter filter to slow the system down but make sure that the time constant of the filter 1 cutoff freq is much shorter than the pulse width In order to reduce noise and enhance the accuracy of the measurement it is recommended to use the highest sensitivity scale possible 5 Charge is obtained by integrating the current Due to the offset of the amplifier you may observe charge drift even at a zero current The best way to correct this problem is to do background subtraction Use the Background Subtraction Command under the DataProc menu You can connect the cell in a way as you do actual experiment then disconnect the working electrode leads Run experiment Save this data as background data Now connect the working electrode leads and run experiment again Use Background Subtraction to obtain corrected data You need to run background measurements again when you change the sensitivity scale 6 Ifthe sample interval is less than 0 002s the data will not be transferred on the real time base Instead the data will be transferred after the experiment is completed Cell is turned off during the data transfer unless the Cell On between Run option is selected From start of experiment and data transfer th
90. both sides of the peak or wave This parameter is only meaningful for automatic result report For cyclic voltammetry data select the segment by the Graph Options command under the Graphics menu This command has a toolbar button Chapter 6 Graphics Menu XY Plot Command Use this command to make an X Y plot of your own data You can also do linear curve fitting to the data After you edit the data click the OK button to do the plot The X Y plot is temporary and it disappears if other data display commands are invoked However you can use Graph Option Color and Legend and Font commands to customize your plot The command presents the X Y Plot dialog box X Y Plot EI x Y Data Array Editor oO PROBE Cancel Help Read Save Overlay Plot Parallel Plot Plot 1 00 7 83 a T Linear Curve Fitting x Axis Title Potential Unit lv Y Axis Title Dropping Time Unit sec Header Electrocapillary Curve Note The following options allow you to edit data and enter plot options XY Data Array Editor Enter your own X Y data points Use comma or space as separator Each pair of data occupies one line xl yl x2 y2 x3 y3 Read Use this command to read the data you saved Save Chapter 6 Graphics Menu Use this command to save your data XY titles units header and note will be saved along with the data Overlay Plot Use this command to overlay several data plots If you want to have both sy
91. cients You can choose either the linear scale or the logarithmic scale Override Present Data When this box is checked the currently active data will be replaced by the Fourier spectrum data Otherwise the Fourier spectrum will be displayed but will not override the currently active data In this case when the Present Data Plot command under the Graphics menu is invoked the original data reappears Chapter 7 Data Processing Menu Chapter 8 Analysis Menu Calibration Curve Command Use this command to make a calibration curve The system displays the Calibration Curve dialog box Calibration Curve Xx Concentration Peak Height OK Standard 1 fi oo 2391 e 007 Ena Standard 2 1200 4 782e 007 Standard 3 200 7 023e 007 Slope 2 2788e 009 He Standard 4 400 ja 272e 007 Intercept 1 65199e 008 Read Standard 5 500 fi 1546 006 Correlation 0 999931 Save Standard 6 jo jo E 228 62 5 375e 007 _ Calculate Help Unknown x Axis Title Concentration x Axis Unit ppb i Y Axis Title Peak Current Y Axis Unit ja Header Cu in waste water Note The following options allow you to enter the data for calibration curve calculation or plotting Standard Enter the concentration and peak height current obtained from standard solutions Unknown Enter the unknown peak height if available for unknown concentration calculation X Axis Title Enter the X axis title such as Concentration
92. cursor to the filename you want to select and click the left mouse button one at a time while holding the Ctrl key List Files of Type Select the type of file Only bin binary data file is available Drives Select the drive in which the system stores the file Directories Select the directory in which the system stores the file Chapter 7 Data Processing Menu Mathematical Operation Command Use this command to perform mathematical operations to the currently active data You can work on both X and Y arrays The allowed operations include addition subtraction multiplication division exponential logarithm square square root and reciprocal This command presents a Math Operation dialog box Math Operation j xi m Operation Selection Data Selection geevcesceccesessceey gaan C X Data Array Cancel Subtraction Y Data Aray ag Multiplication Hep C Division C Exponential Add fo C Logarithm Sub fo C Square Mul hooo C Square Root Div ooo C Reciprocal V Override Present Data To perform mathematical operations click the OK button The following options allow you to choose the type of operation and the destination of the data array Operation Selection Select the operation you want to apply to the data If addition subtraction multiplication or division is chosen you have to provide the operand Data Selection You can choose either the X data array or the Y data array f
93. d in the edit box If the check box is unchecked or if the number of data points to be removed is zero no action will be taken Override Present Data When this box is checked the currently active data will be replaced by the new data after data points removal Otherwise the new data will be displayed but will not override the currently active data In this case when the Present Data Plot command under the Graphics menu is invoked the original data reappears Chapter 7 Data Processing Menu Data Point Modifying Command Use this command to visually modify the data points of the currently active data You can correct data points due to bad mercury drop or any other reason This command presents a Data Point Modifying dialog box Data Point Modifying x Segment il Cancel IV Override Present Data Help To modify data points click the OK button first The mouse cursor now changes to an upper arrow cursor When you move the mouse cursor in the data display region a hair cross cursor will appear at the data point corresponding to the X axis position of the mouse cursor Move the mouse horizontally to select the data point you want to modify When the hair cross cursor appears at the selected point press the mouse button Drag the mouse up or down in the direction you want to move the data point The hair cross cursor will move up or down correspondingly When the hair cross cursor is located at the position where you wa
94. d path in the Filename field Or you can use Browse button to select the hexadecimal filename Click Update button to upload the program to the instrument flash memory During upload please be patient and wait Please do not activate any other program It could cause the upload to fail and mess up the flash memory and instrument will not be useable One has to do force programming Please contact CH Instruments if this occurs If download failed you will get an error message You may need to turn off the instrument and wait for 5 10 seconds and turn the instrument on You may need to exit the PC program and restart the program You can then try again If the download is successful you will get a confirmation message You can now use the instrument Appendix Trouble Shooting Possible Cause link failed power is not on turn on the instrument power bad cable check and change cable comm port setting does not use System command under match the port in use Setup menu to set the port Bt SSS computer problem make sure no network card or fax modem card in the computer system If there is one unplug it and try again If the problem persists try a few more computers static discharge turn off and turn on the instrument again You may also have to reset the computer mouse action process E communication failed reset the instrument and the computer C the computer hardware test error repeat the hardware test rec
95. dic and anodic Tafel slope the linear polarization resistance in ohms and the corrosion current in amperes Chapter 9 Simulation Menu Mechanism Command A digital cyclic voltammetry CV simulator and digital impedance IMP simulator software is integrated as well as a fitting program for impedance data The following pages 9 1 to 9 10 relate to the CV simulator only For instructions for the impedance simulator and the fitting program please refer to a later portion of this chapter pages 9 11 Mechanism Command for CV simulator Use this command to set the reaction mechanism the concentration of each involved species the kinetic and experimental parameters and some other variables before your perform a simulation You can store all the parameters needed for simulation into a disk and read from it You can also check the equilibrium concentration This command presents a Digital Simulation dialog box Digitor Simulation Mechanism Edit Mechanism Select s quare Scheme Cancel Help oO ras EEE Read Save Exp Param Kinetics Square Scheme System under study Diffusive Conc J Dimensionless current Equilibrium I ir j IV Display concentration profile during run Conc Range fi Dist Range fi Time Delay Loop usec jo Variables ESR RP ER EE The following options allow you to set the reaction mechanism the concentration of each involved species the kinetic parameters the experimental p
96. displayed After experiment the phase selective second harmonic current at any phase angle are also available for display The following diagram shows the potential waveform applied as the function of time Final E Amplitude Ne Potential V Init E J k Sample Period Time s The following are the experimental parameters their range and descriptions Parameters Range Description Init E V 10 10 Initial potential Final E V 10 10 Final potential Incr E V 0 001 0 05 Increment potential of each point Amplitude V 0 001 0 5 A C amplitude Frequency Hz 0 1 5000 A C frequency Sample Period sec 1 50 Data sampling period or dropping time Quiet Time sec 0 100000 Quiescent time before potential scan Sensitivity A V le 12 0 1 Sensitivity scale Bias DC Current off range Enable dc current bias during run on Auto Sens Check or Automatic sensitivity switching during run Uncheck Notes 4 22 Chapter 4 Setup Menu 1 Init E and Final E should be at least 0 01 V apart 2 Depending on the frequency range sometimes the exact frequency can not be obtained If this occurs the closest possible frequency will be applied 3 When frequency is 2 Hz or lower Sample Period should be at least 2 seconds otherwise the system will automatically readjust Sample Period 4 When dc current is high and ac current is low the sensitivity can not be increased because de current will overflow This pr
97. dth 0 0001 to 10 sec 3 or 4 electrode configuration SWV frequency 1 to 100 kHz Current range 250 mA ACV frequency 0 1 to 10 kHz Reference electrode input impedance 1x10 ohm SHACV frequency 0 1 toS kHz Sensitivity scale 1x10 0 1 A V in 34 ranges Automatic potential and current zeroing Input bias current lt 50 pA RDE rotation control output 0 10 V 430A and up Current measurement resolution lt 1 pA Potential and current analog output Cell control purge stir knock Mini tential i tin CV 100 pv pn Ghee shee rn 7 Data length 128K 4096K selectable Potential update rate 1 MHz Data acquisition 16 bit 200 kHz Chassis dimension 12 5 W x 11 D x 4 75 H Frequency resolution lt 0 1 Hz Oscillator box external QCM maximum sampling rate 500 Hz 4 75 L x 2 6 W x 1 55 H Automatic and manual iR compensation Weight 15 Lb Low pass signal filters automatic and manual setting Appendix Techniques for the Model 400A Series Cyclic Voltammetry CV e e e o o Linear Sweep Voltammety LSV e e e Staircase Voltammetry SCV 1 1 Tafel Plot TAFEL O S S S Se f o SS Chronoamperometry CA e e oe o Chonxcouomery CO e e o o Differential Pulse Voltammetry DPV Normal Pulse Voltammetry NPV Differential Normal Pulse Voltammetry DPNV Square Wave Voltammetry SWV AC Voltammetry ACV 2
98. e BA Da Curve 6 Change SolidLine 7 fh fh Curve 7 D Change SoidLine 7 DA h zl Curve 8 O Change SoidLine hz h zl Curve 9 Chance SolidLine x fi gt fi Grid Change fro Color Color Thickness Bkand Change X Y Axis E Change i Color Bar Two Color The following options allow you to select the colors and the legends of the plot Curve Curve 0 represents the currently active data Curves 1 9 are for Overlay Plots The overlapped curves use the color in the order defined here Color You can select the color of the data curve the grid the axis and the background To change these colors click the Change button The system displays the Color dialog box so you can select a color For more information about the Color dialog box refer to your Windows User s Manual To change the color of the text use the Font command Legend Chapter 6 Graphics Menu You can select the legend of the data curve and the grid The legend can be line point circle or any other pattern When a point is chosen for the curve or the grid legend it may not be displayed by certain printers or plotters For instance HP LaserJet IV will not draw a dot in the HPGL mode but it will draw a dot in the raster mode Properly configuring your printer may help Size You can specify the size of the legend or the thickness of the line Interval You can change the data density for the plot The original data density is 1 La
99. e High E or Low E limit is reached the experiment stops 3 Atleast 10 points are required to run the experiment Otherwise you have to reduce the current scan rate or reduce the sampling interval 4 4 Chapter 4 Setup Menu 4 During the experiment the data will be updated in a rate same as data storage interval 5 In general the data storage interval should be chosen according to the length of the experiment The longer the experiment the larger the data storage interval Whenever the data exceed the maximum allowed points the data storage interval will be doubled automatically Therefore data points will not overflow for an unexpected long experiment 4 42 Chapter 4 Setup Menu Parameters for Multi Current Steps In Multi Current Steps ISTEP twelve current steps can be applied and cycled The potential is recorded as the function of time The following diagram shows the current waveform applied as the function of time Steps K 2 3 4 5 l 78 o ho aif 12 pa z 5 D O Cycle 1 Cycle 2 Time s The following are the experimental parameters their range and descriptions Param Range Description Step Sequence 1 12 Step i A 0 25 0 25 Step current Step Time s 0 10000 Step duration High E Limit V 10 10 Potential high limit Low E Limit V 10 10 Potential low limit No of Cycles 1 10000 Number of cycles Smpl Intv s 0 0001 1 Sample interval Notes 1 Ift
100. e between runs This item can also be turn on or off from Purge command under Control menu Stir Between Runs Check this item will allow stir between runs This item can also be turn on or off from Stir command under Control menu Rotate during Deposition Time Check this item will turn the rotator on during the deposition time in the stripping analysis This item can also be turn on or off from Rotating Disk Electrode command under Control menu Rotate during Quiet Time Check this item will turn the rotator on during the quiet time This item can also be turn on or off from Rotating Disk Electrode command under Control menu Rotate during Run Check this item will turn the rotator on when experiment is running This item can also be turn on or off from Rotating Disk Electrode command under Control menu Rotate between Runs Check this item will turn the rotator on between runs This item can also be turn on or off from Rotating Disk Electrode command under Control menu Rotation Speed rpm This parameter set the speed of the rotating disk electrode The parameter range is 0 10000 SMDE Drops Before Run 5 4 Chapter 5 Control Menu The default value of this parameter is 1 Normally the system will issue a combined dispense and knock signal before running experiment to allow a new drop to be formed when the static mercury drop electrode SMDE is used You can change this default condition The parameter range is 0 20 If the p
101. e difference is then measured by reciprocal technique This technique greatly reduces the time need for sampling the QCM signal and gives much better time resolution for the QCM signal With direct counting method a 1 Hz QCM resolution requires 1 second of sampling time and a 0 1 Hz resolution requires 10 seconds sampling time The time resolved mode allows QCM signal to be measured in milliseconds with much better resolution The QCM data can be recorded while the scan rate is at 1 V s The EQCM cell consists of three round Teflon pieces see Figure 1 on next page The total height is 37 mm with a diameter of 35 mm The top piece is the cell top to hold reference and counter electrodes There are also two 2mm holes for manual purging The center piece is the cell body for solution The bottom piece is for mounting purpose Four screws are used to tighten the bottom piece and center piece together The quartz crystal is located between the center and bottom pieces The seal is through two O rings that are pressed together by the four screws mentioned above The diameter of the quartz crystal is 13 7 mm The gold electrode diameter is 5 1 mm Specifications Potentiostat CV and LSV scan rate 0 000001 to 2000 V s Galvanostat Model 440A Potential increment during scan 0 1 mV 100 V s Potential range 10 to 10V CA and CC pulse width 0 0001 to 1000 sec Potentiostat rise time lt 2 us CA and CC Steps 320 Compliance voltage 12 V DPV and NPV pulse wi
102. eck or Automatic sensitivity switching during run Uncheck Notes 1 Init E and Final E should be at least 0 01 V apart 4 20 Chapter 4 Setup Menu 2 Depending on the frequency range sometimes the exact frequency can not be obtained If this occurs the closest possible frequency will be applied 3 When frequency is 2 Hz or lower Sample Period should be at least 2 seconds otherwise the system will automatically readjust Sample Period 4 When dc current is high and ac current is low the sensitivity can not be increased because de current will overflow This problem is more serious when the frequency is relatively low By applying dc current bias it allows higher ac signal amplification A 16 bit DAC is used for this purpose If dc current is not expected to be large and the frequency is high one may not want to bias dc current 5 Both absolute current and phase selective current are available Use the Graph Option command under the Graphics menu to choose data display options 4 21 Chapter 4 Setup Menu Parameters for Second Harmonic A C Voltammetry In Second Harmonic AC Voltammetry SHACV the base potential is increment from Init E towards Final E A sequential sine waveform is superimposed to the base potential The current is sampled when ac signal is applied and its second harmonic components are analyzed using a software lock in amplifier During the experiment only the absolute second harmonic ac current is
103. ectly you have to define the peak shape with the Peak Definition command The peak shape can be Gaussian diffusive or sygmoidal You can also determine if you want to report peak or wave potential half peak or wave potential peak or wave currents or peak area For a Gaussian peak the baseline is determined by two points at each sides of the peak Press the mouse button at one point drag it and release it at the other point A vertical line that connects the peak and the baseline will appear The numerical report is shown at the right side of the plot For a diffusive peak the baseline is determined by extending the foot before the peak To determine the baseline press the mouse button at the foot drag it and release it after passing the peak potential A vertical line that connects the peak and the baseline will appear The numerical report is shown at the right side of the plot Notice that when peak area is reported it is the half peak area For a sygmoidal wave two baselines are needed One is at the foot of the wave and the other is at the plateau of the wave To determine the baselines press the mouse button drag it and release it A vertical line that connects two baselines and crosses the middle of the wave will appear The numerical report is shown at the right side of the plot The following is a typical result from manual peak search This command has a toolbar button Chapter 6 Graphics Menu Peak Definition C
104. edly The following option allows you to determine if the currently active data will be replaced by the baseline corrected data Override Present Data When this box is checked the currently active data will be replaced by the baseline corrected data Otherwise the baseline corrected data will be displayed but will not override the currently active data In this case when the Present Data Plot command under the Graphics menu is invoked the original data reappears 7 9 Chapter 7 Data Processing Menu Data Point Removing Command Use this command to remove unwanted data points from the currently active data You can only remove data points from the beginning or at the end This command presents a Data Point Removing dialog box x Remove Beginning Points fa Remove Ending Points m Cancel MV Override Present Data Help To remove unwanted data points click the OK button The following options allow you to select the parameters for data point removing Remove Beginning Data Points In order to remove the points at the beginning of the data check this box You should also enter the number of data points to be removed in the edit box If the check box is unchecked or if the number of data points to be removed is zero no action will be taken Remove Ending Data Points In order to remove the points at the end of the data check this box You should also enter the number of data points to be remove
105. el for the input voltage setting If wrong ac voltage is connected fuse will blow and instrument may be damaged The correct voltage and line frequency for your region have been set prior to shipment at our factory The standard 2 meter or 6 foot mains cable is fitted with an IEC type connector which can be plugged directly into the power input on the rear panel of your instrument The mains fuse is housed within the power socket When replacing the fuse the user should fully disconnect the instrument from the power supply In the event of repeat failure of the fuse the user should consult with CH Instruments Inc a correct course of action before proceeding further The unit should be placed within 1 5 m of an earthed mains power supply When the instrument is powered on the indicator light on the from panel will be illuminated Rear Panel of instrument my jah iiiad A cE tastruments tnc Bi ai de Made in U S A 1 Power switch On off Switch of unit 2 Fuse State fuse value here 3 Power input Socket IEC type connection socket for mains cable 4 Cooling fan Fuse rating 0 8 A for 110V AC input 0 4 A for 220V AC input Power cord rating 15A for 110V AC input 10A for 220V AC input All other features are clearly labeled on the rear panel itself A 8 Appendix ACV BE CA CC CP CPCR CV DDPA DNPV DPA DPV HMV IMP IMP t IMP E IPAD ISTEP LSV NPV OCPT PSA QCM SCV SHACV
106. eld d Cut a component or connection PAN Add a resistor in Ohm AF Adda capacitor in Farads E Add an inductor in Henry Add a Warburg impedance ca Add a constant phase element Chapter 9 Simulation Menu Change simulation parameters such as frequency range Open an equivalent circuit file for a simulation or a fit lal Save the current equivalent circuit Sim Run the impedance simulator Fit Run the impedance fitting program a Stop the fitting in progress ed Exit the mechanism editor simulation environment The equivalent circuitry drawing is visual To add a component click the component symbol on the tool bar and then click the edit field The component will appear in the edit field If you double click the component you placed in the edit field you can name the component and enter the value of the component You can connect two components by moving the mouse to the left or to the right of a component When the mouse cursor is close to the left or right side of a component a black dot will appear Press the left mouse button when the dot appears and drag the mouse while holding the left mouse button down A trace will appear as you drag the mouse Drag the mouse to the left or to the right of the other component connect If a black dot appears on the left or right side of the other component release the left mouse button A connection should then be made between the two components To remove a component select the component by
107. ensitivity scale Notes 1 Init E and Final E should be at least 0 01 V apart 2 Sampling Width should be no more than half of Step Period otherwise the system will automatically readjust Sampling Width 3 Data sampling always occurs at the end of each step Chapter 4 Setup Menu Parameters for Tafel Plot In Tafel Plot TAFEL potential is scanned from Init E toward Final E The potential may be scanned back The following diagram shows the potential waveform applied as the function of time The logarithm of current is recorded as the function of potential Final E Hold Time Potential V Scan Rate V s Init E Segment 1 Segment 2 Time s The following are the experimental parameters their range and descriptions Parameters Range Description Init E V 10 10 Initial potential Final E V 10 10 Final potential Sweep Segments 1 2 Sweep segments each segments is half cycle Hold Time at Final E s 0 100000 Potential hold time atfer 1st sweep segent Scan Rate V s le 6 0 01 Potential scan rate Quiet Time sec 0 100000 Quiescent time before potential scan Sensitivity A V le 12 0 1 Sensitivity scale Auto Sens Check or Automatic sensitivity switching during run Uncheck Notes 1 Init E and Final E should be at least 0 01 V apart 2 Corrosion rate calculation can be obtained by Special Analysis command under the Analysis menu 4 10 Chapter 4 Setup Menu Param
108. eparator used in the output text file format see above Click Next 5 The Text Import Wizard Step 3 of 3 dialog box will appear Click Finish A spread sheet containing the data will appear 6 Select all data points from the spread sheet 7 Click the ChartWizard button on the toolbar 8 Move the mouse cursor to the spread sheet data area click the left mouse button 9 The ChartWizard Step 1 of 5 dialog box will appear Click Next 10 The ChartWizard Step 2 of 5 dialog box will appear Choose 3D Surface and click Next 11 The ChartWizard Step 3 of 5 dialog box will appear Choose 1 or 2 and click Next 12 The ChartWizard Step 4 of 5 dialog box will appear You should read Data series in Row Use First 1 Row s for Category X Axis Labels Use First Column s for Series Y Axis Labels Click Next 13 The ChartWizard Step 5 of 5 dialog box will appear Decide if you want to add a legend a chart title or Axis Titles for X Y and Z Click Finish 14 A 3D surface plot will appear in the spread sheet data area You can resize the graph by moving the cursor to the corner of the graph until you see the cursor change 3 8 Chapter 3 File Menu to a small dual arrow connected with a diagonal line Press down the left button and drag the mouse You can see that the graph can be enlarged or reduced 15 Once the graph selected click copy it using the Copy command under the Ed
109. er Setting Command Use this command to set potential and current filters The potential filter is used to filter the potential waveforms It is a second order Bessel low pass filter It can be used to filter out transient components An application is to convert the staircase ramp to linear sweep A capacitor might be connected to the feedback resistor of the i E converter to form a low pass RC filter It can remove the high frequency noise at the first hand The signal filter is employed before the gain stage It is a second order Bessel low pass filter The filters are useful in reducing the noise during measurement This command presents a Filter Selection dialog box iE Cony Filter Signal Filter 32 Hz 150 Hz Gane Selection Selection Help Automatic Automatic Line Freq Notch Filter The following options allow you to set filter parameters If you are not familiar with the concept and parameters please choose automatic setting i E Conv Filter This box displays the actual current to voltage converter filter setting Selection Select the i E converter filter cutoff frequency This is an RC filter in conjunction with the current to voltage i E converter The setting of this filter depends on the type of experiment and the time scale of the experiment Choosing automatic will give you the default setting Sometimes certain cutoff frequency can not be selected because for a given sensitivity scale the feedback
110. er accuracy and precision The data quality will be reasonable even the sensitivity scale is not optimized 8 Ifthe scan rate is less than 0 5 V s High resolution ADC can be used to acquire data High resolution ADC usually provide better signal to noise ratio The data quality less depends on the sensitivity setting because of its higher resolution 9 Linear polarization resistance plot can be obtained by the Special Plots command under the Graphics menu Chapter 4 Setup Menu Parameters for Staircase Voltammetry In Staircase Voltammetry SCV potential is increment from Init E toward Final E The potential may be scanned back The following diagram shows the potential waveform applied as the function of time The current is sampled at every potential increment and recorded as the function of potential Final E Potential V q K 4 Init E Sample Width Step Period Segment 1 Segment 2 Time s The following are the experimental parameters their range and descriptions Parameters Range Description Init E V 10 10 Initial potential Final E V 10 10 Final potential Incr E V le 3 0 05 Increment potential of each step Segments 1 1000 Number of scan segments Sampling Width sec le 4 50 Data sampling width for each point Step Period sec 0 001 2500 Potential step period or dropping time Quiet Time sec 0 100000 Quiescent time before potential scan Sensitivity A V le 12 0 1 S
111. er spectrum Analysis e calibration curves calculate the unknown concentration and the slope intercept and correlation of the curve plot the calibration curve save and read the calibration data e standard addition calculate the unknown concentration and the slope and correlation of the standard addition curve plot the standard addition curve save and read the standard addition data e data file report calculate the unknown concentration from the saved data files based on user defined peak potential range species and calibration information An analytical report in text format will be generated maximum four species of interest can be defined e time dependence calculate the unknown concentration as the function of time from the saved data files based on user defined peak potential range and calibration information the concentration as function of time will be reported or plotted Digital Simulation e fast implicit finite difference algorithm e reaction mechanisms 10 predefined mechanisms Model 420A and below any combination involving electron transfer first and second order chemical reactions Model 430A 440A system diffusive or adsorptive maximum equations 12 maximum species 9 simulation parameters standard redox potential rate of electron transfer transfer coefficient concentration diffusion coefficient forward and reverse chemical reaction rate constants temperature electrode area and experimental parameters
112. er you can use Graph Option Color and Legend and Font commands to customize your plot The system displays the Peak Parameter vs Scan Rate Plot dialog box Peak Parameters vs Scan Rate Plot i xj OK Ep From 03 Cancel EpIo 05 Help m Type of Plot m Peak Potential Window ipvs Scan Rate ip vs Sart Scan Rate Ep vs log Scan Rate IV Linear Curve Fitting The following options allow you to set the potential window for peak and select data files Peak Potential Window Enter the possible peak potential range The system only searches for peaks in the specified potential range Once the first peak in this potential range is found it will be used for plotting Type of Plot You can plot the peak current versus scan rate peak current versus square root of the scan rate or peak potential versus the logarithm of the scan rate Linear Curve Fitting Checking this box will allow the data to be fit linearly by the least square method A best fit straight line will also appear on the plot Chapter 6 Graphics Menu Select Files In order to plot data you have to select files Only CV or LSV data will be read Data obtained with other techniques will be ignored Select at least three data files obtained at a different scan rate Chapter 6 Graphics Menu Semilog Plot Command Use this command to display a current potential semilog plot This plot is useful in da
113. ere is a delay The total number of data points will be limited to 64K due to internal memory size limitation Sample interval might be automatically altered to adjust the data points in the reasonable range 7 Ifthe sample interval is longer than 0 002s data will be transferred during experiment Maximum 64K total data points are allowed for each step Sample interval might be automatically altered to adjust the data points in the reasonable range Chapter 4 Setup Menu Parameters for Differential Pulse Voltammetry In Differential Pulse Voltammetry DPV the base potential is incremented from Init E toward Final E A potential pulse is applied The current before the potential pulse and at the end of the potential pulse are sampled The difference of these two current samples is recorded as the function of potential The following diagram shows the potential waveform applied as the function of time and the current sampling scheme a gt Pulse Width 3 J k A Amplitude Final E 7 Init E A kk B Sample Width Pulse Period Time s The following are the experimental parameters their range and descriptions Parameters Range Description Init E V 10 10 Initial potential Final E V 10 10 Final potential Incr E V 0 001 0 05 Increment potential of each point Amplitude V 0 001 0 5 Potential pulse amplitude Pulse Width sec 0 001 10 Potential pulse width Sampling Width sec le 4 10 Data s
114. esesinaacsiaeetas A 6 Limited Warranty setiinaieottenalonen Geach aie valet eccure Stell falta tek ecu Gc 3g A 6 SAE A e cab sa Meera nna E E ocr nena te maares a E A 7 Abbreviation of Electrochemical Techniques cccceccceeeseeseeeteenee ceeeeeseees A 9 The Model 400 Series Electrochemical Quartz Crystal Microbalance A 10 Techniques for Model 600B Series Electrochemical Analyzer cee A 12 Techniques for Model 700B Series Bipotentiostat ce seceeecceseeeteeneeeneeerees A 13 Techniques for Model 800B Series Electrochemical Detector A 14 CHI900B Scanning Electrochemical Microscope ecceeeesteeeterteneeee A 15 Model 1000 Series Multi Potentiostat 0 ccc cece cece eee eeee nena eenenees A 16 Model 1100A Series Power Potentiostat Galvanostat cc eee eeee ees A 17 Model 1200 Series Hand held Potentiostat Bipotentiostat 404 A 18 CHI200 Picoamp Booster and Faraday Cage cccssccssssssccesntcssneceseseneeses A 19 CHIGS4 Multiplexer ss actitaict erties lanes u ragon aian elo CHI680 Amp BOOStED siccseintideriecivadsecntinagdiciaausiantatacdectasieedeassastnckesaenvesag oiendes A 20 CHI682 Liquid Liquid Interface Adapter eeeeeeseeeterteceeeeeetsesceseses A 20 ACCESSO ES 3s cis scna sine ea a ee des a a taster A neal oa aii A 21 Chapter 1 General Information Introduction Model 400A series are
115. eters for Chronoamperometry In Chronoamperometry CA potential is stepped from Init E toward either High E or Low E depending on the Init P N The potential will then step back The following diagram shows the potential waveform applied as the function of time The current is recorded as the function of time Pulse Width Pulse Width Potential V Time s The following are the experimental parameters their range and descriptions Parameters Range Description Init E V 10 10 Initial potential High E V 10 10 High limit of potential scan Low E V 10 10 Low limit of potential scan Init P N Positive or Negative Initial step direction Number of Steps 1 320 Number of potential steps Pulse Width sec le 4 1000 Potential pulse width Sample Interval s 5e 6 10 Sampling Interval Quiet Time sec 0 100000 Quiescent time before potential step Sensitivity A V le 12 0 1 Sensitivity scale Auxiliary Signal Check or Uncheck Simultaneously external signal Recording recording when the sample interval gt 0 005 sec QCM On if Sample Check or Uncheck EQCM enable Interval gt 0 005s 4 11 Chapter 4 Setup Menu Notes 1 High E and Low E should be at least 0 01 V apart 2 If unreasonable High E and Low E are entered the system will automatically readjust them 3 Depending on the Init E High E and Low E value the system will automatically readjust initial step direction 4 The ma
116. etry Parameters dialog box will be displayed so you can select the parameters you want to use Kinetics Command This command allows you to enter the electron transfer kinetic parameters such as standard heterogeneous rate constant standard redox potential or charge transfer coefficient It also allows you to enter the forward and backward rate constant of chemical reactions The Potentials and Rate Constants dialog box will be displayed so you can enter the kinetic parameters Conc Command This command allows you to enter the concentrations and diffusion coefficients of each chemical species involved The Concentration and Diffusion Coefficients dialog box for a diffusive system or the Surface Concentration dialog box for an adsorptive system will be displayed so you can specify the concentration and diffusion coefficients Equilibrium Command This command allows you to view the concentration of each chemical species involved under the given kinetic conditions The Concentration at Equilibrium dialog box will be displayed so you can view the equilibrium state Variables Command This command allows you to enter certain variables such as temperature and electrode area The Simulation Variables dialog box will be displayed so you can enter the variables 9 4 Chapter 9 Simulation Menu Potentials and Rate Constants dialog box This dialog box allows you to enter the kinetic parameters Potentials and Rate Constants oa xj
117. etup Menu Parameters for Bulk Electrolysis with Coulometry In Bulk Electrolysis with Coulometry BE a constant potential is applied and the integrated charge is recorded as the function of time The following diagram shows the potential waveform applied as the function of time and the sample scheme A pre electrolysis may be applied to reduce the interference and background current before the formal electrolysis jets gt T Data Storage Interval eee B Electrolysis E Time s The following are the experimental parameters their range and descriptions Parameters Range Description Electrolysis E V 10 10 Electrolysis potential End Current Ratio 0 100 Stop experiment at this current ratio Data Storage Interval s 0 01 100 Data display and storage interval Preelectrolysis E V 10 10 Preelectrolysis potential Preelectrolysis Time s 0 100000 Preelectrolysis time Notes 1 Preelectrolysis step is allowed before the regular electrolysis This is useful to reduce some residue current The current at the end of preelectrolysis will be regarded as residue current and it will be subtracted from the total charge to give net charge If the preelectrolysis time is set to zero this step is ignored You can stop preelectrolysis at any time by invoke Stop command The regular electrolysis will follow immediately 2 Sensitivity scale will be switched automatically during experiment 3 The current r
118. filters covering 8 decade frequency range Automatic and manual setting Potential and current analog output Cell control purge stir knock Data acquisition 16 bit 200 kHz Maximum data length 128K 4096K selectable Automatic and manual iR compensation Chassis dimension 12 5 W x 11 D x 4 75 H Differences of 1100A Series Models Gyelie Voltammetry CV gt e gt gt linear Sweep Voltammetry LSV e e e gt o Staircase Voltammetry SCV J T S o f o i Tae Plot DARED o S S S S Ei f i i Chronoamperometry CA e gt o Chronocoulomety CO _ e e gt Differential Pulse Voltammetry DPV gt e gt Normal Pulse Voltammetry NPV e gt gt Differential Normal Pulse Voltammetry DPNV J T o Square Wave Voltammetry SWV 1 e gt o SAG Voltammeny AC d S S S e f e i i 2nd Harmonic AC Voltammetry SHACV T T gt Amperometric i t Curve i t Eo Differential Pulse Amperometry DPA Double Differential Pulse Amperometry DDPA Triple Pulse Amperometry TPA Bulk Electrolysis with Coulometry BE _ Sweep Step Functions SSF Multi Potential Steps STEP O Chronapotentiometry CP __ i i a i i i a 3 or 4 electrode configuration Current range 2 A Ref electrode input impedance 1x10
119. g the printer setting in Windows Control Panel Double click the Printer Manager icon to activate the program Choose the Print Setup command under the Option Menu You will be able to set the default to Landscape Other softwares may have their own default settings The global setting will not affect those programs Paper Size Select the size of the paper that will be used to print documents Paper Source Some printers offer multiple trays with different paper sources Specify the tray here Options Chapter 3 File Menu This displays a dialog box where you can make additional choices about printing depending on the specific printer you have selected Exit Command Use this command to end your application session Upon exit some of the system information such as file directory system setup control status macro command data processing options simulation options graphics options color and font will be saved Shortcuts Mouse Double click the application s Control menu button Keys ALT F4 Chapter 4 Setup Menu Technique Command Use this command to select an electrochemical technique This command presents an Electrochemical Techniques dialog box Electrochemical Techniques 7 xi Technique Selection Cancel Cyclic Voltammetry Linear Sweep Voltammetry Help Staircase Voltammetry Tafel Plot Chronoamperometry Chronocoulometry Differential Pulse Yoltammetry Normal Pulse Yoltammetry Differential Normal Pu
120. gment will be ignored 2 For step function if the step time is less than 0 001 sec or if the number of points is less than 3 this segment will be ignored You need to increase step time or decrease sample interval 3 Ifthe scan rate for sweep function is less than 0 5 V s data is transferred and displayed real time 4 Ifthe sample interval for step function is larger than 0 002 sec data is transferred and displayed real time 5 The potential differences of Init E Final E and Step E should be less than 13 1 V 4 37 Chapter 4 Setup Menu Parameters for Multi Potential Steps In Multi Potential Steps STEP twelve potential steps can be applied and cycled The current is recorded as the function of time The following diagram shows the potential waveform applied as the function of time Steps p l lo l3 la s le 7 e lo fio 1a 12 2 E S 2 aw Cycle 1 Cycle 2 Time s The following are the experimental parameters their range and descriptions Param Range Description Step Sequence 1 12 Step E V 10 10 Step potential Step Time s 0 10000 Step Duration Init E V 10 10 Initial potential No of Cycles 1 10000 Number of cycles Smpl Intv s 0 0001 1 Sample interval Quiet Time sec 0 100000 Quiescent time before potential scan Sensitivity A V le 12 0 1 Sensitivity scale Notes 1 Ifthe step time is less than 0 001 sec this step will be ignored 2 Ifthe step time is shorter than
121. gnostic test Instrument Control run experiment real time data display in most cases pause resume during run stop running experiment reverse scan direction during run for cyclic voltammetry repetitive runs automatic data save signal averaging delay or prompt run Status stir purge iR compensation smooth after run RDE and SMDE control status macro commands edit save read and execute a series of commands open circuit potential iR compensation automatic and manual compensation solution resistance double layer capacitance and stability test 1 5 Chapter 1 General Information e analog filter setting automatic or manual setting of potential i V converter and signal filters e cell control purge stir cell on SMDE drop collection pre run drop knock and stabilizing capacitor e step functions multiple cycles of step function generator for electrode cleaning or other purposes e working electrode conditioning before running experiment e rotating disk electrode Model 430 440 rotation speed on off control during deposition quiescent time run and between runs e stripping mode enable disable deposition potential and time stir and purge conditions Graphic Display e present data plot data plot together with header filename parameters and results e overlay plots several sets of data overlaid for comparison e parallel plots several sets of data plotted side by side e zoom in visually selected zoom
122. h Windows The Technique selection field may be truncated if you select English Windows Also oriental Windows does not support certain symbols For instance symbol u will not be displayed properly Choose oriental Windows will use u instead of u Data Length The default data length is 128K The longer the data length the more computer resource will be used It is recommended not to use long data length unless necessary Using long data length will need large computer memory such as 256M 512M RAM or more It will also slow down the system and prohibit other programs to run After you change the data length setting in the System Setup command please exit the program and restart the program so that the data length can be set properly Otherwise the program may crash If the data is acquired and saved with long data length setting but read back with shorter data length setting the program may crash Therefore once you used long data length setting you should not set to shorter data length later Please think carefully before you decide to increase the data length Save retrieve data during run Check this option will allow data to be saved on the hard drive during run In case experiment does not complete due to external interference or interruption miss communication partial data can be recovered This is useful for very slow experiments Hours of experimental data can be recovered This option is not active by default If you do not ru
123. h the System command under the Setup menu You don t have to worry about the baud rate After you alter the setting please exit the program and restart the program It is important to have a computer with a free serial port Most computers specify one or two serial ports However they might be used by mouse and fax modem Usually 2 1 Chapter 2 Getting Started COM 2 is not free It is recommended to use computers with PS 2 mouse or USB mouse Since PS 2 mouse does not use com port you will have COM 1 as a free com port and you can still have the fax modem card installed PS 2 mouse is very popular nowadays If you have the serial port we suggest you not to worry about the USB The USB is really a USB Serial adapter It is a true USB but it converts the USB to serial port by using the software provided by the USB chip vendor It is therefore provide no specific advantages over the serial port The reason we put it there is because some computers such as notebook computers may not have the serial port If you can not locate a free serial port on your computer you can try to use USB port to communication In order to do so you need to change the switch setting inside the instrument and install the driver software Figure 2 1 shows the switch position and how to set the selection Figure 2 1 Serial port or USB port switch selection Near the 100 pin processor chip on the lower left of this figure there is a double pole double th
124. he step time is less than 0 001 sec this step will be ignored 2 Ifthe step time is shorter than the sample interval this step will be ignored 3 Sample interval will be automatically increased if step time cycles sample interval exceeds 128K and if data is transferred after experiment 4 Ifthe sample interval is larger than 0 002 sec data is transferred and displayed real time 5 The experiment will stop if the potential reaches either High E Limit or Low E Limit 4 43 Chapter 4 Setup Menu Parameters for Potentiometric Stripping Analysis In Potentiometric Stripping Analysis PSA a potential controlled deposition step is applied first After deposition the elements cumulated at the electrode surface is stripped out by applying a constant current The potential is recorded as the function of time The following diagram shows the potential waveform during the deposition stage and the current waveform during the stripping stage Data Storage Interval Stripping Current Deposition E Deposition Time Potenital V or Current A Time s The following are the experimental parameters their range and descriptions Parameters Range Description Deposition E V 10 10 Deposition potential Deposition Time sec 0 100000 Deposition time Final E V 10 10 Final potential see note 2 Stripping Current A 0 0 25 Controlled stripping current Sample Interval sec 0 0001 50 Sampling interva
125. icroampere will be expressed as le 6A If you choose Engineering Expression one microampere will be expressed as 1 nA However if you use Oriental Windows versions such as Chinese Japanese Korean the micro symbol will not appear properly you need to set Windows by using the System command under the Setup menu The micro symbol will then be expresses as u The Long Divisions and Short Ticks will allow you to customize the ticks You should freeze the axis scale when you try to use manual setting of ticks 6 1 Chapter 6 Graphics Menu You can also enter text into the data field by double clicking An Insert Text dialog box will be brought up i x Text I Erase 0 x 0 35524 y 1 99824e 00 Rotation 0 Cancel Help x Font Style Size Color Hud Arial Narrow Regular e L Change Default MV Text Display Enabled Monochrome You can enter the text you want to display in the Text field You can erase the text field by clicking the Erase button You can change the X and Y position of the text The X and Y position is the position of the mouse button before you bring up the dialog box by double clicking This will also be the position of the upper left corner of the first letter You can rotate the letter to any angle between 0 and 360 degrees by 1 degree increments You can change the font of the inserted text The font is a global setting It affects all inserted text displayed If you uncheck
126. ide or display the Toolbar choose Toolbar from the View menu oe CHI660A Electrochemical Workstation C 1 File Setup Control Graphics DataProc Analysis Sim View Window Help x Cota S TE mlm ljem BQ Al Ales mfr HA BB 2 For Help press F1 CV 3 Electrode Status Bar Command Use this command to display and hide the Status Bar which describes the action to be executed by the selected menu item or depressed toolbar button the file status and the currently active technique A check mark appears next to the menu item when the Status Bar is displayed The status bar is displayed at the bottom of the application window To display or hide the status bar use the Status Bar command in the View menu The left area of the status bar describes actions of menu items as you use the arrow keys to navigate through menus This area similarly shows messages that describe the actions of toolbar buttons as you depress them before releasing them If after viewing the description of the toolbar button command you wish not to execute the command then release the mouse button while the pointer is off the toolbar button The right areas of the status bar indicate the file status and the currently active technique o gt CHIG60A Electrochemical Workstation C 1 File Setup Control Graphics DataProc Analysis Sim View Window Help oeae TE nmam LQ A Ales m f HA Bl a ey For Help press F1 3
127. in which you want to convert the file s Directories Select the directory in which you want to convert the file s 3 6 Chapter 3 File Menu Text File Format Command Use this command to select the data format in the text mode This command presents a Text File Format dialog box Text File Format mm x xY Separator Vv M Ga a ic Comma Cancel MV Parameters C TAB M Results Space i V Numeric Date C Linefeed Number of Significant Figures 4 Data Point Interval j I DigiSim Format for C and LSY Data Tl Excel 3D Format for SECM Data J Nanoscope Header for SECM data I 3 column impedance data The following options allow you to specify the text file format Memo Check this check box if you want the date time technique name labels and notes to be included in the output text file Parameters Check this box if you want experimental parameters to be added to the output file Results Check this box if you want experimental results such as peak or wave potential current and electrode area to be listed To select the item to be displayed on screen when an experiment is complete execute the Peak Definition command under the Graphics menu Numeric Data Check this box if you want the numeric data points to be listed Separator Select the separator comma TAB space or linefeed to be used between X and Y data colummns The data columns will have one of the following f
128. ion of QCM with electrochemistry EQCM have been widely employed for the determination of metals deposited onto the crystal studies of ion transport processes in polymer films biosensor developments and investigations of the kinetics of adsorption desorption of adsorbate molecules In EQCM experiments the measurements of the various electrochemical parameters such as potential current and charge at the working electrode and the acquisition of the corresponding frequency change are conducted simultaneously Such simultaneous measurements were made possible by employing an experimental setup shown in the Figure on the next page For any model in the CHI400A series the application of a specific potential waveform e g triangular potential waveform for cyclic voltammetric experiments and the subsequent measurement of the current and the frequency counting were carried out with a potentiostat frequency counter which is in turn controlled by a computer The CHI400A series contains a quartz crystal oscillator a frequency counter a fast digital function generator a high resolution and high speed data acquisition circuitry a potentiostat and a galvanostat Model 440A only The QCM is integrated with potentiostat and galvanostat making the EQCM study simple and convenient Instead of measuring the frequency directly the CHI400A series uses time resolved mode The frequency signal of the QCM is subtracted from a standard reference frequency Th
129. isplays the Time Dependence dialog box LTT x Ep From o2 Ep To M oas Cancel Slope 2 2739 Help Intercept 1 65268 Read Peak Shape Gausian gt Repot Data Type 5 Data Type Original Cone C Current Report Name iw Gt Report Y Axis Title Concentration Y Axis Unit prb Plot Header Waste Water Batch 16 Note HA The following options allow you to enter the peak potential windows slope and intercept of calibration curves and select the data files for time dependence report or plot Ep From and Ep To Enter the peak potential range Ep From and Ep To cannot be equal When the program searches for peaks the first peak in the specified range will be selected Slope Enter the slope of the calibration curve for that compound It will be used to calculate the concentration of the compound Each compound has its own slope If Conc report is selected and the slope is zero a warning will be given Intercept Enter the intercept of the calibration curve for that compound It will be used to calculate the concentration of the compound Each compound has its own intercept Peak Shape You can select the peak shape according to the property of your data The peak shape can be Gaussian diffusive or sygmoidal Data Type 8 7 Chapter 8 Analysis Menu You can select original data semi derivative or first derivative to report the concentration Y Axis Title Enter the Y axis title
130. istor You can use CV to see if you obtain a straight line with a slope of voltage resistance CHI682 Liquid Liquid Interface Adapter Liquid liquid interface study is very important in understanding the charge transfer chemical sensor drug release solvent extraction and others Liquid liquid interface study usually involves two reference electrodes and two auxiliary electrodes The modified potentiostat controls the potential difference of the two reference electrodes in two phases while measuring the current passing through two auxiliary electrodes The CHI682 Liquid Liquid Interface Adapter is compatible with our model 700A series It is fully automatic and transparent to users Most electrochemical techniques can be used However it does not have galvanostat and bipotentiostat functions Please notice that for model 400 600A 600B 600C 700B 700C 800B 900B 1100 1100A series 4 electrode configuration will allow liquid liquid interface measurement to be made directly without using CH1682 Liquid Liquid Interface Adapter A 20 Appendix Accessories Part No Description Unit PartNo Description Unit CHI17 25 um dia Platinum SECM Tip CHII17P 25 um dia Platinum SECM Tip 3 pk CHI18 1 5 um dia Platinum SECM Tip CHI120 Electrode Polishing Kit 7 CHI125 Polished Bounded Mounded 100A Cr 1 1000 A Gold Crystal for EQCM CHI127 EQCM Cell CHI128 Reference Electrode for EQCM Cell 1 1 CHI129 Pt Wire Coun
131. it menu or click the Copy button on the toolbar You can then paste the graph into a word processor for further usage or print Please be aware that exporting the graph to a picture format like Bitmap or JPEG in Excel and subsequently inserting the picture into the word processor document generally reduces the final files s size If the data density is so high that the lines that connect the data points cannot be seen clearly set the data point interval to more than 1 Nanoscope Header This is only for SECM image data When this box is checked a header will be added to render the text data file readable directly by the Nanoscope software Veeco Instruments Inc Santa Barbara CA to create a 3D image However Veeco Instruments regularly updates the Nanoscope software your generated file may therefore nit be readable if your version is older than that used in the CHI900B software 3 9 Chapter 3 File Menu Import Text File Command Use this command to import text files Currently it will read the CHI text file format as well as BAS text file format This command presents an Import Text File dialog box Import Text File 2 x Files of type Data Files txt x Cancel For CHI files the memo and the parameters are required to import a text file Since some BAS parameters are different from the CHI parameters BAS parameters will be adjusted to be CHI parameters Chapter 3 File Menu Print Command Use
132. ity scale 1 Init E and Final E should be at least 0 01 V apart 2 Forward reverse and difference currents are recorded Use the Graph Option command under the Graphics menu to choose data display options 4 19 Chapter 4 Setup Menu Parameters for A C Voltammetry In AC Voltammetry ACV the base potential is increment from Init E towards Final E A sequential sine waveform is superimposed to the base potential The current is sampled when ac signal is applied and analyzed using a software lock in amplifier During the experiment only the absolute ac current is displayed After experiment the phase selective current at any phase angle are also available for display The following diagram shows the potential waveform applied as the function of time Final E Amplitude Ne Potential V Init E J k Sample Period Time s The following are the experimental parameters their range and descriptions Parameters Range Description Init E V 10 10 Initial potential Final E V 10 10 Final potential Incr E V 0 001 0 05 Increment potential of each point Amplitude V 0 001 0 5 A C amplitude Frequency Hz 0 1 10000 A C frequency Sample Period sec 0 1 50 Data sampling period or dropping time Quiet Time sec 0 100000 Quiescent time before potential scan Sensitivity A V le 12 0 1 Sensitivity scale Bias DC Current off range on Enable dc current bias during run Auto Sens Ch
133. ive data This command does not check the type of data If both X and Y values fall into the plot scale the data point will be plotted The Graph Option Color and Legend and Font commands allow you customize your data plot This command is disabled if there is no currently active daya This command is also disabled unless the current plot is a parallel plots Chapter 6 Graphics Menu Zoom In Command Use this command to zoom in the data plot This is a toggle switch A check mark appears next to the menu item when the zoom in function is enabled The Zoom In toolbar button will be pressed in When you move the mouse cursor in the data plot area an upper arrow cursor appears To zoom in press the mouse button at one corner drag it to the diagonal corner of the area you want to have a closer view at and release the mouse button To zoom out click the Zoom In command again This also disables the zoom function This command has a toolbar button 6 9 Chapter 6 Graphics Menu Manual Result Command Use this command to report peaks or wave potentials currents and area manually You can determine the baseline for a peak or wave visually This is a toggle switch A check mark appears next to the menu item when the manual result function is enabled The Manual Result toolbar button will be pressed in When you move the mouse cursor in the data plot area an upper arrow cursor appears In order to report a peak or wave corr
134. l Quiet Time sec 0 100000 Quiescent time before taking data Notes 1 Ifsample interval is less than 0 002 s Total 64K data points are allowed The data density equals to the Run Time 64000 2 Ifthe final potential is reached the experiment will automatically stop 3 Ifthe controlled stripping current is set to zero the counter electrode is actually not connected 4 44 Chapter 4 Setup Menu 4 Ifthe controlled stripping current is smaller than 1 0e 10A no current will flow during experiment 5 You do not have to worry about the current polarity The system will automatically assign the current polarity according to the deposition potential and the final potential Positive current is for reduction Negative current is for oxidation 6 In general the data storage interval should be chosen according to the length of the experiment The longer the experiment the larger the data storage interval reduce the stripping current Chapter 4 Setup Menu Parameters for Open Circuit Potential Time The system displays a Open Circuit Potential Time Parameters dialog box Parameters for Open Circuit Potential Time xj Run Time sec 400 OK Sample Interval sec fo pom High E Limit M f Low E Limit VJ 0 0 dii Help The following are the experimental parameters their range and descriptions Parameters Range Description Run Time sec 0 1 500000 E
135. l the files to the C CHI directory After installation you should find CHI EXE executable program CHI HLP help file and some test data files BIN in the C CHI directory It is safe to delete any files in the C CHI directory later In the CD ROM you can also find the electronic version of the User s Manual and the USB Driver Hardware The system hardware installation is also easy and simple After unpacking the instrument you should check the power lines The A C voltage was preset in the factory and is indicated in the serial number label on the back panel If the A C voltage is correct connect the instrument to the power through the power cord Communication between the instrument and PC is through RS 232 serial port or USB port However you can only use one of them The default is the serial port If your computer has a free serial port 9 pin male connector it can directly communicate with the instrument You do not need to install extra software If your computer does not have a serial port you can use USB port for communication However you need to change the jumper position inside the instrument and install software If you use serial port for communication connect the Com Port 25 pin connector at the rear panel to the serial port of your PC The cable is a 9F 25M serial cable comes with the instrument You may need to set the software to a proper port The default is COM 1 This setting can be altered throug
136. later segments will be displayed during the run but will not be stored 6 The current polarity can be switched either at the specified potential or at the specified time Cathodic and anodic time setting can be different On the other hand even with time priority selected if the limiting potential is reached the current polarity will still be inversed in order to protect the electrode 4 40 Chapter 4 Setup Menu Parameters for Chronopotentiometry with Current Ramp In Chronopotentiometry with Current Ramp CPCR a current ramp can be applied to the working electrode The potential is recorded as the function of time The following diagram shows the current waveform applied as the function of time Final Current Current A Scan Rate A s Init Current Time s The following are the experimental parameters their range and descriptions Param Range Description Init Current A 0 25 0 25 Initial current Final Current A 0 25 0 25 Initial current Scan Rate A s le 10 0 01 Current scan rate Sample Interval sec 0 0025 32 Sampling interval High E Limit V 10 10 High potential limit value Low E Limit V 10 10 Low potential limit value Data Storage Intvl sec 0 0001 32 Data storage interval Notes 1 Initial Current and Final Current should be at least 1e 9A apart 2 Positive current is for reduction and negative current is for oxidation During the course of reduction if th
137. ld be either held at Cleaning Uncheck a constant potential or open circuit Init E V 10 10 Initial potential during quiescent time Number of Cycles 10 100000 Number of Repetitive Cycles Quiet Time sec 0 100000 Quiescent time before taking data Scales During Run 1 2 3 Number of current display scales Sensitivity A V le 12 0 1 Sensitivity scale Notes 1 The experimental sequence follows the first DPA cleaning first pulse and second pulse then the second DPA cleaning first pulse and second pulse This sequence will be repeated until the total running time is reached or interrupted by user There is no data acquisition during cleaning step If the cleaning time is zero this step will be ignored Data are sampled for first and second pulses and the difference is reported Two sets of data will be obtained 2 The data is sampled at later 1 2 period of pulse 1 and 2 The longer the pulse width the longer the sample interval Long sample interval will have better signal averaging and less noise 3 During experiment whenever the data exceed the maximum allowed points the data storage interval will be doubled automatically Therefore data points will not overflow for an unexpected long experiment 4 When 1 current scale is displayed during run it will automatically fit the data in scale When 2 current scales are displayed during run they is 1 100 and 1 10 of full scale When 3 current scales are displayed during run they i
138. lease see Smoothing and Differentiation of Data by Simplified Least Squares Procedures Anal Chem 36 1627 1639 1964 FT Cutoff 1 s or 1 V Specify the filter cutoff frequency For a time based experiment including CA CC TB 1 s or Hz is the unit For voltammetry the unit is 1 V Its physical meaning is how many signal cycles are allowed in one volt of potential range The lower the cutoff the better the smoothing effect will be but it may also cause more distortion Fourier transform smoothing is done by a procedure proposed by D E Smith et al For more detail about the algorithm please see Some Observations on Digital Smoothing of Electroanalytical Data Based on the Fourier Transformation Anal Chem 45 277 284 1973 In general Fourier transform smoothing is very effective The distortion may be minimal if the signal band is well separated from the noise band On the other hand this method is relatively more time consuming Smooth After Run When this box is checked automatic smoothing after run is enabled Certain techniques such as TAFEL BE and IMP do not allow smoothing This option can also be turned on or off from the Run Status command under the Control menu Override Present Data 7 1 Chapter 7 Data Processing Menu When this box is checked the currently active data will be replaced by smoothed data Otherwise the smoothed data will be displayed but will not override the currently active data
139. lse Yoltammetry Square Wave Voltammetry A C Yoltammetry 2nd Harmonic 4 C Yoltammetry Amperometric i t Curve Differential Pulse Amperometry Double Differential Pulse Amperometry Triple Pulse Amperometry Bulk Electrolysis with Coulometry Hydrodynamic Modulation Voltammetry Sweep Step Functions Multi Potential Steps Chronopotentiometry Chronopotentiometry with Current Ramp Multi Current Steps Potentiometric Stripping Analysis Open Circuit Potential Time Quartz Crystal Microbalance Z Polarographic Mode The following options allow you to select an electrochemical technique Technique Selection Select the electrochemical technique you want to use This box lists the techniques available in the instrument Double clicking the technique you want to select is equivalent to selecting the technique and clicking the OK button Polarographic Mode Check this box will enable the polarographic mode In the polarographic mode the mercury drop will be allowed to grow and be dislodged for every data point Only a few techniques are allowed to have polarographic mode Sampling Current Staircase Polarography SCP Differential Pulse Polarography DPP Normal Pulse Polarography NPP Differential Normal Pulse Polarography DNPP A C Polarography ACP and Second Harmonic A C Polarography SHACP 4 1 Chapter 4 Setup Menu Once polarographic mode is enabled stripping mode is disabled In order to set stripping mode by
140. m will automatically readjust Pulse Width 4 Sampling Width should be no more than half of Pulse Width otherwise the system will automatically readjust Sampling Width 4 18 Chapter 4 Setup Menu Parameters for Square Wave Voltammetry In Square Wave Voltammetry SWV the base potential is increment from Init E towards Final E A square wave potential is superimposed to the base potential The base potential increments after each cycles of the square wave The current at the end of forward and reverse steps are sampled These two current are recoded as the function of the base potential During the experiment only the difference of two current samples is displayed After experiment the forward and reverse current are also available for display The following diagram shows the potential waveform applied as the function of time and the current sampling scheme Potential V bs tom cee Final E 4 kd k 1 Frequency k Sample Width Time s The following are the experimental parameters their range and descriptions Parameters Init E V Final E V Incr E V Amplitude V Frequency Hz Quiet Time sec Sensitivity A V Notes Range 10 10 10 10 0 001 0 05 0 001 0 5 1 100000 0 100000 le 12 0 1 Description Initial potential Final potential Increment potential of each point Square wave amplitude Square wave frequency Quiescent time before potential scan Sensitiv
141. mbols and lines to connect symbols save you data with two different names and select proper legends by using Color and Legend command To freeze the scale use the Graph Option command The system displays the Overlay Data Display dialog box so you can select the data files you want to plot along with the data in the XY Data Array Editor Multiple files can be selected The plot will be scaled according to the data in the XY Data Array Editor If both X and Y values fall into the plot scale the data point will be plotted Parallel Plot Use this command to plot multiple sets of data in a parallel mode The system displays the Parallel Data Display dialog box so you can select the data files you want to plot along with the data in the XY Data Array Editor Multiple files can be selected Each plot will be automatically scaled according to each data set read from the disk unless the scale is frozen In the latter case all the plots will have the same frozen scale To freeze the scale use the Graph Option command Plot Use this command to plot the XY Data Array Editor The plot will be automatically scaled according to the data range To freeze the scale use the Graph Option command XY Title Enter the X and Y titles Unit Enter the unit or dimension of the customized X and Y axis titles Header This is the header text editor box Enter your header here To display the header on top of the plot check the Header box using the Gra
142. mpt will be issued before each run except the 1st run The instrument will wait until you respond When External Trigger is selected the instrument will wait for external trigger signal External trigger is an active low signal and can be applied to the Pin 13 of the Cell Control port on the rear panel Base Filename 5 8 Chapter 5 Control Menu Enter the base filename Maximum 5 characters are allowed After run the data is saved The run number will be attached to the base filename i e filenameN where N is the run number from 1 to 99999 If the base filename is not specified a warning will be given If you continue the system will run experiments without saving the data The browse button allows user to choose the base filename from different directory Immediate Channel Set It allows you to set arbitrary channel immediately You can then exit the dialog box and run experiment for that particular channel Run Multiplexer Press this button will run experiment in a sequence of selected channels using the CHI1684 Multiplexer If you provide the base file name the file will automatically saved after each run as base filename channel number bin For instance if you set base filename as test and you select channels 3 8 23 and 58 Run Multiplexer will run 4 experiments and save data as test3 bin test8 bin test23 bin and test58 bin Before execution the system will check the filename If existing data files have a same b
143. ms These are the most common reaction mechanisms The first item is User Input Only certain high end models will accept user defined mechanisms You can obtain other mechanisms from the predefined mechanisms For instance the EEC ECC and CEC mechanisms can be obtained from an ECEC mechanism by defining some of the kinetic parameters as zero If you set the heterogeneous electron transfer rate ko to zero the corresponding electron transfer step will have no effect Similarly if you define the forward and reverse rate constants of a chemical reaction to zero the corresponding chemical reaction will be ignored When you click the predefined reaction mechanism the mechanism will appear in the Mechanism Edit box If User Input is clicked the Mechanism Edit box will be emptied System under Study The software will simulate either diffusive or adsorptive system The diffusive system assumes planar diffusion The adsorptive system assumes that the adsorption obeys the Langmuir isotherm and that both oxidized and reduced forms are strongly adsorbed Dimensionless Current 9 2 Chapter 9 Simulation Menu Checking this box will allow the system to calculate the dimensionless current This might be useful when comparing a particular simulation to other theoretical results When this box is unchecked the current will be calculated according to the concentration electrode area and time scale of the experiment Initial Concentration
144. n be used to acquire data High resolution ADC usually provide better signal to noise ratio The data quality less depends on the sensitivity setting because of its higher resolution Chapter 4 Setup Menu Parameters for Linear Sweep Voltammetry In Linear Sweep Voltammetry LSV potential is scanned from Init E toward Final E The following diagram shows the potential waveform applied as the function of time The current is recorded as the function of potential Potential V Init E Final E Scan Rate V s Time s The following are the experimental parameters their range and descriptions Parameters Init E V Final E V Scan Rate V s Sample Interval V Quiet Time sec Sensitivity A V Auto Sens if Scan Rate lt 0 01V s Scan Complete Cycles Auxiliary Signal Recording High Resolution ADC Range 10 10 10 10 le 6 2000 0 001 0 064 0 100000 le 12 0 1 Check or Uncheck Check or Uncheck Check or Uncheck Check or Uncheck Description Initial potential Final potential Potential scan rate Data sampling interval Quiescent time before potential scan Sensitivity scale Automatic sensitivity switching during run Scan complete cycles Simultaneously external signal recording when the scan rate is less than 0 25V s Use high resolution ADC when scan rate is less than 0 5 V s Chapter 4 Setup Menu QCM On if Scan Check or EQCM enable Rate lt 0 25V s
145. n enter the type of the reference electrode in the edit box after the Ref Electrode prompt Header This is the header text editor box Enter your header here To display the header on top of the plot check the Header box in the Screen and or Printer options Note This is the note text editor box Enter your note here The note is not displayed on the screen but will be shown as data information and saved in the data file It allows Chapter 6 Graphics Menu you to put more comments about the experiment and remind you later about the purpose and the conditions of the experiment This command has a toolbar button m E C Chapter 6 Graphics Menu Color and Legend Command Use this command to edit graphic plot color and legends You can change the color of the background the axis the grid and thedata curve You can also change the legend of the data curve and the grid The color and legend will be saved when you exit the program and will be reloaded when you restart the program To change the text color please use the Font command This command presents a Color Selection dialog box Color Selection E X g a Color Legend Size OK Curve 0 Change SolidLine hi i lt Curve 1 Change SoidLine Mz Mz Es Curve 2 E Change SoidLine h x h x te Curve 3 Change SolidLine gt hzl Ma Defaut Curve 4 K Change SoidLine ha Ma Monochrome Curve 5 E Change SoidLin
146. n very slow experiments you can re run the experiment if the experiment is interrupted by accident To retrieve experimental data of last run you should use Retrieve command under the File menu Present Data Override Warning If your experimental data is not saved before running a new experiment or opening an existing file on the disk your unsaved data will be overridden This option will allow system to issue a warning before the data is lost Save Text File As Well Normally only binary data files is saved Binary file contains more information including experimental control information but small in size This option allows you to save text file as well whenever you save the binary data This is useful for those who want to export data to other software such as spreadsheet software Erase ADC Calibration Coefficients The analog to digital converter ADC calibration coefficients are stored in the instrument non volatile memory ADC calibration is carried out in CH Instruments 4 49 Chapter 4 Setup Menu before the instrument is shipped You use this command only if you want to recalibrate the ADC After you erase ADC calibration coefficients you will see a prompt of ADC calibration when you run next hardware test or experiment 4 50 Chapter 4 Setup Menu Hardware Test Command Use this command to test the system hardware The system will test ROM RAM and analog circuitry After the test the system will display the Hardware
147. nd Harmonic AC Voltammetry SHACV Amperometric It Curve d Differential Pulse Amperometry DPA Double Differential Pulse Amperometry DDPA Triple Pulse Amperometry TPA Bulk Electrolysis with Coulometry BE _ Hydrodynamic Modulation Voltammetry HMV Sweep Step Functions SSF MultiPotential Steps STEP Chronopotentiometry CP Chronopotentiometry with Current Ramp CPCR Potentiometric Stripping Analysis PSA Open Circuit Potential Time OCPT Quartz Crystal Microbalance QCM ___ ooo aalvanostat S O O RDE control 0 10V output Full version of CV simulator Limited version of CV simulator PR Compensation Od S Corresponding polarographic mode can be performed amp Corresponding stripping mode can be performed Phase selective data are available Reference Auxiliary Potentiostat Galvanostat Frequency Counter Oscillator Computer ae Cell Bottom Crystal Figure 1 EQCM setup Appendix Techniques for the Model 600C Series Electrochemical Analyzer ae e o o o o o o o o o Corresponding polarographic mode can be performed amp Corresponding stripping mode can be performed Phase selective data are available Dynamic Range of Some Experimental Parameters Potential V 10 to 10 Current A 0 to 0 25 Sensitivity A V 1x10 to 0 1
148. ng and Differentiation of Data by Simplified Least Squares Procedures Anal Chem 36 1627 1639 1964 Override Present Data When this box is checked the currently active data will be replaced by the derivative data Otherwise the derivative data will be displayed but will not override the currently active data In this case when the Present Data Plot command under the Graphics menu is invoked the original data reappears This command has a toolbar button 7 3 Chapter 7 Data Processing Menu Integration Command Use this command to integrate the currently active data After performing integration the Y axis has a unit of Y unit x X unit For voltammetry it is AV For an i t curve it is As coulomb The new unit is not explicitly expressed but you should be aware of it This command presents an Integration dialog box Integration xj OK To perform integration click the OK button The following options allow you to select the parameters for integration Override Present Data When this box is checked the currently active data will be replaced by the integrated data Otherwise the integrated data will be displayed but will not override the currently active data In this case when the Present Data Plot command under the Graphics menu is invoked the original data reappears 7 4 Chapter 7 Data Processing Menu Semiinteg and Semideriv Command Use this command to perform semi integral
149. ng electrode The white one is for reference electrode The red one is for counter electrode The black one is for sensing electrode of the 4 electrode configuration The 4 electrode configuration can be turned on or off by check or uncheck the 4 Electrodes box using the Cell command under the Control menu When the 4 electrode option is on you should connect the black lead to the working electrode short the green and black leads together The 4 electrode configuration is useful for liquid liquid interface measurements or when the current is relatively high It helps eliminate the resistance about 0 2 0 3 ohm due to the connectors relays and printed circuit board traces With the Amp Booster connected the cell control signals such as purge knock and stir are disabled The Amp Booster will also allow low current measurements The current down to 10 pA can be measured It is comparable with the CHI6xxA B alone You may need to use Faraday cage to eliminate line frequency noise when the scan rate is above 50 mV s The frequency responses of the Amp Booster is somewhat lower than the CHI6xx A B C instruments In case of high speed experiments such as impedance measurements the Amp Booster should be disconnected If you think there might be something wrong with the hardware please do hardware test with Amp Booster disconnected If the CHI6xxA B C passes the test you can then connect the Amp Booster and test the Amp Booster with a standard res
150. nt the modified data point to be release the mouse button The old point will be erased and a new point will appear at the new position The following option allows you to select the data set you want to modify and to determine if the currently active data will be replaced by the modified data Data Set Segment Choose the data set you want to modify This selection depends on the electrochemical technique used Override Present Data When this box is checked the currently active data will be replaced by the modified data Otherwise the modified data will be displayed but will not override the currently active data In this case when the Present Data Plot command under the Graphics menu is invoked the original data reappears Chapter 7 Data Processing Menu Bkgnd Subtraction Command This command allows you to calculate the difference between two data sets First you have to measure the blank solution save the data file Then run the sample You can now use this command to do a background subtraction In order to do a background subtraction the background data should be the same type of experiment and the same X data array Otherwise an error message will be issued and the command will be terminated This command presents a Background Subtraction dialog box so you can select the background data file that will be subtracted from the currently active data Background Subtraction IMPE1 IMPE2 NPVO IMPE3 OC
151. ntil the desired result is attained The system displays the Font dialog box so you can select the font For more information about Font dialog box refer to your Windows User s Manual Pressing the Default button will reset all fonts to the system default This command has a toolbar button Chapter 6 Graphics Menu Copy to Clipboard Command Use this command to copy the plot to clipboard You can then paste it into a word processor or any other windows based prgram This command will work during a run or a digital simulation This command has a toolbar button Chapter 7 Data Processing Menu Smoothing Command Use this command to smooth the currently active data This command presents a Smoothing dialog box ee lt Method Selection Cancel C Fourier Transform Smoothing Help Least Square Point 7 Smooth After Bun ET Cutoff 1s or 17 30 IV Override Present Data To perform the smoothing click the OK button The following options allow you to select the mode and parameter for smoothing Method Selection Select the smoothing method least square or Fourier transform smoothing Least Square Point The Savitzky and Golay algorithm is used in this technique An odd number of points from 5 to 49 should be used for smoothing The more points the better the smoothing effect will be but it may cause larger distortion For more detail about Savitzky and Golay algorithm p
152. oblem is more serious when the frequency is relatively low By applying dc current bias it allows higher ac signal amplification A 16 bit DAC is used for this purpose If dc current is not expected to be large and the frequency is high one may not want to bias dc current 5 Both absolute current and phase selective current are available Use the Graph Option command under the Graphics menu to choose data display options 4 23 Chapter 4 Setup Menu Parameters for Amperometric i t Curve In Amperometric i t Curve i t a constant potential is applied and the current is recorded as the function of time The following diagram shows the potential waveform applied as the function of time and the sample scheme oan gt 3 Sample Interval p g eeee B O InitE _ a 0 Run Time Time s The following are the experimental parameters their range and descriptions Parameters Range Description Init E V 10 10 Initial potential Sample Interval sec Se 6 50 Data sample interval Run Time sec 0 001 5e5 Total measurement time Quiet Time sec 0 100000 Quiescent time before taking data Scales During Run 1 2 3 Number of current display scales Sensitivity A V le 12 0 1 Sensitivity scale Auxiliary Signal Check or Simultaneously external signal Recording Uncheck recording when the sample interval is greater than 0 005 s High Resolution ADC Check or Use high resolu
153. ocoulometry CC potential is stepped from Init E toward Fianl E The potential may step back The following diagram shows the potential waveform applied as the function of time The charge passing through the working electrode is recorded as the function of time Pulse Width Pulse Width Potential V Time s The following are the experimental parameters their range and descriptions Parameters Range Description Init E V 10 10 Initial potential Final E V 10 10 Final potential Number of Steps 1 320 Number of potential steps Pulse Width sec le 4 1000 Potential pulse width Sample Interval s 5e 6 10 Sampling Interval Quiet Time sec 0 100000 Quiescent time before potential step Sensitivity A V le 12 0 1 Sensitivity scale Notes 1 Init E and Final E should be at least 0 01 V apart 2 The maximum potential step range is 13 1 V 3 Shorter sample interval will increase data density but will reduce the signal noise ratio If earlier transient data is important shorter sample interval is recommended If 4 13 Chapter 4 Setup Menu the later part of data is of interest longer sample interval is recommended However minimum 1000 points per step are required unless sampling rate does not allow it 4 During the run an Overflow warning might appear This is due to the current transient immediately after the potential step If the intercept that gives information of double l
154. olayer adsorption for long period of time you need to control temperature The frequency of the crystal is very sensitive to the temperature particularly if the crystal is in the electrolyte solution Figure 2 3 is a data file we obtained We put the EQCM cell in a very large thermal bath We started at room temperature We tried to control the temperature at 30 degree C Initially the temperature rises monotonically However we see big and fast fluctuation of the frequency After 3e4 second the temperature is settled For the next 12 hours the drift is less than 2 Hz If you do not do electrochemistry while you do QCM and if you need to add samples you need to get a QCM flow cell with pump and sample injection device CHI440 Time Resolved Electrochemical Quartz Crystal Microbalance Qcmdrift bin File Setup Control Graphics DataProc Analysis Sim View Window Help oses Ti gt lfm le alme fie wl e zax Crystal in Water Thermostatic bath settled at 3e 4 sec Mar 30 2001 08 42 03 200 Pe er ae ee a YEN We E EY Yee TN OE De ee a eer ene eH Ya emer ee Wael oe ee ee dL Se SY Tech QCM rx File Qemdrift bin 1804 r Smpl Intvi s 0 8 Run Time s 5e 5 1604 QCM f0 Hz 7994868 7 No 140 i T VAIN f Z awf 5 Jil f ad 1004 i XG E ki jji A x 80 ida ol E R 60 J 40 F 20 04 ee Ee Py z oe 3 0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0 Time 1e 4sec
155. olute ac current is displayed After experiment the phase selective current at any phase angle are also available for display The ac current is sampled at every potential increment and recorded as the function of potential Final E Potential V J k Incr E Rotation speed modulation amp data sampling Init E Time s The following are the experimental parameters their range and descriptions Parameters Range Description Init E V 10 10 Initial potential Final E V 10 10 Final potential Incr E V 0 001 0 02 Increment potential of each step Rotation Rate rpm 0 10000 Center rotation rate Modul Frequency Hz 1 5 Modulation frequency Modul Amplitude rpm 0 3600 Modulation Amplitude see note 2 Number of Cycles 1 10 Number of modulation cycles Quiet Time sec 0 100000 Quiescent time before potential scan Sensitivity A V le 12 0 1 Sensitivity scale Notes 1 Init E and Final E should be at least 0 01 V apart 2 The actual rotation rate in hydrodynamic modulation is 12 1 2 1 2 3 0 A sin ot 4 34 Chapter 4 Setup Menu Notice that the modulation function is not a sine wave but more complicated On the other hand it is still a periodic waveform at frequency o Modulation Frequency The rotation rate is fluctuated around Rotation Rate but the amplitude of the fluctuation is not symmetric The input parameter Aw Modulation Amplitude is really not the amplitude
156. ommand Use this command to define the peak shape Gaussian diffusive or sygmoidal You can also determine if you want to report peak or wave potential half peak or wave potential peak or wave currents or peak area The peak definition is used for both automatic and manual result reports This command presents a Peak Definition dialog box Peak Definition E x Peak Shape Report Option 7 eaen Peak or wave potential Cancel PETS Half peak potential Diffusive Help en Iv Peak or wave current c Sygmoidal V Peak area Peak or wave search potential range VJ 0 0 00 0 5 The following options allow you to define the peak shape and determine what parameters need to be reported Peak Shape You can select the peak shape according to the property of your data The peak shape can be Gaussian diffusive or sygmoidal The peak shape is assumed from the electrochemical technique Each time you change the technique a default value is assigned to the peak shape However you can change this setting Report Option You can determine if you want to report peak or wave potential half peak or wave potential peak or wave currents or peak area Peak or Wave Search Potential Range Depending on the peak shape the peak search potential range can be adjusted For a broader peak or wave the search potential range should be larger and vice versa The search potential range includes
157. ompensation for next run is enabled You may not be able to enable iR compensation if the automatic compensation is set and the iR compensation test has not been conducted or the sensitivity scale has been altered This option can also be turned on or off from Run Status command under Control menu iR Comp Enable If the option Once is chosen the iR compensation will only be applied to next run and then disabled If you want the same compensation conditions to be applied to the consecutive runs choose Always option Click the proper radio button to select the option iR Comp Mode You can choose automatic iR compensation or manual iR compensation The automatic iR compensation will be based on the iR compensation test results You can also choose manual iR compensation by entering the resistance value you want to compensate Click the proper radio button to select the option Manual Compensation Resistance If you select manual iR compensation you should enter the resistance value that you want system to compensate Be careful about the compensation level If the compensation level is close or exceeds the actual solution resistance the potentiostat will oscillate Please also notice that the maximum allowed resistance compensation may be limited to the feedback resistor of the i E converter This parameter has no effect if automatic iR compensation is selected This command has a toolbar button Chapter 5 Control Menu Filt
158. oncentration and Diffusion Coefficients dialog box ee ee eeeeeeeeeee 9 6 Surface Concentration dialog box 2scccuctsecscdacs anther Aienueiaiacsissace 9 7 Concentration at Equilibrium dialog DOX 0 ceceeceeeceeseeeseeeeeceteeeeeeenees 9 8 Simulation Variables dialog DOX e cc eeccesceeseceseeeeseeeseeceaeceeeeeeaeeneeensees 9 9 Sim lat Command ss setssaccisestandavaasadeteds saddens evens artan iasa ALERE Ea rE ina 9 10 AC Impedance Simulator iesise naient aii 9 11 Chapter 10 View Menu Data Information Command ssssssseseesseessesessseesseserssessessesstesseestesresseesseseessresse 10 1 Data Listing Command daresirisgecini nonton aa r A a mes 10 3 Equation Command rerai ananin ana dite a a a ain ede a 10 4 Clock Command spiana ia iiare nat o cao NAE AER a R a AERE 10 5 Toolbar OO a a a E a a a a A raa aai ais 10 6 Status Bar Commandes roren tae a A acca Seddeedshacdaeekadebcdatacveeebecdecuaedeucetls 10 6 Chapter 11 Help Menu Help Topics Command in 2ccceu ecemnaanae ates aae uceseanieeouaeatn 11 1 About Command osissa a lea kk laa ae ad uk ata ea aa ERNE 11 2 Appendix Cables atid Connections yaks sre siteatdarsahavanadaedessdesas vivgandunssdhaedeadeadeesiesicinnends A 1 Instructions of Software Update 2s s idscsseuieansasecuscssdancirtartadanauien A 3 Tro ble Shooting sirrien anessa taaa as oa nE ERa ERREA EA A 4 Maintenance and Service cir snccistsacaccuteava vas ecasina tee aeaaetea sees ada sane eeauone
159. only if the electrochemical cell can be equivalent to a solution resistance in series with a double layer capacitor The range of Test E is 10V 10V You may adjust the potential step amplitude The larger the amplitude the higher the signal to noise ratio However too large amplitude may cause faradaic current to flow A step amplitude of 0 05V is recommended The range of Step Amplitude is 0 01 0 25 V Chapter 5 Control Menu The compensation level is the percentage of resistance you want to compensate based on the measured solution resistance The range of this parameter is 0 200 The default value is 100 Overshoot level is the criterion of the stability test As the amount of positive feedback increases the system might become unstable Before the potentiostat start to oscillate the overshoot in current response to the potential pulse will appear The higher the allowed overshoot level the higher the possible compensation level but the worse the system stability The range of this parameter is 0 100 The default level is 2 If you click the iR Test button the system will engage solution resistance and stability test The result will be reported in the iR Comp Test Results Box For more details about the iR compensation please see Intelligent Automatic Compensation of Solution Resistance P He and L R Faulkner Anal Chem 58 517 523 1986 iR Compensation for Next Run When this box is checked the iR c
160. onstant potential or open circuit 4 26 Chapter 4 Setup Menu Notes 1 The experimental sequence follows cleaning first pulse and second pulse This sequence will be repeated until the total number of cycles is reached or interrupted by user There is no data acquisition during cleaning step If the cleaning time is zero this step will be ignored Data are sampled for first and second pulses and the difference is reported 2 The data is sampled at later 4 period of pulse 1 and 2 The longer the pulse width the longer the sample interval Long sample interval will have better signal averaging and less noise 3 During experiment whenever the data exceed the maximum allowed points the data storage interval will be doubled automatically Therefore data points will not overflow for an unexpected long experiment 4 When 1 current scale is displayed during run it will automatically fit the data in scale When 2 current scales are displayed during run they is 1 100 and 1 10 of full scale When 3 current scales are displayed during run they is 1 100 1 10 and 1 1 of full scale 4 27 Chapter 4 Setup Menu Parameters for Double Differential Pulse Amperometry In Double Differential Pulse Amperometry DDPA it combines two sets of the differential pulse amperometry Two sets of data will be recorded and displayed Each set consists of a cleaning potential without current sampling and two pulsed potential with current sampling
161. ontrolled independently When X Y axis freeze is not checked the X Y scale will have the value that was used in the present plot Sometimes the XY axis can not be frozen at the exact scale you entered in order to have an integer number of ticks on the X Y axis XY Title For each electrochemical technique the system provides default X Y axis titles If you want to customize them check the items and enter the title you want to appear Unit You can enter the unit or dimension of customized XY axis titles XY scale You can change the size of the plot by changing the XY scale The default XY scale is 1 that is full size This is particularly useful when you want to print the plot for publication or when you want to paste the plot into a word processor Data You can choose the data set to be plotted Depending on the technique the selection varies See the Present Data Plot command description Cursor Lock to Data Points The cursor could be either locked to data points or free of movement Current Density If this item is checked the current density will be displayed Electrode Area The electrode area is used to calculate the current density E vs Reference Electrode By default the potential axis title is Potential V If this item is checked the type of reference electrode used in the experiment will be attached to the potential axis title For instance the potential axis title might be Potential V vs SCE You ca
162. onvenient and faster than using mouse click and drag 6 The internal noise of the instrument is quite low The most common and most serious noise source is the line frequency 60 Hz or 50 Hz There are analog low pass filters to reduce noises At a scan rate of 0 1 V s the automatic filter cutoff setting is at 150 or 320 Hz The line frequency will pass and noise appears At a scan rate of 0 05 V s the cutoff frequency of the filter is 15 or 32 Hz The line frequency noise can be effectively reduced The line frequency noise can be reduced if the sample interval is set at multiples of the period of power lines For small signals and relatively fast experiments faraday cage is strongly recommended 7 To display data in different ways use the Graph Options command under the Graphics menu Check Page 6 1 of this manual for available data display formats 2 7 Chapter 2 Getting Started Installing USB driver under Windows If you have the serial port we suggest you not to worry about the USB The USB is really a USB Serial adapter It is a true USB but it converts the USB to serial port by using the USB driver software provided by the USB chip vendor It is therefore provide no specific advantages over the serial port The reason we put it there is because some computers such as notebook computers may not have the serial port On the other hand the USB serial port driver software may not be perfect We tried all the computers that has
163. or instrument test Cell On Between Runs By default the cell will be turned on during run and turned off after run Check this will make the cell connected after run Caution should be take when this item is checked Connect or disconnect the cell in an improper sequence could damage the electrodes when the cell is on It is recommended to connect the reference and counter electrodes first When disconnect disconnect the working electrode first Return to Initial E after Run Check this will let the potential return to the Initial E after run Otherwise the potential will remain at the end value of the previous run This will make sense only if Cell On Between Runs is checked This command has a toolbar button Chapter 5 Control Menu Step Functions Command Use this command to generate a contineous square waveform This command can be used for electrode conditioning or cleaning or other purposes No data will be collected and displayed The system displays the Step Functions dialog box so you can set the step conditions and run the step function generator Step Functions J Stat E Maan tc Duration s fo StepE1M i1 A 0 Step Time 1 s for StepE2 V i2 a 0 Step Time 2 s for Step Segment 20 l Galvanostatic Mode Ix OK Cancel Help tle The following options allow you to set set the step potentials duration and segments Param Range
164. or operation Override Present Data When this box is checked the currently active data will be replaced by the mathematically operated data Otherwise the mathematically operated data will be displayed but will not override the currently active data In this case when the Present Data Plot command under the Graphics menu is invoked the original data reappears Chapter 7 Data Processing Menu Fourier Spectrum Command Use this command to obtain the Fourier spectrum of the currently active data This command presents a Fourier Spectrum dialog box Fourier Spectrum E xj x Scale Y Scale C nth com x Linear Cancel C Logrithmic Help M Override Present Data To calculate a Fourier spectrum click the OK button The following options allow you to select the parameters to calculate a Fourier spectrum X Scale The X data array of the Fourier spectrum can just be the nth component a 1 s scale or a 1 V scale An nth component scale is generally used It is available for all techniques Its physical meaning comes from experimental parameters The 1 s and 1 V scales have a clear physical meaning For time based experiments the 1 s scale should be used and the 1 V is invalid for voltammetric experiments the 1 V should be used since the 1 s scale may not be valid Cyclic Voltammetry and Linear Sweep Voltammetry are special both 1 s and 1 V scales can be used Y Scale The Y data array is the Fourier coeffi
165. ord the error message and contact CHI for service no current response electrode leads is not connected or broken leads noisy data unreliable data transfer If the data reading exceeds 10 x sensitivity scale the problem could be due to comm port Make sure the network is disconnected Try another computer reference electrode check if air bubble is impedance too high trapped at the reference electrode tip change to reference electrode with vicor tip DO Windows application error electrically noisy use Faraday cage also see environment chapter 2 Useful Tips instability of potentiostat use Cell command under A 4 Appendix due to large double layer Control menu to manually capacitance set the stabilizing capacitor on aes is too weak use the highest sensitivity a ne as possible set filter computer problem make sure no network card or fax modem card in the computer system If there is one unplug it and try again If the problem persists try a few more computers sensitivity scale is too fee eee lower the sensitivity scale range areas problem use Hardware Test command under Setup menu to test the hardware the experiment Y axis title rotate in a printer driver use Font command under wrong angle incompatibility Graphics menu to toggle the Y axis title rotation unreasonable default different version of delete old cfg file a new conditions software and the configure configure file will be generated a
166. ormat X Y comma X Y TAB X Y space X Y linefeed 3 7 Chapter 3 File Menu This allows you to make the data format compatible with other commercial software such as spread sheet and data base handlers Number of Significant Figures It allows you to control the data precision of the text file The default is 4 significant digits This is sufficient for most applications You can change the setting to a maximum 10 significant digits However more significant digits result larger data files Data Point Interval This allows you to store or display only a part of the data points It is helpful when examining data or to reduce file size However some details might be lost DigiSim Format for CV and LSV Data This is only for CV and LSV data When this box is checked the text data file will be readable directly by DigiSim Bioanalytical Systems West Lafayette IN Excel 3D Format This is only for SECM image data When this box is checked the output text data file will be readable directly by Excel Microsoft Corp Redmond WA to generate a 3D surface plot To generate Excel 3D surface plots follow these instructions 1 Start the Excel Program 2 Open the target text data file created by the CHI900 CHI900A CHI900B program 3 The Text Import Wizard Step 1 of 3 dialog box will appear Click Next 4 The Text Import Wizard Step 2 of 3 dialog box will appear Select Delimiters to match the data s
167. ostion Cancel I Stir During Deposition Help rl m Deposition Potential Initial E C Deposition E Deposition E W fo Deposition Time sec 15 The following options allow you to set stripping mode control Stripping Mode Enabled When this item is checked the stripping mode is enabled When it is enabled a deposition step will be inserted before quiescent time step while running experiment The deposition potential and time can be selected in this dialog box After deposition period and before quiescent time the potential will be set back to initial potential The potential scan during stripping step will start from initial potential Purge During Deposition When this item is checked the system will purge solution during deposition period Stir During Deposition When this item is checked the system will stir solution during deposition period Deposition Potential You can have a choice of using initial potential or some other potential as deposition potential by clicking one of the radio button If you choose not to use initial potential as deposition potential you have to enter the Deposition E as described below Deposition E Enter the deposition potential that is different from initial potential This value will have no effect if initial potential is chosen as deposition potential Deposition Time Enter the deposition time The parameter range is from 0 to 100000 Chapter 6 Graphics
168. per kinetic parameters If the overdetermined equilibrium constant involves a chemical reaction the backward rate constant will be determined by the system The forward constant must still be entered If an electron transfer process is involved the standard redox potential will be determined by the system The heterogeneous rate constant and the alpha coefficient must still be entered 9 5 Chapter 9 Simulation Menu Concentration and Diffusion Coefficients dialog box This dialog box allows you to enter the concentrations and diffusion coefficients Concentration and Diffusion Coefficients Reactions Species Conc M D om2 s OK Sis a i A 0 001 i e 005 Cancel ti aes B fi e 005 Help 4 D C B 1e 005 D i e 005 On the left side of the panel the reaction mechanism is listed This will remind you of each step The species involved in the reaction are also listed On the right side of the panel you can enter the concentrations and diffusion coefficient corresponding to each species 9 6 Chapter 9 Simulation Menu Surface Concentration dialog box This dialog box allows you to enter the surface concentrations Surface Concentration x Reactions Species Conc mol cm2 A e B A fle to Cee D Cancel A C B fo Help B D A D C B E D fo On the left side of the panel the reaction mechanism is listed This will remind you of each step The species involved in the reac
169. ph Option command Note This is the note text editor box Enter your note here The note is not displayed on the plot but will be saved in the data file It allows you to put more comments about the data and remind you later about the purpose and the conditions of the experiment Linear Curve Fitting Checking this box will allow the data to be fit linearly by the least square method A best fit straight line will also appear on the plot Chapter 6 Graphics Menu Peak Parameter Plot Command Use this command to plot the peak current versus scan rate peak current versus square root of the scan rate or peak potential versus the logarithm of the scan rate For a reversible surface reaction the peak current is proportional to the scan rate For a reversible diffusive system the peak current is proportional to the square root of the scan rate The peak potential should be independent to the scan rate for a reversible reaction A shift of peak potential as a function of scan rate indicates either slow kinetics or chemical complexity You can also do linear curve fitting of the data This command works only for cyclic voltammetric or linear sweep voltammetric data For CV data the system only searches for the currently active data segment After you set the potential window for peak and select the proper files click the OK button to display the plot The X Y plot is temporary and it disappears if other data display commands are invoked Howev
170. please try USB as the communication port If it still does not work please try other computers The instrument we delivered was burned in for a week and tested In most of the cases the Link Failed message is caused by the computer serial port problem Once the instrument and PC can communicate you can connect the electrode leads to the rear panel The clip with green cover is for the working electrode the white one is for the reference electrode and the red one is for the counter electrode The black one is a sensing electrode Please check the Appendix of this User s Manual for description of 4 electrode configuration and the sensing electrode usage Connect the electrode leads to the rear panel The clip with green cover is for the working electrode the white one is for the reference electrode and the red one is for the counter electrode The Cell Control on the rear panel can be used to control purge stir and mercury drop dislodge Please see the Appendix for more information If you have a Pine rotating disk electrode RDE it is possible for the instrument to control the RDE with the instrument Model 430A 440A only Two banana jacks on the rear panel will provide a voltage of 0 10 V corresponding to a rotation rate of 0 10 000 rpm Running EQCM The CHI400A series EQCM contains a potentiostat galvanostat CHI440A an external box with oscillator circuitry and the EQCM cell see Figure 2 2 To do EQCM please check the
171. plots if available For linear sweep voltammetry LSV the special plot is the Polarization Resistance Plot After this command is invoked the program will check the potential at zero current If it is found it will be used as E V I 0 Otherwise a warning Potential at zero current not found will be issued A Polarization Resistance Plot dialog box will appear Polarization Resistance Plot m Potential Window E V i O i Cancel Window VJ fo 03 Hel Help After entering the center potential and the potential range click OK and a polarization resistance plot will be constructed Polarization resistance and correlation will be reported The polarization resistance plot is temporary and disappears if other data display commands are invoked However you can use Graph Option Color and Legend and Font commands to customize your plot Chapter 6 Graphics Menu Graph Options Command Use this command to select graphic plot options The graphic options allow you to selectively turn on or off the plot captions XY grid and XY axis inversion You can also freeze the XY axis customize the XY axis titles and write memos that can be saved together with the data Most of the parameters will be saved when you end the program and reloaded when you restart the program This command presents a Graph Options dialog box Graph Options Screen Printer Grid and Inv v m 4 a 4 A Iv X Grid Cancel
172. potential increment The instrument will also automatically re zero both potential and current to compensate the hardware drift due to temperature and time Therefore periodic recalibration of the instrument can be avoided The model 400A is the redesign of the model 400 series The model 400A series uses FLASH memory to store the control program inside the instrument We can update software through e mail This is more convenient than old design that uses EPROM We need to mail the EPROM for software update The 400A series has a serial port default and a USB for data communication with the PC You can select either serial port or USB by changing the jumper setting on the board However you can use only one of them A 16 bit highly stable bias circuitry is added for current or potential bias This allows wider dynamic range is ac measurements It can also be used for re zero the dc current output An auxiliary multi channel high resolution data acquisition system 20 bit 1000Hz and 24 bit 10Hz is added to allow external voltage signal such as spectroscopy signals to be recorded together with the electrochemical data The instrument is controlled by an external PC under Windows environment It is easy to install and use The user interface follows Windows application design guide If you are familiar with Windows application you can use the software even without operation manual or on line help The commands parameters and options are in
173. ption Init E V 10 10 Initial potential Final E V 10 10 Final potential Incr E V 0 001 0 05 Increment potential of each point Amplitude V 0 001 0 5 Potential pulse amplitude 1st Pulse Width sec 0 01 10 First potential pulse width 2nd Pulse Width sec 0 01 10 Second potential pulse width Sampling Width sec 0 001 5 Data sampling width Pulse Period sec 0 05 50 Potential pulse period or dropping time Quiet Time sec 0 100000 Quiescent time before potential scan Sensitivity A V le 12 0 1 Sensitivity scale Open Circuit at Initial E Check or Step 1 could be either held at a constant uncheck potential or open circuit Notes 1 Init E and Final E should be at least 0 01 V apart 4 17 Chapter 4 Setup Menu 2 In Differential Normal Pulse Voltammetry the potential of first step is normally held at Initial E where no electrochemical reaction will occur The second step is incremented every cycle A current sample is taken at the later part of the period The potential of the third is also incremented like the second step but it is more positive for positive scan or more negative for negative scan than the second potential by a constant magnitude amplitude The second sample is taken at the later part of the period The difference between the two current samples is reported as the function of the second potential 3 Pulse Width should be no more than half of Pulse Period otherwise the syste
174. quartz crystal using measured frequency change Af Sauerbrey equation where fo is the resonant frequency of the fundamental mode of the crystal A the area of 2 Zl Ay HP the gold disk coated onto the crystal 0 205 cm for given crystal p the density of the crystal and u the shear modulus of quartz The density of the crystal is 2 648 g cm and the shear modulus m is 2 947 x 10 g cm s For 8 MHz crystal the mass change is 0 14 ng for 0 1 Hz frequency change Af I Cell Bod Computer Cell Bottom Figure 2 2 EQCM setup When the cell is just connected you will see significant frequency drift This is normal It usually takes hours to reach the thermal equilibrium The drift can also occur as the room temperature changes It is recommended to have the oscillator box connected and leave the instrument power on all times It will reduce the equilibrium time when you change the crystal Other factors that can cause drift and noise include vibration contact and line frequency interference You may want to put the EQCM cell on a solid desk top 2 4 Chapter 2 Getting Started to avoid vibration and in a Faraday cage to reduce both electrical noise and frequency noise due to environmental interference You may also cover the holes on the cell top to avoid air flow Try to locate the gold electrode disk to the center of the cell The cell is designed to allow manually adjust the disk position slightly
175. rerun drop is set at 0 the same drop used in the previous experiment will be used for the next experiment More than one prerun drops might be useful if the SMDE occasionally traps little air bubble in the capillary and loses contact This option can also be varied from Cell command under Control menu Abort Experiment at Level Experiment will be terminated automatically if the current or charge level reaches the specified value or overflow It allows electrode over current protection If No is selected experiment will end normally Current Display during Quiet Time You can display current during quiet time either numerically or graphically The sensitivity scale will be switched automatically in order to read current properly If No is selected current will not be displayed and the sensitivity will be the same as what used in the experiment Abort Quiet Time Quiet time before data acquisition will be terminated automatically if the current or charge level reaches the specified value or overflow If No is selected experiment will end normally 5 5 Chapter 5 Control Menu Repetitive Runs Command Use this command to run a series of experiments During repetitive runs the instrument will check the data link If link fails the command is terminated and an error message will appear The system will also check the combination of experimental parameters If illegal combination is encountered the command is terminated and an error
176. rger interval lowers your data point density This is useful when you use Overlay Plots and different legends Default Pressing this button will reset all the colors and legends to the system default This command has a toolbar button 6 22 Chapter 6 Graphics Menu Font Command Use this command to select the font of the text used in the plot You can define the font the style the size and the color You can also rotate the Y axis title for printing The font will be saved when you exit the program and will be reloaded when you restart the program This command presents a Font Selection dialog box Font Selection iTems Font Style Size Color OK Axis Label Avis Narrow Regua E H Change Cancel Avis Tite Times New Roman Bold fic chance Help Header fail Bod fiz Change Default Parameter ia Regar Change Monochrome Results ia Regua Change Bold Change H ieie kali Courier New Numerical Y axis Title Rotation on Printer 270 degree nm To change the font style size or color of the text press the Change button of the corresponding item The Y axis title should go from bottom to top However different printers define the character rotation angles differently For instance HP LaserJet IV defines the desired rotation as 90 degrees but IBM Lexmark 4039 12R defines it as 270 degrees If you find that the Y axis title goes from top to bottom change the selection u
177. row switch or a contact pin block wire jumpers are used for setting soldered in to 6 pin holes two rows and three columns The default switch setting is at the left position for RS 232 serial port selection If you change the setting by switching to the right position the selection is the USB port 2 2 Chapter 2 Getting Started In the later portion of this chapter the USB software installation is described in detail If you consistently get Link Failed message try other computers The instrument we delivered was turned on for a week and tested Nearly in all the cases the Link Failed message is caused by the computer serial port problem The unreliable data communication could be due to some background tasks that generate interrupt The serial port data communication is based on interrupt For some reason Microsoft Windows makes the priority of interrupt for serial port lower and lower Other devices such as disk access screen saver virus scan internet connection etc will all generate interrupt that could interfere with the serial port data communication Please turn off the screen saver disconnect internet connection disable virus scan program and try again You should also not use network card Network will generate background interrupt that interfere with the data transfer between the PC and the instrument You should disconnect the connector to the network card If you get Link Failed message after all the efforts
178. rrection Command ssessesseesseesseseesseesreserssessesnessseesesressee 7 9 Data Point Removing Command ss ssessessseseosseeseeseesseesresrssseesesresseessessressessessees 7 10 Data Point Modifying Command ccceecccesceesseesseceeceeeeeeseecssecnseeneeeenseeenaees 7 11 Bkgnd Subtraction Command ssssseseeeseeseesseesseseeesoesseseesseessessrssressessrsseessessressee 7 12 Signal Averaging Command s ssessesessseessesseseessessresressteseeseesseesesresseesseseessesse 7 13 Mathematical Operation Command 0 cccecceecceesceesceceseceteeeeeeesseecaeenseeeneenees 7 14 Fourier Spectrum Command isis esis ccacassicevassasaendassesdeonseceeeeaatineatacveecdesseeaceadinnss 7 15 Chapter 8 Analysis Menu Calibration Curve Command s ssesseesseeseseessessesresseestesresseesesresseesseserssressessessees 8 1 Standard Addition Command s ssseseeseeseesesseseesseessessessseestesresseeseesresseesseseesseesse 8 3 Data File Report Command sco astacdie arts ett scvnate tare sae inca enna ae 8 5 Time Dependence Command 552 ceciane seed esos lea iaiusecsetianeuhneeleiiee sa yesxasaesce 8 7 Special Analysis Command aig coher s0 ae sssagna Pic tetta pales seats eeqnchenreasen bie lar geremeneee 8 9 Chapter 9 Simulation Menu Mechanism Command sce cecchastssaact sorece ccc uaic chem dcecsantunccansuan eepaatuncaatemaecsoataneets 9 1 Potentials and Rate Constants dialog DOX eeecceccceeeteceeeeeeeeeeteeeeeeeaeees 9 5 C
179. s 1 100 1 10 and 1 1 of full scale 5 To display data for 1st 2nd DPA or both use the Graph Option command under the Graphics menu to choose data display options 4 29 Chapter 4 Setup Menu Parameters for Triple Pulse Amperometry In Triple Pulse Amperometry TPA three potential pulses are applied First two pulses are for electrode conditioning or cleaning The current is sampled at the end of the third potential pulse The current is recorded as the function of time The third potential pulse could be at a constant potential or be incremented after each cycle The following diagram shows the potential waveform applied as the function of time and the current sampling scheme Data Sampling kK El Potential V Time s The following are the experimental parameters their range and descriptions Parameters Range Description E1 V 10 10 First pulse potential Duration 1 sec 0 32 First pulse duration Open Circuit Check or Step 1 could be either held at a Uncheck constant potential or open circuit E2 V 10 10 Second pulse potential Duration 2 sec 0 32 Second pulse duration E3 V 10 10 Third pulse potential Duration 3 sec 1 32 Third pulse duration Incr E V 0 0 2 Increment potential Init E V 10 10 Initial potential during quiescent time Final E V 10 10 Final potential for scan 4 30 Chapter 4 Setup Menu Number of Cycles 10 100000 Number of Repetitive
180. s entering the instrument If chemicals do enter the unit then it should be switched off immediately and the nearest dealer CH Instruments Inc contact details at the front of this manual contacted Routine cleaning of the chassis of the instrument is not necessary A spill onto the outer casing that does not enter the instrument should be wiped off with a dry cloth making sure to wide away from any instrument connections Likewise the PC used to operate the instrument should be protected from the possible exposure to chemicals 2 c Despite the customers best efforts corrosion of the electrode leads can occur This condition is best diagnosed by running a CV from 1 V to 1 V ona 1 M Ohm resistor sensitivity set at 1 e 6 An Ohmic plot through the origin should be obtained with maximum currents of 1 uA Working contacts green and black are connected to one side of the resistor and counter aux and reference red and white to the other Noticeable divergence from this behaviour i e linearity through origin may suggest faulty leads 2 d Erroneous data behaviour in an actual electrochemical experiment may be due to factors such a faulty cell connections poor reference electrode contact or poor condition of the working electrode Reference and working electrodes are consumable items and are freely available from CH Instruments Inc or your local dealer see Appendix for a description of the range of accessories available Where a customer
181. s for products returned to outside of the United States Warranty service does not include repair of failures caused by misuse accident modification unsuitable physical or operating environment improper maintenance and service of the product by unauthorized personnel In no event shall CH Instruments be liable or in any way responsible for any lost profits lost savings incidental damage or other economic consequential damages This is true even if you advise CHI of the possibility of such damages Appendix Safety Section 1 LVD Notes for manual Safety issues and protection of instrument against damage 1 The unit described in this manual is designed to be operated by trained personnel with some reasonable background knowledge of electrochemistry Any adjustments maintenance or repair must be carried out as defined by this manual please refer to appendix sections and by a person qualified and aware of the hazards involved 2 a It is essential that operating personnel employ a safe system of work in addition to the detailed instructions specified in this manual 2 b The instrument should be placed in a position where the likelihood of the ingress of a chemical spill is kept to an absolute minimum Efforts should also be made to avoid contact of the instrument with for instance corrosive vapours The electrochemical cell should not be placed on top of the unit due to the risk of leakage and the possibility of the cell content
182. save simulation parameters read simulation parameters real time data display real time display of concentration profiles dimensionless current equilibrium data automatic search and determine over determined equilibrium constants View e data information date time filename data source instrument model data processing performed header and notes e data listing data information and numerical data array 1 7 Chapter 1 General Information e equations general equations and equations relating to various electrochemical techniques e clock e toolbar e status bar Help e context sensitive help e index e using help about the application 1 8 Chapter 1 General Information System requirements Operating System PC with Microsoft Windows 95 98 NT Me 2000 XP Communication between PC and instrument RS 232 serial port or USB port Output device any printer or plotter supported by Windows Hardware Specifications Potentiostat Galvanostat Model 440A only Potential 10 V Current 250 mA Compliance Voltage 12 V Potentiostat rise time lt 2 us Four Electrode Configuration Input Impedance of Reference Electrode 10 Q Minimum Potential Increment in Sweep Techniques 100 uV Potential Update Rate 1 MHz Maximum Sampling Rate 200 kHz 16 bit Current Measurement Range 1x10 0 1 A V in 34 ranges Low Current Measurability below 50 pA Automatic Re zeroing both potential and current again
183. sec 0 01 50 Quiet Time sec 0 100000 Sensitivity A V le 12 0 1 Notes Description Initial potential Final potential Increment potential of each point Potential pulse width Data sampling width Potential pulse period or dropping time Quiescent time before potential scan Sensitivity scale 1 Init E and Final E should be at least 0 01 V apart 2 Pulse Width should be no more than half of Pulse Period otherwise the system will automatically readjust Pulse Width 3 Sampling Width should be no more than half of Pulse Width otherwise the system will automatically readjust Sampling Width 4 16 Chapter 4 Setup Menu Parameters for Differential Normal Pulse Voltammetry In Differential Normal Pulse Voltammetry DNPV the base potential is held at Init E A sequence of dual potential pulses are applied The first pulse will increment its magnitude for each pulse The second pulse has the constant amplitude The current at the end of two potential pulses are sampled The difference of these two current is recoded as the function of the first pulsed potential The following diagram shows the potential waveform applied as the function of time and the current sampling scheme Pulse Width Pulse Width J k Ak x Amplitude K A k AKA Pulse Period Sample Width Potential V Init E Time s The following are the experimental parameters their range and descriptions Parameters Range Descri
184. sos gates ce Sloe vay mans a iaaea iae i iiiaae 5 2 Rum Status Command lec ences ote accauenuiaeidertyaresceeeay oanieaew 5 3 Repetitive Runs Command fea cee cass creecsicadetes cesuagecheuaee oases a Mee etaer aca oaematae 5 6 Multiplexer Command scescccece exis cumin annie io dues 5 8 M cro Cri aT aiarra Soc sas den aad bas laa aR aE AE E AA RARA 5 11 Open Circuit Potential Command 2q sscccstiniseii neha acctantee nieslus acces 5 14 iR Compensation Command scpces sacks censdandngaemdratealencsatasseadantod edaeaseaenees 5 15 Filter Setting Command UA RP Rr MARA nee PEON RRO BRN Wea re PRR CRED Ratio Beans rR ER IESE Are 5 17 CellsConimand jos ses cette Siete cdots ati Aenea ae BAe ARS 5 19 Step Functions Command Nene ate Sernecaier mmr REE air on Ser ang mnrRRE HUE St SOY st pert erate feet 5 22 Preconditioning Command 45 scc2er sss t vastus aeteeca etc sunt nests suber atetanasanetswiuiass 5 24 Rotating Disk Electrode Command se 20 32 5 5 ssissvesascs tevadastinsatigsaesdeasdataesasdanteg ts 5 25 Stripping Mode Command 52 93 isscty shes ceagescdetteacte eateanccasteanleriuaateceesdentedaaionicaes 5 26 Chapter 6 Graphics Menu Present Data Plot Command is cis nics sicts eeiets aa kaduee weavieeds east eauatewey 6 1 Overlay Plots Command o c 5sccuvn cr ccunsadageantcaesedea cecueeadageas oe neuuasiuarceuadeucauneen as 6 5 Add Data to Overlay Command 000 ccccecccesccessceescecesecesecseceeescecaaeceseeseneeseneenaees 6 6 Parallel Plo
185. ssing performed If several types of data processing have been executed multiple item will be checked This reminds you what you have done to this set of data in the past 10 1 Chapter 10 View Menu Header This box displays the header The header can appear on the data plot Note This box displays the note about the experiment The note can remind you about the purpose and the conditions of the experiment 10 2 Chapter 10 View Menu Data Listing Command Use this command to list the experimental conditions results and numerical value of the currently active data The format of the listing can be altered by the Text File Format command under the File menu The system displays the Data List dialog box so you can view the numerical data Use scroll bar to view the listing if necessary If the listing is too long the later part of the data will be truncated Aug 10 1994 14 11 32 Cyclic Yoltammetry File cv1 bin Data Source Experiment Instrument Model CHIO Data Proc Smoothing Header 0 5 mM Fetrocene in 0 1M LiCIO4 CH3CN 2mm Pt disk Note Init E V 0 1 High E 0 7 Low E M 0 1 Init P N P Scan Rate Vs 10 Segment 2 Sample Interval 0 001 Quiet Time sec 2 Sensitivity A V 1e 4 Segment 1 Ep 0 439 ip 3 622e 54 Sh 2 961e 7C Segment 2 Ep 0 326V ip 3 235e 54 h 2 526e 7C Potential Current 4 10 3 Chapter 10 View Menu
186. st drift Cell Control purge stir and knock RDE Rotation Rate Control 0 10V voltage output for 0 10000 rpm Instrument Dimension 12 5 width x 11 depth x 4 75 height Weight 12 lb Chapter 10 View Menu Data Information Command Use this command to view the information of the currently active data This command presents a Data Information dialog box Data Information Data Proc Performed Filename Source JExperiment 1st Derivative 2nd Derivative Model cHio 3rd Derivative 4th Derivative 5th Derivative Integration Semi Derivative Semi Integral Interpolation Baseline Correction Data Point Removing Data Point Modifying Bkgnd Subtraction Signal Averaging x Math Operation Y Math Operation Date 10 Aug 1994 Time Header 10 5 mM Ferrocene in 0 1M LICIO4 CH3CN 2mm Pt disk Note The following items allow you to view the information of the currently active data Filename This non editable box displays the filename of the currently active data If it has not been stored the filename is Unsaved Data Source This box displays the data source that is either experimental or simulated Model This box displays which instrument model was used when the data was acquired Date This box displays the date that the data was acquired Time This box displays the time that the data was acquired Data Proc Performed This list box displays the type of data proce
187. stat You should check the connection or you may ignore the warning Disable this option will reduce the time delay before actual running of experiments Use Open Circuit E as Init E 5 3 Chapter 5 Control Menu When this box is checked the system will test open circuit potential before running the experiment and use the open circuit potential as initial potential External Trigger Run When this box is checked Run will be initiated by the external trigger signal from the Cell Control port on the rear panel See appendix for the pin assignment iR Comp for Next Run When this box is checked the iR compensation for next run is enabled You may not be able to enable iR compensation if the automatic compensation is set and the iR compensation test is not conducted or the sensitivity scale is altered Certain techniques such as TAFEL BE IMP CP and PSA do not allow iR compensation This option can also be turned on or off from iR Compensation command under Control menu Smooth After Run When this box is checked the automatic smoothing after run is enabled Certain techniques such as TAFEL BE and IMP do not allow smoothing This option can also be turned on or off from Smoothing command under DataProc menu There are two types of digital smoothing available the least square and Fourier transform smoothing To set the mode of smoothing use Smoothing command under DataProc menu Purge Between Runs Check this item will allow purg
188. studies with the SECM have now been reported from a number of laboratories all over the world and the instrument has been used for a wide range of applications including studies of corrosion biological systems e g enzymes skin leaves membranes and liquid liquid interfaces Trapping and electrochemical detection of single molecules with the SECM has also been reported With the introduction of the CH Instruments SECM developed in collaboration with the University of Texas group this technique now becomes available to any laboratory 1 A J Bard F R F Fan J Kwak and O Lev Anal Chem 61 132 1989 U S Patent No 5 202 004 April 13 1993 2 A J Bard F R Fan M V Mirkin in Electroanalytical Chemistry A J Bard Ed Marcel Dekker New York 1994 Vol 18 pp 243 373 CHI900B 910B SECM Specifications Micropositioner X Y Z resolution 1 6 nm combination of Stepper motors and Piezos CHI910B has a closed loop Piezo controller X Y Z total distance 2 5 cm or 5 0 cm Bipotentiostat Probe Potential 10V Substrate Potential 10V Compliance Voltage 12V Current Sensitivity 10 A V to 107 A V Maximum Current 10mA Fast A D Converter 16 bit 25 K Hz ADC Resolution 20 bit 1kHz 24 bit 10 Hz Type of Measurements SECM Imaging Probe Scan and Approach Curves Surface Patterned Conditioning CV CA DPV SWV i t DPA DDPA TPA BE SSF STEP CP CPCR ISTEP and E t SECM Image
189. such as Concentration or Peak Current to be plotted Conc Unit Enter the concentration unit or dimension such as ppm or M Report Name Enter the report filename if you want to save the time dependence report text file If the name already exists an override warning will be issued If no filename is specified the report will be shown but not saved Report Data Type You can report concentration or peak current Header This is the header text editor box Enter your header here To display the header on top of the plot check the Header box using the Graph Option command Note This is the note text editor box Enter your note here The note will be saved in the data file It allows you to put more comments about the data and remind you later about the purpose and the conditions of the experiment Read Use this command to read the data you saved Save Use this command to save your data XY titles units header and note will be saved along with the data Report Use this command to generate the time dependence report Plot Use this command to generate the time dependence plot 8 8 Chapter 8 Analysis Menu Special Analysis Command Currently this command is only active for TAFEL measurements You can use this command to calculate the corrosion rate from the Tafel experiment results If you have the TAFEL data available invoking this command will display the Corrosion rate Calculation dialog box Corrosion Rate Calculation a Exi D
190. t down to picoamperes Besides the commonly used cyclic voltammetry amperometric i t measurements many other electrochemical techniques are available All eight channels work for various electrochemical techniques except open circuit potential measurements The parameters for all the channels should be set before running experiments You can not alter the parameter setting during experiments During run you can alter display mode between single data set display and multi set data display either parallel or overlay plots After run you can choose data sets of any channels as parallel plots or overlay plots Techniques for the Model 1000 Series Multi Potentiostat pS Ce OS ee Corresponding polarographic mode can be performed amp Corresponding stripping mode can be performed Specifications 8 Channel potentiostat CV and LSV scan rate 0 000001 to 5 V s Potential range primary channel 3 275 V CA and CC pulse width 0 01 to 1000 s Potential range channel 2 8 2 0 V CA and CC Steps 320 Compliance voltage 12 V DPV and NPV pulse width 0 005 to 10 s Current range each channel 10mA SWV frequency 1 to 250 Hz Reference electrode input impedance IX10 ohm Current low pass filters Sensitivity scale Ix 10 0 001 A V in 7 ranges Potential and current analog output Input bias current lt 50 pA Cell control purge stir knock Current measurement resolution lt 5 pA Maximum data length 128000 points e
191. t reported during the simulation 9 9 Chapter 9 Simulation Menu Simulate Command Use this command to perform the digital simulation Set the mechanism the concentrations the kinetic parameters and the experimental parameters before you click this command In order to perform a simulation connect the instrument to the computer and turn it on The hardware only needs be tested once after you start the program You can copy the screen graphics to the clipboard during the simulation The user input mechanism will work only for high end instrument models Chapter 9 Simulation Menu AC Impedance Simulator and Fitting Program An impedance simulator is integrated into the software To use the impedance simulator you need to set the Technique to AC Impedance IMP and then use the Mechanism command to enter the equivalent circuitry Once the Mechanism command is invoked the original toolbar will be replaced by a new one The new toolbar contains symbols of components and commands The following screenshot shows the toolbar and the mechanism edit field s ec Imp0 bin sh C File Setup Control Graphics DataProc Analysis Sim View Window Help 18 x Ol Ro ele ele law ab om fe oe Si Fit Ret 558 6 W 4 149e 005 Here is the explanation of the toolbar buttons k Bau Undo je Redo Ro Rearrange the components Move components left right up and down eee Clear all the components in the edit fi
192. ta analysis for steady state responses One can also convert a diffusive or peak shaped response by semi integral or full integral to a sygmoidal curve and display a semilog plot For a reversible reaction the intercept on the potential axis is the half wave potential and the slope should be 0 059 n V Any discrepancy from the expected slope indicates slow kinetics or complexity of the electrode reaction You can also do linear curve fitting to the data After you set the options click the OK button to display the plot The X Y plot is temporary and disappears if other data display commands are invoked However you can use Graph Option Color and Legend and Font commands to customize your plot The system displays the Current Potential Semilog Plot dialog box Current Potential Semilog Plot m Potential Window f E From J 0 39 Cancel ETEME ES 0 45 Help M Linear Curve Fitting The following options allow you to set the plot parameters Potential Window Enter the potential window for the data to be plotted The potential window should be around the half wave potential and within 0 059 n V Data points ouside the specified potential window will be ignored Linear Curve Fitting Checking this box will allow the data to be fit linearly by the least square method A best fit straight line will also appear on the plot Chapter 6 Graphics Menu Special Plot Command Use this command to display special
193. ter Electrode for EQCM Cell CHI101 2 mm dia Gold Working Electrode CHI101P 2 mm dia Gold Working Electrode 3 pk CHI102 2 mm dia Platinum Working Electrode CHI102P_ 2 mm dia Platinum Working Electrode 3 pk CHI103 2 mm dia Silver Working Electrode Electrode Electrode CHILOSP 25 um dia Platinum Microelectrode 3 pk CHII 11 Ag AgCl Reference Electrode CHI111P Ag AgCl Reference Electrode 3 pk CHI112 Non Aqueous Ag Ag Reference 1 Electrode CHI112P Non Aqueous Ag Ag Reference 3 pk Electrode CHI115 Platinum Wire Counter Electrode CHI116 10 yum dia Platinum SECM Tip CHI116P 10 um dia Platinum SECM Tip 3 pk 4 CHII151 Mercury Mercurous Sulfate Reference ee peed CHI152 Alkaline Mercurous Oxide Reference 1 eal e Seaine CHI172 Electrode leads for a particular 1 CHI202 Faraday Cage CHI220 Simple Cell Stand CHI221 Cell Top including Pt wire counter electrode not a replacement part for the CHI200 cell stand CHI222 Glass Cell 1 CHI223 Teflon Cap 1 Notes 1 A Ag solution typical 10 mM should be prepared with the supporting electrolyte and AgNO not included This solution is then filled into the reference electrode compartment using a syringe not included The instructions will come with the components 2 The electrode polishing kit contains 1 bottle of 1 0 micron Alpha alumina powder 1 bottle of 0 3 micron Alpha alumina powder 3 bottles of 0 05 micron Gamma alumina
194. tion Concentration Peak Height OK pe a e E _Seve_ a Unknown 149 984 3 425e 007 Gael Addition 1 5 629e 007 2 2851 e 009 Help ion 10 999933 Addition 3 os3e 005 ovelation Read Addition 4 fo Save x Axis Title Concentration x Axis Unit ppb Y Axis Title Peak Current Y Axis Unit a Header Pb in water water Note ho Addtion2 200 7 961e 007 Slope po Calculate In standard addition the unknown is measured first and the peak height is recorded Then the standard solutions are added After each addition the peak height is measured again Usually the added volume is much smaller than the total volume in order to maintain the sample compositions and have the same matrix effect The increment concentration should be comparable to the unknown The following options allow you to enter the data for unknown concentration calculation or plotting Unknown Enter the unknown peak height for unknown concentration calculation Addition Enter the concentration and peak height current after adding the standard solution X Axis Title Enter the X axis title such as Concentration to be plotted X Axis Unit Enter the X Axis unit or dimension such as ppm or M to be plotted Y Axis Title Enter the Y axis title such as Peak Current to be plotted Y Axis Unit Enter the Y Axis unit or dimension such as A to be plotted Header This is the header text editor box Enter
195. tion ADC sample Uncheck interval is greater than 0 002 s QCM On if Sample Check or EQCM enable Interval gt 0 005s Uncheck Notes 1 The data sample interval should be chosen according to the length of the experiment The longer the experiment the larger the sample interval Long sample interval will have better signal averaging and less noise 4 24 Chapter 4 Setup Menu 2 During experiment whenever the data exceed the maximum allowed points the data storage interval will be doubled automatically Therefore data points will not overflow for an unexpected long experiment 3 Ifthe sample interval is greater than 0 005s it is possible to record external voltage signal such s spectroscopic signal simultaneously with the amperometric i t response Use the 9 pin D connector on the real panel for signal input Check the User s Manual for the pinout 4 Ifthe sample interval is greater than 0 002s High resolution ADC can be used to acquire data High resolution ADC usually provide better signal to noise ratio The data quality less depends on the sensitivity setting because of its higher resolution 5 When 1 current scale is displayed during run it will automatically fit the data in scale When 2 current scales are displayed during run they is 1 100 and 1 10 of full scale When 3 current scales are displayed during run they is 1 100 1 10 and 1 1 of full scale 4 25 Chapter 4 Setup Menu Parameters for Differential
196. tion are also listed On the right side of the panel you can enter the surface concentrations corresponding to each species 9 7 Chapter 9 Simulation Menu Concentration at Equilibrium dialog box This dialog box allows you to view the concentrations at the equilibrium Concentration at Equilibrium Ea Reactions Species Concentration F Aes a 476143005 Canal C e D TNT amp 5 B 1 981 oJ e 008 Help B D os 6 D 3 98555e 0 000952366 4 D C B On the left side of the panel the reaction mechanism is listed This will remind you of each step The species involved in the reaction are also listed On the right side of the panel the concentrations at equilibrium corresponding to each species are listed 9 8 Chapter 9 Simulation Menu Simulation Variables dialog box This dialog box allows you to change some simulation variables Simulation Yariables Temperature Deg C 25 a i Electrode Area em2 fi eet Capacitance uF jo Help Temperature Enter the temperature in Celsius here Both thermodynamic and kinetic parameters are a function of temperature Electrode Area Enter the area of the electrode in square centimeters here The current is proportional to the electrode area in planar diffusion situations or for surface reactions Capacitance Enter the electrode double layer capacitance in microfarads here Charging currents will be added to the total curren
197. tiostat CV and LSV scan rate 0 000001 to 10 V s Potential range 2 4 V CA and CC pulse width 0 001 to 1000 s Compliance voltage 7 5 V CA and CC Steps 1 320 Current range 2 mA DPV and NPV pulse width 0 001 to 10 s Reference electrode input impedance 1x10 ohm SWV frequency to 5000 Hz Sensitivity scale 1x10 0 01 A V in 7 ranges ACV frequency 0 1 to 2000 Hz Input bias current lt 100 pA Low pass filter for current measurements Current measurment resolution lt 5 pA Maximum data lene 128000 Data acquisition 16 bit 10 kHz Chassis dimension 7 W x 4 5 D x 1 A Differences of 1200A Series Models 1202A 1206A 1208A 1212A 1222A 1232A P Cyclic Voltammeny CV ts e e gt e Linear Sweep Voltammetry LSV e e e gt gt Chronoamperomety CA e CT T T e Chonocoulomeny CO e T T e Differential Pulse Voltammetry DPV J T e Normal Pulse Voltammetry NPV _ _ T gt gt Differential Normal Pulse Voltammetry DPNV T T Square Wave Voltammetry SWV J T T T SS AmperometricitCurve it d e gt J gt Differential Pulse Amperometry DPA Double Differential Pulse Amperometry DDPA Triple Pulse Amperometry TPA e E Sa Z T Te T Te C T Te e Open Cireuit Potential Time OCPT o o e _ a a re
198. to be plotted X Axis Unit Enter the X Axis unit or dimension such as ppm or M to be plotted Y Axis Title Enter the Y axis title such as Peak Current to be plotted Y Axis Unit Enter the signal unit or dimension such as A to be plotted Header This is the header text editor box Enter your header here To display the header on the top of the plot check the Header box using the Graph Option command Note 8 1 Chapter 8 Analysis Menu This is the note text editor box Enter your note here The note can not be displayed on the plot but will be saved in the data file It allows you to put more comments about the data and remind you later about the purpose and the conditions of this experiment Read Use this command to read the data you saved Save Use this command to save your data XY titles units header and note will be saved along with the data Calculate Use this command to calculate the slope intercept and correlation of the calibration curve If the unknown peak height is give the unknown concentration will also be calculated Plot Use this command to plot the calibration curve The plot will be automatically scaled according the data range To freeze the scale please use the Graph Option command 8 2 Chapter 8 Analysis Menu Standard Addition Command Use this command to calculate the unknown concentration by standard addition The system displays the Standard Addition dialog box Standard Addi
199. to the instrument The first time you make the connection the computer will prompt new USB device found and will automatically look for the driver and further install it Please wait until this process is completed 5 This USB device is really a USB Serial Port Converter Under the instrument software it treats this device as a serial port You need to find what port number is assigned to this device Please select Control Panel from your computer Start menu at the lower left corner gt Performance and Maintenance gt System gt Hardware gt Device Manager gt Ports COM amp LPT You will see the following information File Action View Help gt mea ga amp Disk drives vd Display adapters DVD CD ROM drives s Human Interface Devices E IDE ATA ATAPI controllers gy IEEE 1394 Bus host controllers py Infrared devices gt Keyboards B Mice and other pointing devices k Modems Monitors E Network adapters E 1394 Net Adapter E Intel R PRO 100 VE Network Connection E Intel R PRO Wireless LAN 2100 38 Mini PCI Adapter a PCMCIA adapters K CP2101 USB to UART Bridge Controller COM5 F ECP Printer Port LPT1 In this example USB is assigned to COMS This number may vary with different computers It may varies even with the same computer sometimes quite rarely You need to use the System command under the Setup menu to set the com port number In the future if
200. ts Command asensin a E a AAR E a 6 7 Add Data to Parallel Command os62ck cose ssiseteciats ecduuss neat ievibiees bin haalees 6 8 Zoom In COTTA 2 enoa hac cuakavsrcnis ales sham O ten teria A E i 6 9 Manual Result Command cso 0 ecco ss nig cess Cotvcsts ocd suvatavasusUotucvartachestavanaescucaseniote 6 10 Peak Definition Command 24 co ses in aout lees Lada Se ees 6 11 X Y Plot Commands ireen teat a A E A TA a A 6 12 Peak Parameter Plot Command 2 0 0 0 cceessseessessssssssssssssssssssssssssssssssnssssssaeaes 6 14 pemilog Plot Command sy onesie ia teva lecnae i aaa 6 16 Special Plot Command iriiritia eE R ECA E EERTE 6 17 Graph Option Command issen ieii a iai n aA 6 18 Color and Legend Command ssnssesnesseessesesseessessresrosseesresseesesersseessesrrssressesess 6 21 F nt Command eeren aee n a a a av las co nE A A EEs 6 23 Copy to Clipboard Command 42 3 cw nannies ata eee dad 6 24 Chapter 7 Data Processing Menu Smoothing Commands issar vices asi aa na AES E Te AAE R EAE denen 7 1 Derivatives Command eocturreiia a hea a a ana a a a 7 3 Int gration Command essesi iei r a ek alas hasnt tela 7 4 Semiinteg and Semideriv Command s ssssssessesseseeessesseesressessresessessteseesseesreseessee 7 5 Interpolation Command s sessseeseesessseessessessressesstsseesseeseesresstessesrsseessessessresseene 7 6 Baseline Fitting amp Subtraction Command 00 cceccceesceesceeeteceneceeeeeeseeeseeeenaeees 7 7 Linear Baseline Co
201. ts will be stored Large sweep segments might be useful for conditioning of electrodes 8 When scan rate is below 0 01 V s the sensitivity scale during run can be automatically switched according to the current level When it is activated the sensitivity selection will have no effect on the measurement However the automatic sensitivity switching range will be from le 8 0 1 A V instead of le 12 0 1 A V In order to select higher sensitivities automatic sensitivity switching option needs to be disabled 9 Scan Complete Cycles will only work for Sweep Segments at 3 5 7 9 odd numbers and if Initial E is different from High E and Low E When it works the last segment will stop at Initial E instead of High E or Low E 10 If the scan rate is lower than 0 5V s it is possible to record external voltage signal such s spectroscopic signal simultaneously with the voltammogram Use the 9 pin D connector on the real panel for signal input Check the User s Manual for the pin out and signal level requirements 11 When the noise level is high particularly line frequency noise lower resolution with signal averaging sample many times during the sample interval works better However if noise is not a problem high resolution ADC provide better accuracy and precision The data quality will be reasonable even the sensitivity scale is not optimized Chapter 4 Setup Menu 12 If the scan rate is less than 0 5 V s High resolution ADC ca
202. using the Stripping Mode command in Control Menu you have to uncheck the polarographic mode This command has a toolbar button Chapter 4 Setup Menu Parameters Command Use this command to set experimental parameters This command presents a Parameter dialog box so you can select the parameters you want to use Depending on the technique the parameters dialog box will be different The followings are the parameters for different techniques Parameters for Cyclic Voltammetry Parameters for Linear Sweep Voltammetry Parameters for Sampled Current Voltammetry Parameters for Tafel Plot Parameters for Chronoamperometry Parameters for Chronocoulometry Parameters for Differential Pulse Voltammetry Parameters for Normal Pulse Voltammetry Parameters for Differential Normal Pulse Voltammetry Parameters for Square Wave Voltammetry Parameters for A C Voltammetry Parameters for 2nd Harmonic A C Voltammetry Parameters for Amperometric i t Curve Parameters for Differential Pulse Amperometry Parameters for Double Differential Pulse Amperometry Parameters for Triple Pulse Amperometry Parameters for Bulk Electrolysis with Coulomtery Parameters for Hydrodynamic Modulation Voltammetry Parameters for Sweep Step Functions Parameters for Multi Potential Steps Parameters for Chronopotentiometry Parameters for Chronopotentiometry with Current Ramp Parameters for Potentiometric Stripping Analysis Parameters for Open Circuit Potential
203. utomatically simulation program does could not find the hardware connect and turn on the not run instrument user input mechanism is not try to use the predefined available to the instrument mechanism or you may have to give up Appendix Maintenance and Service The recommended operating temperature is 15 28 C Since the instrument is a sophisticated equipment you should not try to service it yourself If the instrument does not work properly please run the hardware test and contact the factory for service Limited Warranty This CH Instruments product is warranted against defects in workmanship and material If any failure resulting from a defect of workmanship or material shall occur under normal use within one year from the date of purchase as shown on the purchase receipt CH Instruments will at its option either repair the defective product without charge for parts and labor or provide a replacement in exchange for the defective product In order to obtain service under this warranty customer must notify CH Instruments before the expiration of the warranty period and make arrangements for the service Customer shall be responsible for packing and shipping the defective product with shipping charges prepaid CH Instruments shall pay for the return of the product to customer if the shipment is within the United States Customer shall be responsible for paying all shipping charges duties taxes and any other charge
204. wer on DB 25 connector provides power supplies and control lines see Cables and Connections in Appendix If DB 25 connector is not connected you can still do experiments as Picoamp Booster is disabled In this case the faraday cage is effective To purge inert gas you may unscrew one of the screws on the back of the faraday cage This will open a hole for inert gas tubing When the Picoamp Booster is connected and the sensitivity scale is at or below le 8 A V the Picoamp Booster will be enabled Otherwise it will be disabled The sensing of the Picoamp Booster existence and the enable disable switching are automatic Picoamp Booster will be disabled for techniques using automatic sensitivity switching such as TAFEL BE IMP IMP t and IMP E You do not need to disconnect it to run these techniques However for galvanostatic techniques such as CP CPCR and PSA Picoamp Booster has to be disconnected If the Picoamp Booster is not used please disconnect the DB 25 cable CHI684 Multiplexer CHI684 is a multi channel multiplexer for the model 400 400A 600A 600B 600C 700A 700B 700C 800B 900B and 1100A series The multiplexer switches four lines working sensing reference and counter in case of single potentiostat working 2nd working reference and counter in case of bipotentiostat You can have maximum 64 cells but only one cell can be connected at a time The multiplexer is controlled from the Mulrtiplexer command under the
205. ximum potential step range is 13 1 V 5 Shorter sample interval will increase data density but will reduce the signal noise ratio If earlier transient data is important shorter sample interval is recommended If the later part of data is of interest longer sample interval is recommended However minimum 100 points per step are required 6 Ifthe sample interval is less than 0 002s the data will not be transferred on the real time base Instead the data will be transferred after the experiment is completed Cell is turned off during the data transfer unless the Cell On between Run option is selected From start of experiment and data transfer there is a delay The total number of data points will be limited to 64K due to internal memory size limitation Sample interval might be automatically altered to adjust the data points in the reasonable range 7 Ifthe sample interval is longer than 0 002s data will be transferred during experiment Maximum 64K total data points are allowed for each step Sample interval might be automatically altered to adjust the data points in the reasonable range 8 Ifthe sample interval is greater than 0 005s it is possible to record external voltage signal such s spectroscopic signal simultaneously with the current Use the 9 pin D connector on the real panel for signal input Check the Appendix of the User s Manual for the pin out 4 12 Chapter 4 Setup Menu Parameters for Chronocoulometry In Chron
206. xperiment running time Sample Interval sec 0 0025 50 Sampling interval High E Limit V 10 10 High potential limit Low E Limit V 10 10 Low potential limit Notes 1 Ifhigh or low potential limit is reached a warning will be given 2 In general the data storage interval should be chosen according to the length of the experiment The longer the experiment the larger the data storage interval 4 46 Chapter 4 Setup Menu Parameters for Quartz Crystal Microbalance The system displays a Quarzt Crystal Microbalance Parameters dialog box Quratz Crystal Microbalance Parameters xj Run Time sec 400 Cancel Sample Interval sec for Help The following are the experimental parameters their range and descriptions Parameters Range Description Run Time sec 0 1 500000 Experiment running time Sample Interval sec 0 002 50 Data sampling interval Notes 1 During experiment whenever the data exceed the maximum allowed points the data storage interval will be doubled automatically Therefore data points will not overflow for an unexpected long experiment 4 47 Chapter 4 Setup Menu System Command Use this command to set up the serial communication port current polarity potential axis and current axis This command presents a System Setup dialog box System Setup E x m Communication Port C Com 2 Cancel C Com3 Help C Com4 m
207. you see Can not open comport error when you start the program please check Device Manager again and see what com port number is assigned If the com port number assignment is changed you need to set the com port number in the program accordingly If you do not see CP2101 icon under the Ports COM amp LPT please make sure if your instrument is turned on and the USB cable is connected properly 2 9 Chapter 3 File Menu Open Command Use this command to read an existing data file You can only open one data file at a time This will be the active data When the file is read it places data in the memory and the graphics are updated The technique and experimental parameters are also updated You can only open files generated by this or an older version of the software Since the software uses a multi document interface you can open multiple files by repeating this command This command presents an Open dialog box IMPE1 IMPE2 NPVO IMPE3 OCPT1 IMPE4 PSA0 gt File name evo Files of type Binary Data Files bin Cancel The following options allow you to specify the file to select File Name Type or select the filename This box lists files with the extension you select in the List Files of Type box You don t have to type the extension the system will automatically attach a bin extension to the filename List Files of Type Select the type of files you want to open Only
208. your header here To display the header on the top of the plot check the Header box using the Graph Option command 8 3 Chapter 8 Analysis Menu Note This is the note text editor box Enter your note here The note is not displayed on the screen but will be saved in the data file It allows you to put more comments about the data and remind you later about the purpose and the conditions of the experiment Read Use this command to read the data you saved Save Use this command to save your data XY titles units header and note will be saved along with the data Calculate Use this command to calculate the slope correlation of the standard addition curve The unknown concentration will also be calculated Plot Use this command to plot the standard addition curve The plot will be automatically scaled according to the data range To freeze the scale please use the Graph Option command 8 4 Chapter 8 Analysis Menu Data File Report Command Use this command to generate a report for stored data files The system presents the Data File Report dialog box Data File Report Species 1 Species 2 Species 3 Species 4 OK Species cu Pb Cancel Ep From J joz jos Ep To Y 0 35 0 52 Slope E23 223 Intercept 1 652e8 3825e9 0 Peak Shape Gausian Data Type Original gt Number of Species 20 Concentration Unit ppb Report Filename ewen x Read Save f Help feed

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