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ContentsPART 1 INTRODUCTION OF CS SERIES ELECTROCHEMICAL WORKSTATION................................................. - 1 -

PART 2 CS STUDIO SOFTWARE...................................................................................................................... - 5 -

1. INTRODUCTION.........................................................................................................................................- 5 -

1.1 ELECTROCHEMICAL TECHNIQUES................................................................................................................ - 5 -

1.2 SOFTWARE INSTALLATION......................................................................................................................... - 6 -

2. MENU........................................................................................................................................................- 8 -

2.1 FILE...................................................................................................................................................... - 8 -

2.2 SETUP...................................................................................................................................................- 8 -

3. EXPERIMENT SETTING............................................................................................................................ - 11 -

3.1 PSTAT/GSTAT(ECS)SETTING.................................................................................................................... - 11 -

3.2 CELL SETTING.......................................................................................................................................- 13 -

4. STABLE POLARIZATION............................................................................................................................ - 15 -

4.1 OPEN CIRCUIT POTENTIAL...................................................................................................................... - 15 -

4.2 POTENTIOSTATIC................................................................................................................................... - 16 -

4.3 GALVANOSTATIC.................................................................................................................................... - 18 -

4.4 POTENTIODYNAMIC............................................................................................................................... - 19 -

4.5 GALVANODYNAMIC................................................................................................................................- 21 -

4.6 POTENTIAL SWEEP-STEP.........................................................................................................................- 23 -

5. TRANSIENT POLARIZATION..................................................................................................................... - 25 -

5.1 MULTI-POTENTIAL STEPS........................................................................................................................- 25 -

5.2 MULTI-CURRENT STEPS..........................................................................................................................- 26 -

5.3 POTENTIAL STAIR-STEP(VSTEP).............................................................................................................. - 27 -

5.4 GALVANIC STAIR-STEP(ISTEP).................................................................................................................- 28 -

6. CHRONO TECHNIQUES............................................................................................................................- 29 -

6.1 CHRONOPOTENTIOMETRY....................................................................................................................... - 29 -

6.2 CHRONOAMPEROMETRY.........................................................................................................................- 30 -

6.3 CHRONOCOULOMETRY........................................................................................................................... - 32 -

7. VOLTAMMETRY....................................................................................................................................... - 33 -

7.1 CYCLIC VOLTAMMETRY........................................................................................................................... - 33 -

7.2 LINEAR SWEEP VOLTAMMETRY................................................................................................................ - 36 -

7.3 STAIRCASE VOLTAMMETRY...................................................................................................................... - 37 -

7.4 SQUAREWAVE VOLTAMMETRY................................................................................................................- 38 -

7.5 DIFFERENTIAL PULSE VOLTAMMETRY........................................................................................................ - 40 -

7.6 NORMAL PULSE VOLTAMMETRY.............................................................................................................. - 43 -

7.7 DIFFERENTIAL NORMAL PULSE VOLTAMMETRY........................................................................................... - 45 -

7.8 A.C. VOLTAMMETRY..............................................................................................................................- 47 -

7.9 2ND HARMONIC A.C. VOLTAMMETRY...................................................................................................... - 49 -

7.10 FOURIER TRANSFORM AC VOLTAMMETRY (FTACV)..................................................................................- 50 -

8. AMPEROMETRIC..................................................................................................................................... - 51 -

8.1 DIFFERENTIAL PULSE AMPEROMETRY (DPA)............................................................................................. - 51 -

8.2 DOUBLE DIFFERENTIAL PULSE AMPEROMETRY (DDPA)...............................................................................- 53 -

8.3 TRIPLE PULSE AMPEROMETRY (TPA)........................................................................................................- 54 -

8.4 INTEGRATED PULSE AMPEROMETRIC DETECTION(IPAD).............................................................................. - 56 -

9. STRIPPING VOLTAMMETRY..................................................................................................................... - 58 -

9.1 POTENTIOSTATIC STRIPPING.................................................................................................................... - 58 -

9.2 LINEAR STRIPPING VOLTAMMETRY............................................................................................................- 60 -

9.3 STAIRCASE STRIPPING VOLTAMMETRY....................................................................................................... - 62 -

9.4 SQUARE WAVE STRIPPING VOLTAMMETRY..................................................................................................- 63 -

9.5 DIFFERENTIAL PULSE STRIPPING VOLTAMMETRY......................................................................................... - 65 -

9.6 NORMAL PULSE STRIPPING VOLTAMMETRY............................................................................................... - 65 -

9.7 DIFFERENTIAL NORMAL PULSE STRIPPING VOLTAMMETRY............................................................................- 66 -

10. IMPEDANCE(EIS)................................................................................................................................... - 67 -

10.1 EIS VS FREQUENCY(IMP).................................................................................................................... - 68 -

10.2 EIS VS TIME(IMPT)............................................................................................................................- 71 -

10.3 EIS VS POTENTIAL(IMPE).................................................................................................................... - 73 -

11. CHARGING/DISCHARGING.................................................................................................................... - 75 -

11.1 BATTERY CHARGING/DISCHARGING........................................................................................................- 75 -

11.2 GALVANOSTATIC CHARGING/DISCHARGING(GCD).....................................................................................- 76 -

12. BIPOTENTIOSTAT................................................................................................................................... - 77 -

12.1 HYDROGEN DIFFUSION TEST (HDT).......................................................................................................- 77 -

12.2 ROTATING RING-DISK ELECTRODE (RRDE)............................................................................................... - 80 -

13. MISC.TECHNIQUES................................................................................................................................ - 82 -

13.1 ELECTROCHEMICAL NOISE (EN).............................................................................................................- 82 -

13.2 DATA LOGGER.................................................................................................................................... - 83 -

13.3 ELECTROCHEMICAL STRIPPING/DEPOSITION.............................................................................................- 84 -

13.4 BULK ELECTROLYSIS WITH COULOMETRY(BE)...........................................................................................- 86 -

13.5 ELECTROCHEMICAL POTENTIOKINETIC REACTIVATION(EPR)........................................................................ - 87 -

14. GRAPH DISPLAY.....................................................................................................................................- 88 -

14.1 “.COR” DATA GRAPH............................................................................................................................ - 88 -

14.2 “.Z60” DATA...................................................................................................................................... - 91 -

15. TOOLS....................................................................................................................................................- 93 -

15.1 DATA EXPORT.....................................................................................................................................- 93 -

15.2 DATA FITTING..................................................................................................................................... - 93 -

15.3 VOLTAMMETRY ANALYSIS......................................................................................................................- 98 -

15.4 M-S CURVE ANALYSIS........................................................................................................................ - 101 -

15.5 FILTER.............................................................................................................................................- 102 -

15.6 DELETE DATA................................................................................................................................... - 102 -

15.7 EIS ANALYSIS................................................................................................................................... - 103 -

16. WINDOWS...........................................................................................................................................- 109 -

17. HELP.................................................................................................................................................... - 109 -

18. FAQS....................................................................................................................................................- 109 -

18.1 HOW TO INSTALL THE CS STUDIO SOFTWARE?....................................................................................... - 109 -

18.2 WORKSTATION COMMISSIONING.........................................................................................................- 111 -

18.3 HOW TO UNDERSTAND 3-ELECTRODE SYSTEM........................................................................................ - 112 -

18.4 WHAT CAUSE CURRENT OVERLOAD?.....................................................................................................- 112 -

18.5 WHAT CAUSE POTENTIAL OVERLOAD?...................................................................................................- 112 -

18.6 HOW TO CHECK THE RE?................................................................................................................... - 112 -

18.7 HOW TO REDUCE THE NOISE IN ELECTROCHEMICAL EXPERIMENT?..............................................................- 112 -

18.8 TROUBLESHOOTING........................................................................................................................... - 113 -

19. SERVICE & CONTACT US......................................................................................................................- 114 -

20. APPENDIX............................................................................................................................................- 114 -

20.1 COMPARISON: TECHNIQUES FOR EACH MODEL....................................................................................... - 114 -

20.2 ACCESSORIES LIST..............................................................................................................................- 114 -

Manual of CS series Electrochemical Workstation

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Part 1 Introduction of CS series ElectrochemicalWorkstation

CS Potentiostat / Galvanostat (electrochemicalworkstation) contains a fast digital function generator,high-speed data acquisition circuitry, a potentiostatand a galvanostat. With high performance in stabilityand accuracy with advanced hardware andwell-functioned software, it is a comprehensiveresearch platform for corrosion, batteries,electrochemical analysis, sensor, life science andenvironmental chemistry etc.Application

①Electrosynthesis, electrodeposition (electroplating), anodic oxidation, etc.②Electrochemical analysis and sensor;③Battery (Li-ion battery, solar battery, fuel cell, supercapacitor), new materials,

optoelectronic materials;④Corrosion mechanism of metals in water, concrete and soil;⑤Fast evaluation of corrosion inhibitor, water stabilizer, coating and cathodic protection.

Specifications

Support 2-, 3- or 4-electrode system

Potential control range: ±10V

Current control range: ±2A

Potential control accuracy: 0.1%×full range±1mV

Current control accuracy: 0.1%×full range

Potential resolution: 10μV(>100Hz), 3μV (<10Hz)

Current sensitivity: 1pA

Potentiostat rise time: <1μs (<10mA), <10μs(<2A)

Reference electrode input impedance: 1012Ω||20pF

Current range: 2nA~2A, 10 ranges

Compliance voltage: ±21V

Maximum current output: 2.0A

CV and LSV scan rate: 0.001mV~10,000V/s

CA and CC pulse width: 0.0001~65,000s

Current increment during scan: 1mA@1A/ms

Potential increment during scan: 0.076mV@1V/ms

SWV frequency: 0.001~100 kHz

DPV and NPV pulse width: 0.0001~1000s

AD data acquisition: 16bit@1 MHz,20bit@1 kHz


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DAResolution: 16bit, setup time: 1μs

Minimum potential increment in CV: 0.075mV

IMP frequency: 10μHz~1MHz

Low-pass filters: covering 8-decade

Potential and current range: automatic

Communications Interface: isolated Universal Serial Bus (USB 2.0)

Operating System: Windows 2000/XP/ Win7/Win8/Win10

EISSignal generator:

Frequency range: 10μHz~1MHz

Frequency accuracy: 0.005%

AC signal amplitude: 1mV~2500mV

Signal resolution: 0.1 mV RMS

DC Bias: -10~+10V

Output impedance: 50Ω

Waveform: Sine wave, triangular wave and square wave

Wave distortion: <1%

Scan mode: Logarithmic/linear, increase/decrease

Signal analyzer:

Integral time: minimum: 10ms or the longest time of a cycle

Maximum: 106 cycles or 105s

Measurement delay: 0~105s

DC offset:

Potential automatic compensation range: -10V~+10V

Current compensation range: -1A~+1A

Bandwidth: 8-decade frequency range, automatic and manual settingSystem RequirementsOperating System: Windows XP / Vista /7/ 8/10.Communication between PC and instrument: USB2.0.

Dimensions(cm):36 ×30×14; weight: 6.5kg


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Front panel

Front panel of CS Electrochemical Workstation

Electrode cableThe electrode cable is used to connect the testing system to the electrochemical workstation

from the “cell” port:Green lead– connect to the working electrode(WE). This green lead consists of two cables inside:WE and SENS cable. It’s designed like this to mainly avoid potential measuring&control errorresulted from cable voltage drop.Red lead– connect to the counter electrode(CE).Yellow lead– connect to the reference electrode(RE).Black lead– connect to the Faraday cage(if use) or galvanic electrode WE II(if conductingelectrochemical noise test).Indicator lightOv/L – output current is over 120% of the full range when this indicator light is on.Pol – the electrode is on the state of polarization.Pstat- working mode of potentiostatGstat– working mode galvanostat.LPF – light is on when open low pass filter which can reduce the instrument’s bandwidth andenhance the stability.Current range – shows the present current range.ON/OFF – power on and power off.

Rear panel

Rear panel of CS Potentiostat/Galvanostat

AC 220V – the power cable port. (note: we know the power system is 110V in some countriessuch as USA, Canada, we will make the instrument compatible with 110V system accordingly insuch countries.)


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Floating/Earth - switch to “floating”, then the WE lead is completely insulated with the shell ofthe instrument. It’s suitable for electrochemical system where WE is connected to the ground,such as autoclave electrochemical test. Switch to “earth”, then the WE is connect to the shell ofthe instrument(earth), the anti-interference ability will be strong in this case.Interface – to control the external stirrer, span rate of electric machine, or to check the externalsignal frequency as a frequency meter (can connect to EQCM).USB – communication port to connect computer with the instrument.Signal I/O – expansion port for analog input/output. P1 can output analog waveform, such assawtooth wave, sine wave; P2 is the grounding point for all output signals; P3 & P4 is to recordthe external analog signals, such as the temperature, pH sensor etc.

Schematic diagram

Schematic diagram of CS potentiostat

Shipment listFor one set of CS potentiostat/galvanostat, we supply:Instrument host×1

CS Studio software ×1Dummy cell×1Power cable ×1USB cable ×1Electrode cable ×2Manual×1


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Part 2 CS Studio Software1. IntroductionCS Studio software shipped with the CS electrochemical workstation is an easy-to-use, flexible,and versatile electrochemical tool and can be applied in many research fields from corrosion,voltammetry, electroanalysis to battery test, etc. There is no special requirement for computer, amainstream/ common one is OK.

Interface of CS Studio software

1.1 Electrochemical Techniques

Stable polarization: Open Circuit Potential (OCP), Potentiostatic (I-T curve), Galvanostatic,Potentiodynamic (Tafel), Galvanodynamic, Potential Sweep-stepTransient polarization: Multi-Potential Steps, Multi-Current Steps, Potential Stair-Step (VSTEP),Galvanic Stair-Step (ISTEP)Chrono Methods: Chronopotentiometry(CP), Chronoamperometry (CA), Chronocoulometry(CC)Voltammetry: Cyclic Voltammetry (CV), Linear Sweep Voltammetry (LSV), StaircaseVoltammetry (SCV), Differential Pulse Voltammetry (DPV), Normal Pulse Voltammetry (NPV),Square wave voltammetry (SWV), AC voltammetry (ACV), Differential Normal PulseVoltammetry (DNPV), 2nd Harmonic A. C. Voltammetry (SHACV), Fourier Transform ACVoltammetry (FTACV)Stripping Voltammetry: Potentiostatic stripping, Linear stripping, Staircase stripping, Squarewave stripping, Differential Pulse Voltammetry Stripping, Normal Pulse Voltammetry Stripping,Differential Normal Pulse Voltammetry StrippingAmprometric: Differential Pulse Amperometry(DPA), Double Differential Pulse Amperometry(DDPA), Triple Pulse Amperometry (TPA), Integrated Pulse Amperometric Detection (IPAD)Impedance: EIS vs Frequency (IMP), EIS vs Time (IMPT), EIS vs Potential (IMPE)Corrosion testing: Cyclic polarization curve (CPP), Linear polarization curve (LPR),Electrochemical Noise (EN), Zero Resistance Ammeter (ZRA), Electrochemical Potentiokinetic

app:ds:AC

app:ds:voltammetry


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Reactivation(EPR)Battery testing: Battery charge and discharge, Galvanostatic charge and discharge(GCD)Bipotentiostat: Hydrogen diffusion (HDT), Rotating ring-disk Electrode(RRDE)Extensions: Data Logger, Waveform generator, Disc machine control, Bulk electrolysis withCoulometry

CS Studio software is also equipped with powerful corrosion analysis module.It can calculatethe corrosion rate of the material by linear polarization and weak polarization, as well aspolarization resistance (Rp), Tafel slope (ba, bc), and corrosion current density (icorr) through thenon-linear fitting of Tafel plots. In addition, by the built-in electrochemical impedancespectroscopy (EIS)technique, it can measure the double layer capacitance (Cdl) and the solution/concrete resistance(Rs). Moreover,CS Studio software provides as a dual-channel data logger forpH, temperature and some physical quantities records.

1.2 Software Installation

(1) Connect the computer with the workstation by the USB cable. If you use a desktop PC, you’dbetter connect from the rear USB port.(2) Turn “ON”(on the front panel) to start the electrochemical workstation, open the CD or USBflash disk to find the driver and installation applications.Click the “USB Drives”(shown below),then click CP210xVCPInstaller_x64.exe(64 bit OS) or CP210xVCPInstaller_x86.exe(32 bit OS)based on your operation system.


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(3). After finishing the driver installing, in the device manager → Ports (COM & LPT), therewill be “CP210x USB to UART Bridge (COMX)”, X=1~6, as shown below, the X is 3.

(4) Double-click the “Corrtest Install”, and then the testing and analyzing software “CS Studio5.***” to install the software step by step following the instructions.


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(5)The software will be installed in the specified directory, and create a shortcut icon on thedesktop, as shown below:

2. MenuThere are key shortcuts for experiment techniques, such as “F2” for “Open Circuit Potential”,

F4 for technique of “Potentiodynamic”.There is a toolbar under the main menu, and it can achieve the same function as the main

menu, and there will be a text message tip when you put the mouse on.the “Experiments” will appear when you right-click the mouse on anywhere of the window.

You can choose one technique to perform. Of course you can clicking main menu of“Experiments” and then click one technique..

The button will be activated when a test is running. You can click it to stop the test. Thisbutton will gray out when you finish a test.

2.1 File

2.1.1 Open FileOpen a “.cor” data file. You can view data and do analysis. .

2.1.2 New Project

Build a new project window. The original project window will not be closed or replaced.2.1.3 Open Project

Open a project file.You can view the file and do data analysis.2.1.4 Save Project

Save the project window file in project file format.2.1.5 Save Project As

Save data file or project file as a new project file.2.1.6 Close Project

Close an open project window. If no file is open, this menu is disabled.2.1.7 Page Setup

Set the format for printing output .2.1.8 Print

Output the graph of the open file to the printer.2.1.9 Exit

Exit the CS Studio software. When a test is being performed, there will be a prompt.

2.2 Setup


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2.2.1 Connection

This menu is to set the connection way of the instrument.

2.2.2 Timing MeasurementYou can do unattended experiments by timing measurement mode.It achieves the unattended automatic measurement at a fixed interval that you set after the

specified time. This mode facilitates the work of tracking the characteristics of a testing systemas a function of time.

Start button is not activated until you enter a valid file name. All testing data files will be savedin the same directory that you specified.File Name --For long-term timing measurement, the subsequent data files (abc_1.cor, abc_2.cor,abc_3.cor ...) will be automatically saved.In the dialog box, you can specify the time when the measurement is started, the interval of

measurements, and the total times of measurements.The current cycle is the number of measurements that have been conducted.When you select an experiment for timing measurement, the parameters setting will be the

same as last time when this experiment is performed. You can modify them and then they will be


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written in the software for timing measurement use.For polarization experiments(eg.potentiodynamic, cyclic voltammetry, electrochemical

impedance...), the instrument will automatically leave polarization state after each measurementis finished and the cell stays open circuit until the next measurement.When the total times of measurement is reached, timing measurement window will

automatically exit.

2.2.3 Combination TestCombination test is helpful for the user to self-define the experiments. The user can

conduct different experiments by adding them from the experiment drop-down box. For eachexperiment, the parameter setting and number of cycles can be set as you want. After theexperiments and instruction are all set, click “Start”, the instrument will run all theexperiments one by one and save data automatically.

Plan- it shows the combination test plan which is performing at present. Rename is used tomodify the plan’s name, Add is to add a new plan of combination test.The Delete is to get rid ofthe combination test plan that you don’t need.The added experiments for combination test is shown here. You can click to change the

experiments order.

2.2.4 ExtendWhen CS electrochemical workstation is working alone, you don’t need to use the function

of “Extend”, just check “none”. When the normal CS electrochemical workstation CS350 isconnected to CS1005 (current amplifier) or CS1120 (power amplifier), please check respectively.


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2.2.5 Reset WorkstationClick “Yes” to restore the factory default settings.

3. Experiment Setting3.1 Pstat/Gstat(ECS)Setting

Open a technique, and you can do the instrument setting by clicking .


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Potential RangePotential range can be ±2.5V, ±5V, or ±10V. The default range is ±2.5V. The narrower the rangeis, the higher the input signal gain. Normally when the potential signal input is in the range of±2.5V, “±2.5V” range is OK. But if the potential of the tested system is over ±2.5V, you mustchoose the range to be ±5V, or ±10V.Current RangeYou can choose either “Manual” or “Auto”. If check Manual, the drop-down box is activated,and you can choose a suitable current range. If the current in the experiment is over 120% of theset range, then the software will automatically cut off the polarization of the potentiostat. “Auto”allows the instrument to select the suitable current range according to the polarization current.“Min Range” - you can set a limitation for minimum current range to avoid possible extra noisein some high-resistance systems in case the current range is too small.“Only Inc” means the current range will be switched only from lower range to higher range, justin this direction. This is particularly useful for CV technique.In the moment of current range switching, noise may be inevitable. Therefore, it is

recommended to choose a fixed current range in fast measurements or when the data acquisitionfrequency is high.OCPCheckIf you check the radio button “Use”, the software will judge whether the open circuit potential isin the range that you set. If yes, the experiment will conduct automatically if you have set thedata file save path.Quiet TimeEnter a number or drag the slider, you can specify the duration of delay for scan. The

maximum delay time is 1000s. Setting the quiet time can make the measuring current stable,especially when polarization doesn’t start from OCP. As you know, transient polarization maycause a large current, and the value will decrease as time goes by. Therefore, there should be aquiet time before formally recording data.

Before this window appear, the potentiostat is already in the state of polarization, but doesn’tstart scan. If you think the polarization current is already stable, then you can click Run anytimeto start testing. You can click cancel to quit the experiment.When the countdown is completed, the scan will start automatically.If you set “Auto” change current range, during this process, CS studio software will auto

choose the suitable range according to the actual current. If the current range is set to be“manual”, once the current is overloaded, the software will give you a prompt to change a largercurrent range. If you choose “No”, then the software will control the instrument to change frompolarization state to natural state.


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IR CompensationIn high-resistance system, the solution resistance(Rs) is large between the working electrode

and the tip of Luggin capillary where the reference electrode is put, especially for concrete orcoated samples, so it must be compensated. Rs measurement can be done with method ofPotential Stair-Step (VSTEP). Enter the Rs value in the feedback for IR compensation in thesubsequent measurements.Ground modeThere are two modes for the working electrode: virtual and real. The “virtual” mode is suitable

for most stable test systems. As for electrochemical noise or galvanic corrosion measurement,you must choose “virtual” mode. Real mode is suitable for a system where the working electrodeis connected to earth, such as the rebar in the concrete. For EIS test, you should choose realmode to increase the high-frequency response characteristic.PolarityWhen choose the normal “O2+”, a more positive potential will produce a bigger oxidation force,

meanwhile the generated current is positive. In a typical water environment(pH=0), when thepotential is +1.23V(vs NHE), the oxygen will precipitate on the surface of the working electrode.If choosing the reverse “O2-”, a more negative potential will produce a bigger oxidation force, theoxidation current value is negative. At this time, in a typical water environment (pH=0), whenthe potential is - 1.23V(vs NHE), oxygen will be precipitated on the surface of the WE.Low Pass FilterThe frequency response bandwidth of the power amplifier in the potentiostat can be change

by this setting. The higher the capacitance you choose is, the narrower the bandwidth of thepotentiostat is.If all the filters are closed, then the power amplifier has the best frequency response

characteristics. But for some high-resistance systems, oscillation may appear. If you use thevirtual mode and choose a low capacitance, it is very likely for the instrument to occuroscillation even positive feedback. You should decrease the bandwidth of the amplifier, i.e.,increase the capacitance in the low pass filter.When increasing the capacitance, the response frequency bandwidth will decrease, which

equals to low-pass filtering the signals. Normally, for slow scan experiment, you can choose10nF~100nF; for fast scan or transient measurements, you can choose 100pF~10nF; For EISmeasurements, you may need to choose 100pF~10nF(virtual) or 0~1nF(real).Data smoothWhen choosing data smooth, the software will do real-time filtering of the data and

automatically get rid of the burrs on the curves. Please note that when you do transientmeasurements, you don’t need to use it because it can bring slight distortion for data.Notch filterIf you check the notch filter and choose the frequency, the interference can be restrained when

the experiment is being conducted.3.2 Cell Setting

You can enter related information of one or more working electrode(s) and electrolytic cell(s),eg. surface area, material, and temperature... These parameters will not affect the original data,they are just saved in each data file for info. Meanwhile, these parameters are needed forcorrosion rate calculation.


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Electrode parametersElectrode Area: the exposed area of the working electrode in the solution. It is the effectiveworking area. Unit is cm2.Density: the density of the material of the working electrode. Unit is g/cm3.Chemical Equiv = the molar mass/number of electrons transferred in a reaction. Take the reactionFe→ Fe2+ for example, the molar mass of pure Fe is 55.84g, and the number of transferredelectrons is 2, so the equivalent weight is 55.84g/2=27.92g.Cell parametersReference electrode: in the drop box you can choose SCE, Ag/AgCl, Hg/HgO, Hg/HgSO4,Cu/CuSO4... You can also choose “Custom” if your RE is not in the list, then you should specifythe value of “V vs. NHE (normal hydrogen electrode) ”.V vs NHE: it is the relative potential of the selected reference electrode vs. NHE.Temperature: it is the temperature for the electrochemical reaction at present.Stern- Geary Coef.: in the range of 20~28mV.Active channelFor single-channel CS potentiostat, there is only 1 channel. For multi-channel potentiostat,

you can set the cell information independently.


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4. Stable Polarization4.1 Open Circuit Potential

Experiments→Stable Polarization→Open Circuit PotentialThis experiment aims at monitoring the open circuit potential (or free corrosion potential,

i.e., the potential difference between WE and RE without any applied electric field) as a functionof time. The experiment can be performed for a fixed duration or until a particular potential isreached.

Before test, the OK button is invalid. Only when you enter a file name can this button beactivated. All the data will be saved in this file.

OCP (V) will display the current open circuit potential of the cell (update every second).4.1.1 File Name

The user should enter a file name to save data before starting the test. At the first time, whenYou input a name and click OK, you will see the default data storage path on the top of thetesting window. Or you can click the Browse, and choose the storage path as you want. This isparticularly useful if you forget the file names that you already use. Once you choose the path, itwill be the default storage path of the following data files unless you click “Browse” and chooseanother path again.

CS Studio will automatically append the suffix “.cor” to a file name. So if you input “tutor1”,the name of the data file will be shown as “tutor1.cor”.

The info in the Comments box will be saved in the data file. You can input info. such asthe medium, the solution content, etc. Other info. such as the time when you perform the test,and all the related measurement parameters will be automatically saved in the data file. You don’tneed to enter such information into comments.4.1.2 Experiment

The Total Time decides the total duration of the experiment OCP. Unit is second, minute orhour.


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4.1.3 Data AcquisitionChoose either “Interval” or “Frequency”.Interval determines the time between each sampled data point. Frequency(Hz) specifies the

data points sampled per second(acquisition rate). Please note that the interval cannot be set lowerthan 0.001s, i.e., the points/second cannot be higher than 1000. Otherwise the software willautomatically set the frequency to be 1kHz (the maximum value allowed).4.1.4 Experiment Termination

If the Use is checked, the experiment will be automatically terminated once the open circuitpotential goes above the high value (2V in the above dialog box for instance) or below the lowvalue (-2V) .4.1.5 Axis Type

You should set the Axis type for display of each dynamic graph. For OCP, the axis type is“E-Time”.4.1.6 Pstat/Gstat(ECS)

See 3.1Pstat/Gstat(ECS) Setting4.1.7 Cell Setup

See Cell Setting 3.2.Click OK to exit the parameter setting dialog box, and enter the “wait…” interface before

testing. Meanwhile, CS Studio will save all the parameters that you set and remain the same thenext time when you run this experiment.

Click “Cancel” also to exit the dialog box, not conducting the experiment. All the setparameters will be lost.

Click Help to access to the on-line help information on the setup of this experiment.4.2 Potentiostatic

Experiments→Stable Polarization→PotentiostaticIn this experiment, the potentiostat applies a constant polarization potential on the working

electrode and monitor the polarization current as a function of time. The polarizationduration(Total Time) can be set by the user, or you can also let the experiment be automaticallyterminated when the polarization current or quantity of electric charge reaches to a certainvalue(change from the polarization state to OCP state).


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OCP (V) will display the current open circuit potential of the cell (update every second).

4.2.1 File NameSee 4.1.1 File Name.

4.2.2 Experiment ParametersApplied Potential is the potential applied on the measured system. It can be potential “vs.

OCP” or “vs. RE”.For CS series potentiostat, choosing potential “vs. OCP”, then input of a positive value

means anodic polarization, negative value means cathodic polarization. Then the actual potentialapplied on the WE is the algebraic sum of the input value and the current open circuit potential.For example, enter “0.2”, then the actual potential of the working electrode (vs. RE) is“0.2V+OCP”. If selecting “vs. RE”, then the polarization potential of the working electrode (vs.RE) is just 0.2V.

The Total Time determines the total time of potentiostatic polarization. Unit is Second,minute or hour.4.2.3 Experiment Termination

If the Use I box is checked, the experiment of potentiostatic will be automatically terminatedonce the polarization current goes above the high value(anodic current, 250mA in above dialogbox for instance) or below the low value (cathodic current, -250mA in above dialog box forinstance) .

If Use Q is checked, the experiment of potentiostatic will be automatically terminated oncethe total integral quantity of electric charge (coulombs) goes over maximum value(positivecharge) or below minimum value(negative charge).

If the Disable is checked, the above two experiment termination prerequisites are ineffective.The experiment will not be terminated until the total time is reached.


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4.2.4 Data AcquisitionSee 4.1.3 Data Acquisition.

4.2.5 Axis TypeWhen the experiment is performed, the data will be displayed as specified by the Axis Type.

CorrView can be later used to display the data in other formats. For the experiment ofPotentiostatic, the axis type is “I-Time”.4.2.6 Pstat/Gstat(ECS)

See 3.1 Pstat/Gstat(ECS) Setting4.2.7 Cell Setting

See Cell Setting 3.2.4.3 Galvanostatic

Experiments→Stable Polarization→GalvanostaticIn this experiment, the instrument applies a constant polarization current on the working

electrode and monitor the polarization potential as a function of time. The polarization duration(Total Time) can be set by the user, or you can also let the experiment be automaticallyterminated when the polarization potential or quantity of electric charge reaches to a certainvalue.


See 4.1.1 File Name.4.3.2 Experiment

Applied Current is the current applied on the measured system. Positive value meansanodic polarization; negative value means cathodic polarization. This is the total current applied,not the current density. Units of A, mA, A are available.


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The Total Time determines the duration of the galvanostatic polarization process.4.3.3 Experiment Termination

If the Use E box is checked, the experiment of galvanostatic will be automaticallyterminated once the polarization potential goes above the high value(2V in above dialog box forinstance) or below the low value (-2V in above dialog box for instance) .

If Use Q is checked, the experiment of galvanostatic will be automatically terminated oncethe total integral quantity of electric charge (coulombs) goes over maximum value or belowminimum value.

If the Disable is checked, the above two experiment termination prerequisites are ineffective.The experiment will not be terminated until the total time is reached.4.3.4 Data Acquisition

If Frequency(Hz) is chosen, the acquisition rate in points/second is specified.4.3.5 Axis Type

When the experiment is performed, the data will be displayed as specified by the Axis Type.CorrView can be later used to display the data in other formats. For the experiment ofGalvanostatic, the axis type is “E-Time”.4.3.6 Pstat/Gstat(ECS)


See Cell Setting 3.2.4.4 Potentiodynamic

Experiments→Stable Polarization→PotentiodynamicFor technique of potentiodynamic, there are up to four individual polarization potential set

points. The scan starts from the “initial E” and goes through “vertex E #1”, “vertex E #2”, andfinally reaches “final E”. The “vertex E #1” and “vertex E #2” can be both chosen, partly chosenor neither chosen by the Use box. The scan can be stopped or reversed when current reaches to acertain value. The logarithm of current is recorded as a function of potential.


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See 4.1.1 File Name.4.4.2 Experiment Parameters

If you check neither vertex E#1 nor vertex E#2, then the potential is scanned directly fromInitial E towards Final E. For example, if you enter “-0.1” (vs. OCP) in the initial E, and “0.1”(vs. OCP) in the final E box, then the potential is actually scanned from cathodic polarization100mV to anodic polarization 100mV. Of course when the polarization current density hasalready entered the range to terminate the experiment before the potential reaches 10mV, the scanwill stop, and cut off the polarization state of the potentiostat. If potential is “vs. OCP”, thennegative value means cathodic polarization, and positive value means anodic polarization.

Scan Rate: It can only be a positive value. Scan direction is determined by the sign of theapplied potential. Scan time =scan amplitude/scan rate. Total measuring time=∑(|amplitude ofpolarization potential of each segment|/scan rate)

Experiment TerminationIf check “Stop scan”, when final potential is reached or the polarization current density is

higher than the maximum value (e.g.2mA/cm2) or lower than the minimum set value(e.g.-2mA/cm2), the experiment will be stopped automatically.

If check the “Reverse scan”, when polarization current reached the range that you set, thescan direction will be reversed, from current potential to initial potential. If the current density islower than the minimum value you set during cathodic retrace scan, the scan will beautomatically stopped.

If neither is checked, the experiment will be conducted according to the potential settings.Normally, to protect the working electrode from excessively high current, you can choose Stopscan and set a maximum anodic current.4.4.3 Data Acquisition

If Frequency(Hz) is chosen, the acquisition rate in Points/Second is specified.


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4.4.4 Axis TypeIn the experiment of potentiodynamic, you can choose “E vs. Logi”.

4.4.5 Pstat/Gstat(ECS)See 3.1 Pstat/Gstat(ECS) Setting

4.4.6 Cell SettingSee Cell Setting 3.2.

4.4.7 Passivation curveIn potentiodynamic test, sometimes we need to measure passivation curves of some metals

such as chromium, nickel, cobalt and their alloys in certain medium. It will produce a layer ofpassivation film on the surface of these metals when their potential is relatively positive. At thismoment, they are similar to noble metals in behavior, with slight passivation current flowing. Inorder to evaluate their anti-corrosion performance, it is necessary to obtain the cracking potentialand protection potential. Therefore, the passivation curve is graphed.

Typical passivation curve

When the polarization potential is scanned towards positive to a certain value, thepassivation film will be cracked, then the polarization current will increase rapidly, thispolarization potential is called cracking potential φb. When the current exceeds a certain value(eg. 100A/cm2), the potential will immediately be scanned towards negative, there will be ahysteresis loop on the polarization curve. The intersection of the positive curve and the flybackcurve is considered to be the protection potential of the metal in this medium φp.

4.5 Galvanodynamic

Experiments→Stable Polarization→GalvanodynamicFor technique of galvanodynamic, there are up to four individual polarization current set

points. The scan starts from the “initial current” and goes through “vertex i #1”, “vertex i #2”,and finally reaches “final i”. The “vertex i #1” and “vertex i #2” can be both chosen, partlychosen or neither chosen by the Use box. The scan can be stopped or reversed when potentialreaches a certain value.


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OCP will display the current open circuit potential of the cell (update every second).4.5.1 File Name


If you check neither vertex i#1 nor vertex i#2, then the current is scanned directly fromInitial i towards Final i. For example, if you enter “-100” (unit:μA) in the initial i, and “100” inthe final i box, then the current is actually scanned from cathodic polarization 0.1mA to anodicpolarization 0.1mA. Of course when the polarization potential has already entered the range toterminate the experiment before current reaches 0.1mA, the scan will stop, and cut off thepolarization state of the potentiostat.

Negative value means cathodic polarization, and positive value means anodic polarization.Scan Rate: It can only be a positive value. Scan direction is determined by the sign of the

applied current.4.5.3 Experiment Termination

If check the “Stop scan”, when the final current is reached or the polarization potential meetsthe condition to terminate the experiment, the scan will be automatically stopped.

If check the “Reverse scan”, when polarization potential reaches the range that you set, thescan direction will be reversed, from current current to initial current, and when the polarizationpotential is lower than the minimum value you set, the scan will stop. .

If neither is checked, the experiment will be conducted according to the current settings.

4.5.4 Data AcquisitionIf Frequency(Hz) is chosen, the acquisition rate in Points/Second is specified.


CorrView can be later used to display the data in other formats.


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4.6 Potential Sweep-step

Experiments→Stable Polarization→Potential Sweep-step

In the Potential Sweep-step, the instrument alternates between six potential sweeps and sixpotential steps, somewhat like an arbitrary waveform generator. The following diagram showsthe potential waveform applied as a function of time. One can skip any segment by settingparameters sufficiently small, allowing enhanced flexibility for waveform control. Current isrecorded as a function of time; for sweep segments, it can also be presented as a function ofpotential.


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Parameter setting dialog box

Segment Parameters Range Remarks

1, 3, 5, 7, 9, 11 Init E /V -10~+10 Initial potential in sweep segment

Final E /V -10~+10 Final potential in sweep segment

Scan rate /V·s-1 1E-6~50 Potential scan rate in sweepsegment

2, 4, 6, 8, 10,12 Step potential /V -10~+10 potential value in step segment

Step time /s 0~10000 duration of step segment

1~12 Step potential/V vs. RE or vs.OCP

choose the potential output mode



CorrView can be later used to display the data in other formats.4.6.3 Pstat/Gstat(ECS)

See 3.1 Pstat/Gstat(ECS) Setting.


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5. Transient Polarization5.1 Multi-Potential Steps

Experiments→Transient Polarization→Multi-potential StepsIn the Multi-potential Steps technique, up to twelve potential steps can be applied and cycled.

Current is recorded as a function of time.

OCP will display the current open circuit potential of the cell (update every second). If theinstrument is turned off, this value will display “Not Available”.5.1.1 File Name

See 4.1.1 File Name.


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5.1.2 Experiment ParametersThe steps start from the Initial E, then to Step 1E, Step 2E, Step 3E,…towards Final E. If the

time of a step is “0” or the box before it is unchecked, this segment will be skipped.Potential can be specified as “vs. OCP” or “vs. RE”.Cycles specifies how many times the potential is stepped between Initial E and Final E.Time determines the duration of the step potential being held.

5.1.3 Data AcquisitionIf Frequency(Hz) is chosen, the acquisition rate in points/second is specified.

5.1.4 Axis TypeAxis Type is I vs. time for multi-potential steps.



5.2 Multi-Current Steps

Experiments→Transient Polarization→Multi-Current StepsIn the Multi-Current Steps technique, up to twelve current steps can be applied and cycled.

Potential is recorded as a function of time.

OCP will display the current open circuit potential of the cell (update every second). If theinstrument is turned off, this value will be“Not Available”.5.2.1 File Name

See 4.1.1 File Name.5.2.2 Multi-Current Steps Parameters

The steps start from the Initial i, then to Step 1i, Step 2i, Step 3i,…towards Final i. If thetime of a step is “0” or the box before it is not checked, this segment will be skipped.

Cycles specifies how many times the current is stepped between Initial i and Final i.


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Time determines the duration of the step current being held.5.2.3 Data Acquisition

If Frequency(Hz) is chosen, the acquisition rate is set as Points/Second.5.2.4 Axis Type

Axis type for multi-current steps is E vs time.5.2.5 Pstat/Gstat(ECS)


See Cell Setting 3.2.5.3 Potential Stair-Step (VSTEP)

Experiments→Transient Polarization→Potential Stair-StepPotential Stair-Step can be used to measure the solution resistance Rs and polarization

resistance Rp, it can also be applied to calculate the double-layer capacitance Cdl .There are up to 3 individual potential setpoints for potential Stair-step. If the Use box is

checked, the mode of the stair step is Initial E→Step1 E→Step2 E to finish two segments of stairstep measurement.

OCP will display the current open circuit potential of the cell (update every second). If theinstrument is turned off, this value will be “Not Available”.5.3.1 File Name


The steps start from Initial E, to Step E1, and then to Step E2. If “Use” box is unchecked, thesegment of the Step E2 will be skipped.

Time determines the holding time of a step potential.


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5.3.3 Data AcquisitionIf Frequency(Hz) is chosen, the acquisition rate in Points/Second is specified. Because the

step process is fast, the data acquisition rate is also fast, 1~3KHz is recommended.5.3.4 Axis Type

Axis Type is I vs. time.5.3.5 Pstat/Gstat(ECS)

In step test, because the measuring time is very short, the current range should only bechosen manually in advance, not determined by the software automatically.5.3.6 Cell Setting

See Cell Setting 3.2.5.4 Galvanic Stair-Step(ISTEP)

Experiments→Transient Polarization→Galvanic Stair-StepThere are up to 3 individual current setpoints for galvanic Stair-step. If the Use box is

checked, the mode of the stair step is Initial current→Step1 E→Step2 E to finish two segments ofstair step measurement.

OCP will display the current open circuit potential of the cell (update every second). If theinstrument is turned off, this value will be “Not Available”.5.4.1 File Name

See 4.1.1 File Name.5.4.2 Scan Parameters

The steps starts from the Initial Current, to Step i#1, and then to Step i#2. If the Use is notchecked, the segment of the Step i #2 will be skipped.

The Time determines how long the current will be held at each step.5.4.3 Data Acquisition

If Frequency(Hz) is chosen, the acquisition rate in Points/Second is specified.Owing to the


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fast process of step, the data acquisition rate is fast too. The frequency is normally set between1~3KHz.5.4.4 Axis Type

When the experiment is performed, the data will be displayed as specified by the Axis Type.CorrView can be later used to display the data in other formats.5.4.5 Pstat/Gstat(ECS)

See 3.1 Pstat/Gstat(ECS) Setting.5.4.6 Cell Setting

See Cell Setting 3.2.6. Chrono Techniques6.1 Chronopotentiometry

Experiments→Chrono Techniques→ChronopotentiometryIn Chronopotentiometry (CP), two current levels can be specified to pass through the

working electrode, with the switching between the two dictated by time or potential. Potential isrecorded as a function of time.



Cathodic/anodic current is applied on the working electrode during the test. You can choosethe unit of the current.

Cathodic/anodic time is the duration of the applied cathodic/anodic current. Second, minute


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and hour can be selected.CS Studio can achieve cathodic-anodic reverse by setting the high E and low E.Number of Segments specifies how many times the current is cycled between cathodic and

anodic current. When the number of current polarity switches (segments) is reached, theexperiment stops.

Parameters Range Description

Cathodic current -2A~+2A The cathodic current applied on the working electrode

Anodic current -2A~+2A The anodic current applied on the working electrode

Cathodic time >0 Duration of cathodic current

Anodic time >0 Duration of anodic current

Initial polarity Anode/cathode The polarity at the beginning of the experiment

Number of segment >0 The number of applied cathodic and anodic current

High E (V) -10~+10 The current will be reversed when reach the specified value

Low E (V) -10~+10 The current will be reversed when reach the specified value

6.1.3 Current Switching PolarityThis setting can be used to reverse the anodic polarization and cathodic polarization process.

For example,as shown in above picture of the parameter setting window, if the potential reaches1V in less than 10s, then the reverse is triggered, proceeding the cathodic polarization. If thepotential reaches -1V in less than 10s, anodic polarization is triggered.

The current switching polarity can be checked when either the specified potential or thespecified time has been reached. If the limiting potential is reached, the current polarity will stillbe reversed in order to protect the electrode.6.1.4 Data Acquisition

If Frequency(Hz) is chosen, the acquisition rate in Points/Second is specified.6.1.5 Axis Type



See Cell Setting 3.2.6.2 Chronoamperometry

Experiments→Chrono Techniques→Chronoamperometry

Chronoamperometry method is a function of measuring the current response as a function oftime after applying a single or dual potential step on the working electrode. Electrodes of fixedarea are often used in this method. It is suitable for studying the electrode process of couplingchemical reaction, especially the reaction mechanism of organic electrochemistry.

In Chronoamperometry (CA), the potential is stepped from Init. E to either High E or Low Edepending on the Init. P/N and may then be stepped back.A fast-rising potential pulse is enforced on the working-sense electrode of an electrochemical


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cell; the current flowing through this electrode is measured as a function of time. Technique isalso referred to as CA.For a Two-Step Chronoamperometry experiment, either insert two CA actions into the samesequence (each set at the desired Potential step and with the cell remaining ON at the end of thefirst step) or preferably, run a two-step Fast Potential Pulse action if that is available.


See 4.1.1 File Name.6.2.2 Scan ParametersThe experiment starts at the Initial Potential, sweeps to High E, and then to Low E. A potential

can be specified in several ways. If ‘vs.OCP’ is chosen, the specified potential is added to theopen circuit potential of the cell. “vs.RE” is used to select an exact potential to be applied.Pulse Width specifies how long the potential is sustaining.Number of Steps specifies how many potential cycles are formed between High E and Low E.


Initial E (V) -10~+10 Initial potential

High E (V) -10~+10 Upper limit of potential step applied on the WE

Low E (V) -10~+10 Lower limit of potential step applied on the WE

Pulse width (S) >0 Duration of the applied potential pulse

Number of steps >0 Number of cycles



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See Cell Setting 3.2.6.3 Chronocoulometry

Experiments→Chrono Techniques→ChronocoulometryChronocoulometry is a method to measure the quantity of electric charge as a function of

time after a potential step is applied on the working electrode. This method can study electrodeprocess in all kinds of coupling reactions. It can also study the electroactive adsorption.

A fast-rising potential pulse is applied on the working-sense electrode of an electrochemicalcell.The current flowing through this electrode is measured and integrated, reporting coulombs asa function of time. Technique is also referred to as CC.

For bulk electrolysis measurements, a Pre-electrolysis parameter is provided to electrolyzeand subtract out solvent background currents, with the sample of interest added after thePre-elect (s) stage to measure the total charge associated with the sample, minus the backgroundcurrent contributions.


See 4.1.1 File Name.


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6.3.2 Scan Parameters


Initial E (V) -10~+10 The potential applied on the working electrode

Final E (V) -10~+10 The potential applied on the working electrode

Pulse width(s) 0.001~10 Duration of the applied potential pulse

Number of steps 0~ 1000 Number of cycleThe potential may be swept between up to 2 separate setpoints in this experiment. The

experiment starts at the Initial Potential, and then to the Final Potential. A potential can bespecified in several ways. If “vs. OCP” is chosen, the specified potential is added to the opencircuit potential of the cell. “vs.RE” is used to select an exact potential to be applied.

Pulse Width specifies how long the potential is sustaining.Number of Steps specifies how many times the potential is cycled between Initial Potential

and Final Potential.6.3.3 Data Acquisition




See Cell Setting 3.2.7. Voltammetry7.1 Cyclic Voltammetry

Experiments→Voltammetry→Cyclic VoltammetryCyclic Voltammetry is a technique used for the theoretical study of redox couples. Cyclic

Voltammetry is a special LSV that performs a triangular-shaped scanning at the workingelectrode. In this way, a redox couple in solution is exposed to an oxidation and afterwards to areduction.

The plot of a cyclic voltammetry consists on a closed curve: reversible redox couples showboth cathodic and anodic peak, while irreversible redox systems show only one peak.

The following formulas can be useful to establish the standard potential of a reversible redoxcouple and figure out the number of electrons involved in the discharge process:

1/228.25

paE En

Where Epa = anodic peak potential

nEE pc

25.282/1

Epc= cathodic peak potential.

nEEE PCpap

5.56


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A two-stage voltage ramp is programmed from an initial potential to a vertex potential, andthen from the first vertex potential to the second one at a defined scan rate. The scan can berepeated for many times (cycles) between the two vertex potentials. To keep the step size on an“analog-like” level, the maximum scan rate should be 10,000V/s. To control the number ofpoints acquired, the data acquisition should be separated from any particular points, and spreadout over the entire scan range to a maximum of 1000 points per cycle.

Parameters setting dialog boxThis experiment applies a potential sweep between up to 4 separate potential setpoints. If

2 setpoints are used, multiple cycles will be performed.OCP will display the current open circuit potential of the cell (update every second). If the

instrument is turned off, this value will display “Not Available”.7.1.1 File Name



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Initial E(V) -10~+10 Start E of potential scan

Step 1E(V) -10~+10 Start E of the potential scan or the first vertexfrom initial E.

Step 2 E(V) -10~+10 the second vertex of potential scan

Scan rate(mV/s) 10-5~10000 The scan rate of the potential

Cycles 1~10000 The times of the cycle

Interval (mV) > 0.01 Potential difference between two sampling points

Frequency (Hz) 0.01~1000 Sampling as per frequencyThe potential may be swept between up to 4 separate setpoints in this experiment. The

experiment starts at the Initial Potential, sweeps to High E, to Low E, and then to the FinalPotential. Click on the “Use” boxes to turn on or turn off the Initial and Final setpoints. If theInitial or Final setpoint is unchecked, this segment of the sweep will be skipped. For example, ifonly the Initial is checked, the sweep Initial→High E→Low E will be performed. If neither theInitial nor Final is checked, High E→Low E will be performed.

A potential can be specified in several ways. If “vs. OCP” is chosen, the specified potentialis added to the open circuit potential of the cell. For example, “0.1V vs. OCP” means applying apotential of 0.1 Volts above the measured open circuit potential. “vs.RE” is used to select anexact potential to be applied.

The Scan Rate selects how fast the potential is scanned between one potential and another.No. of Cycles specifies how many times potentials are cycled between High E and Low E.


7.1.4 Axis Type:When the experiment is performed, the data will be displayed as specified by the Axis Type.




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7.2 Linear Sweep Voltammetry

Experiments→Voltammetry→Linear Sweep VoltammetryA single voltage ramp programs from an initial potential to a final potential that progresses

at a defined scan rate. To keep the step size on an “analog-like” level, the maximum scan rateshould be 1000V/s. To control the number of points acquired, the data acquisition should beseparated from any particular point, and spread out over the entire scan range to a maximum of1000 points per scan.

OCP will display the current open circuit potential of the cell (update every second). If theinstrument is turned off, this value will be “Not Available”.


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7.2.2 Scan ParametersUp to 2 separate potentials can be applied during the experiment. The experiment starts at

the Initial Potential, and then to the Final Potential.The potential can be specified in several ways. If “vs. OCP” is chosen, the specified

potential is added to the open circuit potential of the cell. For example 0.1 V vs Open Circuitmeans applying a potential of 0.1 Volts above the measured open circuit potential. “vs. RE” isused to select an exact potential to be applied.

The Scan Rate determines how fast the potential is scanned between one potential andanother.7.2.3 Data Acquisition




See Cell Setting 3.2.7.3 Staircase Voltammetry

Experiments→Voltammetry→Staircase VoltammetryIn Staircase Voltammetry (SCV), the potential is incremented from Initial E toward Final E,

and it may be scanned back. Current is sampled after every potential increment and recorded as afunction of potential.


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Init E and Final E should be at least 0.01 V apart. ‘vs. Reference’ is used to select an exactpotential.

Inc.E is the increment potential of each pulse; it can be chosen from 0.001V to 0.05V.Step Period can be chosen from 0.01s to 50s.No. of Cycles specifies how many times potential are cycled between Initial E and Final E.





See Cell Setting 3.2.7.4 Square Wave Voltammetry

Experiments→Voltammetry→Square Wave VoltammetryThe potentiostat applies a series of forward and reverse pulses (both equal in duration, and

defined as a frequency) superimposed on a linear staircase scan. The resulting currents can be


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subtracted from one another to plot the current difference, which is helpful for improving thesensitivity of analytical measurements. Technique is also referred to as SWV.

Parameters setting dialog box


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SWV curve in K3Fe(CN)6 systemOCP will display the current open circuit potential of the cell (update every second). If the

instrument is turned off, this value will be “Not Available”.7.4.1 File Name


In Square Wave Voltammetry (SWV), the base potential is incremented from Init E towardsFinal E. A square wave potential is superimposed onto the base potential, which increments aftereach cycle of the square wave. Current is sampled at the end of the forward and reverse steps andrecorded as a function of the base potential. During the experiment, only the difference betweenthe two current samples is displayed.

Init E and Final E should be at least 0.01V apart. “vs.RE” is used to select an exactpotential to be applied.

Inc.E is the increment potential of each pulse; it can be chosen from 0.001V to 0.05V.Amplitude can be chosen from 0.001V to 0.5V.Frequency can be chosen from 1Hz to 100,000Hz.





See Cell Setting 3.2.7.5 Differential Pulse Voltammetry

Experiments→Voltammetry→Differential Pulse VoltammetryDifferential pulse voltammetry is a method to measure the electrode potential as a function

of time after applying a fixed-amplitude potential pulse on the linearly increased scanningpotential. The current is sampled before and after the potential pulse. The difference of the twocurrents is recorded in the form of the potential function.


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Before and after each pulse, the current was measured twice, and the difference between thetwo currents was recorded. The difference vs. potential is plotted to obtain a differential pulsevoltammetry curve. The peak current and peak potential are two important parameters.

For the reversible system, the curve is symmetric, and the peak current and the measuredsubstance concentration is proportional. When the amplitude of the applied pulse is small, therelation can be expressed by the following equation:

CtDEA

RTFnIP

m

4

22

Where, E is the amplitude, A is the area of the electrode, tm is the time between applyingpulse and sampling current. D is the diffusion coefficient of the measured material. From theequation, we can see that the peak current is related to the amplitude of the potential pulse. Butif the amplitude is too large, it will influence the resolution. Generally speaking, it is better toset amplitude to be 25~50mV, scan rate to be 5mV/s.

Because this method can effectively get rid of the effect of the background current, thesensitivity can be enhanced dramatically. The minimum measured concentration can be10-8mol/L

DPV is very useful for analytical determination (for example, metal ion quantification in a sample).The differential measurements discriminate a Faraday current from a capacitive one. In this technique, theapplied waveform is the sum of a pulse train and a staircase from the initial potential to a limit potential,or to the final potential if the scan is reversed. The current is sampled just before the pulse and near theend of the pulse. The resulting current is the difference between these two currents. It has a relatively flatbaseline. The current peak height is directly related to the concentration of the electroactive species in theelectrochemical cell.


- 42 -

OCP will display the current open circuit potential of the cell (update every second). If theinstrument is turned off, this value will display “Not Available”.

DPV curve in K3Fe(CN)6 system


7.5.2 Scan ParametersIn Differential Pulse Voltammetry (DPV), the base potential is incremented from Init E

toward Final E. A potential pulse is applied. Current is sampled before and at the end of thepotential pulse. The difference between these two current samples is recorded as a function ofpotential.

Initial E and Final E should be at least 0.01 V apart.


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A potential can be specified in several ways. If “vs. OCP” is chosen, the specified potentialis added to the open circuit potential of the cell. “vs. RE” is used to select an exact potential.

Inc.E is the increment potential of each pulse; it can be chosen from 0.001V to 0.05V.Amplitude can be chosen from 0.001V to 0.5V.Pulse Width can be chosen from 0.001s to 10s.Pulse Period can be chosen from 0.01s to 50s.



CorrView can be later used to display the data in any of the other formats.7.5.5 Pstat/Gstat(ECS)


See Cell Setting 3.2.7.6 Normal Pulse Voltammetry

Experiments→Voltammetry→Normal Pulse Voltammetry

In Normal pulse voltammetry, the basic potential is maintained at the initial potential.Applying a series of amplitude-increasing pulse waves, the current is sampled at the end of thepotential pulse. The current is recorded in the form of a pulse voltammetric function.

In NPV, pulses of increasing amplitude are applied. The pulses always start from the initialpotential. The current response is usually sampled at the end of the pulse and then plotted versuspulse potential. In such a way a discrete, digitized curve is obtained. The initial potential is avery important parameter. It determines the electrode surface state before the Faraday currentstarts to flow. The measurement of the current at the end of the pulse allows for a substantialelimination of the charging current and leads to exposition of the Faraday current of interest.


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7.6.2 Scan ParametersIn Normal Pulse Voltammetry (NPV), the base potential is held at Init E, and a sequence of

potential pulses with increasing amplitude is applied. The current at the end of each potentialpulse is sampled and recorded as a function of the pulse potential.

Init E and Final E should be at least 0.01V apart. “vs.RE” is used to select an exact potentialto be applied.


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Inc.E is the increment potential of each pulse; it can be chosen from 0.001V to 0.05V.Pulse Width can be chosen from 0.001s to 10s.Pulse Period can be chosen from 0.01s to 50s.



CorrView can be later used to display the data in any of the other formats.7.6.5 Pstat/Gstat(ECS)


See Cell Setting 3.2.7.7 Differential Normal Pulse Voltammetry

Experiments→Voltammetry→Differential Normal Pulse VoltammetryThis is a hybrid of differential pulse and normal pulse voltammetry. Similar to the normal

pulse method, in this case a pulse will be superimposed on a base potential. On top of this pulse amodulation step with definable amplitude and duration is applied. The current just before and atthe end of the modulation step will be measured and the difference will be stored. In this manner,the advantages of normal pulse (short electrolysis time) are combined with those of differentialpulse (pronounced Faraday currents).


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7.7.2 Scan ParametersIn Differential Normal Pulse Voltammetry (DNPV), the base potential is held at Init E, and a

sequence of dual potential pulses is applied. The magnitude of the first pulse increments afterevery iteration, and the second pulse has a constant amplitude relative to the first. Current issampled at the end of both potential pulses, and the difference of these two values is recorded asa function of the first pulse potential.

Init E and Final E should be at least 0.01V apart. “vs.RE” is used to select an exact


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potential to be applied.Inc.E is the increment potential of each pulse; it can be chosen from 0.001V to 0.05V.Amplitude can be chosen from 0.001V to 0.5V.1st Pulse Width can be chosen from 0.001s to 10s.2nd Pulse Width can be chosen from 0.001s to 10s.Pulse Period can be chosen from 0.05s to 50s.





See Cell Setting 3.2.7.8 A.C. Voltammetry

Experiments→Voltammetry→A.C. VoltammetryIn A.C. Voltammetry, the base potential is incremented from Init E to Final E, and a

sequential sine waveform is superimposed. Current is sampled when the AC signal is applied,and it is analyzed by using a software lock-in amplifier. During the experiment, only the absoluteAC current is displayed. After the experiment, the phase-selective current at any phase angle willalso be available for display.


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Initial E(V) -10~+10 Initial potential

Final E(V) -10~+10 Final potential of the experiment

Inc. E(V) 0.001~0.05 Potential difference between two adjacent waves

Amplitude(mV) 0.001~0.5 AC amplitude of each waveform

AC frequency(Hz) 0.1~10000 Frequency of the AC power

Bias DC current Superimposed DC bias current in AC signal

Sample period(s) 0.1~50 Time width of the samplingInitial E and Final E should be at least 0.01V apart.Inc. E is the increment potential of each pulse; it can be chosen from 0.001V to 0.05V.Amplitude can be chosen from 0.001V to 0.5V.When the AC frequency is 2Hz or lower, the Sample Period parameter should be at least 2

seconds.Bias DC Current, check off or on, enables DC current bias during run.



CorrView can be later used to display the data in other formats.


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7.8.5 Pstat/Gstat(ECS)See 3.1 Pstat/Gstat(ECS) Setting.


7.9 2nd Harmonic A.C. Voltammetry

Experiments→Voltammetry→2nd Harmonic A.C. VoltammetryIn Second Harmonic AC Voltammetry, the base potential is incremented from Initial E

toward Final E, and a sequential sine waveform is superimposed. Current is sampled when theAC signal is applied, and its second harmonic component is analyzed by using a software lock-inamplifier. During the experiment, only the absolute second harmonic AC current is displayed.After the experiment, the second harmonic current at any phase angle will also be available fordisplay.





Final E(V) -10~+10 Final potential of the experiment

Inc. E(V) 0.001~0.05 Potential difference between two adjacent waves

Amplitude(mV) 0.001~0.5 AC amplitude of each waveform


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AC frequency(Hz) 0.1~10000 Frequency of the AC power

Bias DC current Superimposed DC bias current in AC signal

Sample period(s) 0.1~50 Time width of the sampling

Init E and Final E should be at least 0.01 V apart.Inc. E is the increment potential of each pulse; it can be chosen from 0.001 V to 0.05 V.Amplitude can be chosen from 0.001 V to 0.5 V.When the AC frequency is 2 Hz of lower, the Sample Period parameter should be at least

2seconds.Bias DC Current, check off or on, enables DC current bias during run.





See Cell Setting 3.2.7.10 Fourier TransformAC Voltammetry (FTACV)

Experiments→Voltammetry→Fourier Transform AC VoltammetryFor FTACV, the way of testing, parameters setting and data acquisition is the same as ACV.

The difference lies in post-processing of the data. After the test, the software will automaticallydo the Fourier conversion with the original data, meanwhile obtaining the 2nd, 3rd, 4th, 5th, and6th harmonics ACV data.


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Parameter setting window for FTACV

7.10.1 Experiment parametersParameter Range Description


Final E (V) -10~+10 Final potential

Inc. E (V) 0.001~0.05Potential difference between adjacent waves

Amplitude (mV) 0.001~0.5AC amplitude for every wave

AC frequency(Hz) 0.1~10000AC frequency

Bias DC currentSuperimposed bias DC current in AC signal

Sample period (s) 0.1~50Time of sampling

Initial E and Final E should be at least 0.01 V apart.For parameter of Bias DC current, the user can choose one among Off, Below 1Hz, Below

100Hz, On.




8. Amperometric8.1 Differential Pulse Amperometry (DPA)

Experiments→Amperometric→Differential Pulse Amperometry (DPA)In Differential Pulse Amperometry (DPA), a conditioning potential can be applied for

electrode conditioning, during which current is not sampled. Two potential pulses are appliedafter the conditioning step, and the current at the end of each pulse is recorded as a function oftime.


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Parameter setting window for DPA

8.1.1 Experiment parametersParameters Range Description

Initial E(V) -10~10 The initial potential of the experiment

Initial Pulse Width (s) ≥0 The duration of the initial potential. The current is notsampled.

Conditioning E(V) -10~10 The electrode conditioning potential

Time(s) ≥0 The duration of the conditioning potential. The current is notsampled.

1st pulse potential(V) -10~10 The 1st pulse potential in each cycle.

1st Pulse Width (s) 0.01~100 The duration of the 1st pulse potential in each cycle. Thecurrent is sampled.

2nd Pulse Potential (V) -10~10 The 2nd pulse potential in each cycle.

2nd Pulse Width (s) 0.01~100 The duration of the 2nd pulse potential in each cycle. Thecurrent is sampled.

Cycles 10~100000 The total number of cycling.

Sample width(ms) 1~ durationtime*0.5

The sampling width of the 1st pulse potential and 2nd pulsepotential in each pulse.

Line Freq. 1~durationtime*0.025

A line frequency cycle is 20ms.The integration cycle cannot be bigger than half the durationof the pulse. Either sample width or Line Freq.should bechecked.


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8.2 Double Differential Pulse Amperometry (DDPA)

Experiments→Amperometric→Double Differential Pulse Amperometry(DDPA)Double Differential Pulse Amperometry (DDPA) alternates between two instances of

differential pulse amperometry, with two sets of data recorded and displayed. In each instance, aconditioning potential applied for electrode conditioning, during which current is not sampled.Two potential pulses are applied after the conditioning step, and the current at the end of eachpulse is recorded as a function of time.

Parameter setting window for DDPA


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8.2.1 Experiment parametersParameter Range Description


Initial Pulse Width (s) ≥0 The duration of the initial potential. The current is notsampled.

1st Conditioning E(V) -10~10 the 1st cleaning potential of the experiment

1st Conditioning T(s) ≥0 The duration of the 1st conditioning potential. In thisprocess the current is not sampled

1st pulse potential(V) -10~10 the 1st pulse potential in each cycle

1st pulse width(s) 0.01~100 The duration of the 1st pulse potential in each cycle. Thecurrent is sampled.

2nd pulse potential(V) -10~10 The 2nd pulse potential in each cycle

2nd pulse width(s) 0.01~100 The duration of the 2nd pulse potential in each cycle. Thecurrent is sampled.

2nd Conditioning E(V) -10~10 the 2nd cleaning potential of the experiment

2nd Conditioning T(s) ≥0 The duration of the 2nd cleaning potential. In this processthe current is not sampled

3rd pulse potential(V) -10~10 the 3rd pulse potential in each cycle

3rd pulse width (s) 0.01~100 The duration of the 3rd pulse potential in each cycle. Thecurrent is sampled.

4th pulse potential(V) -10~10 The 4th pulse potential in each cycle

4th pulse width(s) 0.01~100 The duration of the 4th pulse potential in each cycle. Thecurrent is sampled in this process.

Cycles 10-100000 Total number of cycling

Sample width(ms) 1~durationtime*0.5

The sampling width of pulse potential 1,2,3,4

Line Freq. 1~pulsedurationtime*0.025

A line frequency cycle is 20ms.The integration cycle cannot be higher than half of theduration of the pulse. Either sample width or Line Freq.is checked.




8.3 Triple Pulse Amperometry (TPA)

Experiments→Amperometry→Triple Pulse Amperometry (TPA)In Triple Pulse Amperometry (TPA), three potential pulses are applied. The first two pulses

are for electrode conditioning. Current is sampled at the end of the third potential pulse andrecorded as a function of time. The third potential pulse can be constant or incremented after


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each cycle.

8.3.1 Experiment parameters

Parameter setting window for TPA

Parameter Range Description


Initial Pulse Width (s) ≥0 The duration of the initial potential. The currentis not sampled.


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Final E(V) -10~10 The final potential of the experiment.

1st pulse E(V) -10~10 the 1st pulse potential in each cycle

1st pulse width(s) 0~100 The duration of the 1st pulse potential in eachcycle.

2nd pulse E(V) -10~10 The 2nd pulse potential in each cycle

2nd pulse width(s) 0~100 The duration of the 2nd pulse potential in eachcycle.

3rd pulse E(V) -10~10 the 3rd pulse potential in each cycle

3rd pulse width(s) 0.001~100 The duration of the 3rd pulse potential in eachcycle. The current is sampled.

Pulse inc. E(V) 0~0.02 increment potential for third step


Sample width(ms) 1~3rd pulsepotentialduration*0.5

The sampling width of the 3rd pulse potential ineach cycle

Line Freq. 1~3rd pulsepotentialduration*0.025

A line frequency cycle is 20ms.The integration cycle cannot be higher than halfof the 3rd pulse potential duration. Either samplewidth or Line Freq. should be checked.




8.4 Integrated Pulse Amperometric Detection(IPAD)

Experiments→Amperometric→Integrated Pulse Amperometric Detection(IPAD)In Integrated Pulse Amperometric Detection (IPAD), six segments of potential sweeps or

steps are applied. Current is sampled and integrated during the first four segments. Electrodeconditioning or cleaning occurs during the last two steps. The integrated current is averaged andrecorded as a function of time.


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8.4.1 Experiment parameters

Parameter setting window for IPAD



Initial pulse width(s) ≥0 Initial potential duration( current integration for thelast 10 ms)

Peak E(V) -5~5 Potential is scanned Initial E to Peak E

1st scan time(s) 0.1~1 Scan time from Initial E to peak E;The current is sampled and integrated.

Return E(V) -5~5 Return potential in each cycle


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2nd scan time(s) 0.1~1 Scan time from peak E to Return E;The current is sampled and integrated.

Hold E(V) -5~5 Hold potential of each cycle

Hold Time(s) 0.05~1 Hold potential duration (current integration for thefirst 10 ms)

Oxd. E(V) -5~5 Oxidation potential for electrode treatment

Oxd. Time(s) 0.05~1 Oxidation time durationThe current is not sampled

Red. E(V) -5~5 Reduction potential for electrode treatment

Red. Time(s) 0.05~1 Reduction time durationThe current is not sampled





9. Stripping Voltammetry9.1 Potentiostatic Stripping

Experiments→Stripping Voltammetry→Potentiostatic StrippingIn stripping voltammetry, the usual working electrode is a dropping (or a film) mercury and

the most common technique is the anodic stripping, meaning that a negative potential is appliedto the electrode and the cations are discharged as metallic atoms into the mercury (amalgam).Successively, the metal atoms are oxidized again during an anodic scanning of potential. Duringthe scanning of the potential, the current is measured and plotted, so the resulting voltammogramis a peak shaped graphic.

Stripping voltammetry in a solution containing Pb2+, Cd2+, Cu2+


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Conditioning E(V) -10~10 Cleaning potential

Conditioning T(s) ≥0 Cleaning potential duration; the current is not sampled

Deposition E(V) -10~10 Deposition potential is usually 0.3~0.5V(or more) lower thanthe standard redox potential, which makes it easy for the testedmetal ions to be reduced.

Deposition Time(s) >0 The time of the deposition process

Quiet Time(s) >0 Waiting time after deposition and before stripping

Stripping E(V) -10~10 the potential in the stripping;

It’s usually equal to or higher than the oxidation potential of thetested ion.

Deposition Time >0 the time of the potentiostatic stripping process


9.1.2 Deposition ParametersBefore the experiment, the surface of working electrode needs cleaning by this conditioning

step.A constant potential deposition step is applied to accumulate species on the working


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electrode surface. This potential can be specified to choose either “vs. OCP” or “vs. RE”.The deposition time determines how long the potential will be held at this step. After

deposition, the experiment can be quiet for some time.9.1.3 Potentiostatic Stripping Parameters

After the constant potential deposition step is applied, the species accumulated on theelectrode surface are stripped out by applying a constant potential.

This stripping potential can be specified in several ways. If “vs. OCP” is chosen, thespecified potential is added to the open circuit potential of the cell.“vs.RE” is used to select anexact potential.9.1.4 Data Acquisition

If Frequency(Hz) is chosen, the acquisition rate in Points/Second is specified.9.1.5 Axis Type:



See Cell Setting 3.2.9.2 Linear Stripping Voltammetry

Experiments→Stripping Voltammetry→Linear StrippingVoltammetry stripping technique is a high-sensitivity method for determination of trace

elements. If using hanging mercury electrode to replace the dropping mercury electrode used ingeneral polarography, the polarographic wave that is used for quantitative measurements can alsobe obtained.

Normally the mercury electrode is the cathodic pole and reduction reaction occurs:Cd +2e+Hg─→Cd (Hg)Cd(Hg)─→Cd +2e+Hg

If the potential of the hanging mercury electrode is fixed at E' (approximately -1V vs. SCE),amalgam will be generated after Cd is reduced on the electrode. After a period of electrolysis, theconcentration of Cd in Hg reaches to a certain level. After deposition time that is set, CSpotentiostat will automatically let the polarization voltage of hanging mercury electrode varyfrom -1V(vs. SCE) towards the positive, and the potential changes from -1V to 0, thus gettingthe Cd oxidation wave. The reaction is as follows:

Cd (Hg)─→Cd +2e+Hg

The metal Cd is “stripped” from the electrode, and oxidized to be Cd2+and goes to thesolution. Because in the process of stripping, hanging mercury electrode is the anodic pole, andthat the polarization electrode is non-renewed hanging mercury electrode, mercury film electrode,or glass carbon mercury electrode, instead of dropping mercury electrode, this technique is alsocalled anodic voltammetry stripping.


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Parameter Range Description

Conditioning E(V) -10~10 Cleaning potential

Conditioning T(s) ≥0 Cleaning potential duration; the current is notsampled

Deposition E(V) -10~10 Deposition potential is usually 0.3~0.5V(or more)lower than the standard redox potential, whichmakes it easy for the tested metal ions to bereduced.

DepositionTime(s)

>0 The time of the deposition process

Quiet Time(s) >0 Waiting time after deposition and before stripping

Initial E(V) -10~10 Initial potential of stripping

Final E(V) -10~10 Final potential of stripping

Scan rate 0.01~1000mV/s Scan rate in stripping process


9.2.2 Deposition ParametersBefore the experiment, the surface of working electrode needs cleaning by this conditioning

step.A constant potential deposition step is applied to accumulate species on the working


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electrode surface. This potential can be specified to choose either “vs. OCP” or “vs. RE”.The deposition time determines how long the potential will be held at this step. After

deposition, the experiment can be quiet for some time.9.2.3 Linear Stripping Parameters

In Linear Stripping, a constant potential deposition step is first applied. After that, thespecies accumulated on the electrode surface are stripped out by applying a linear potential,which is scanned from an initial potential to a final potential that progresses at a defined scanrate.

A potential can be specified in several ways. If “vs. OCP” is chosen, the specified potentialis added to the open circuit potential of the cell. “vs.RE” is used to select an exact potential.9.2.4 Data Acquisition




See Cell Setting 3.2.9.3 Staircase Stripping Voltammetry

Experiments→Stripping Voltammetry→Staircase Stripping

In staircase stripping, the potential applied on working electrode is varied in mode of linearstaircase. It is similar to linear stripping in testing speed. Staircase stripping is considered to be anumerical version of linear sweep stripping.


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See 4.1.1 File Name.9.3.2 Staircase Stripping Parameters

Before the experiment, the surface of working electrode needs cleaning by this conditioningstep.

A constant potential deposition step is applied to accumulate species on the workingelectrode surface. This potential can be specified to choose either “vs. OCP” or “vs. RE”.

The deposition time determines how long the potential will be held at this step. Afterdeposition, the experiment can be quiet for some time.

In Staircase Stripping, a constant potential deposition step is applied. After that the speciesaccumulated on the electrode surface are stripped out by applying a staircase potential, which isincremented from Initial E toward Final E that progresses at a defined increment.9.3.3 Data Acquisition




See Cell Setting 3.2.9.4 Square wave stripping Voltammetry

Experiments→Stripping Voltammetry→Square Wave Stripping

For square wave stripping voltammetry, the potential applied on the working electrode is asquare-wave linear mode in stripping process. Square wave stripping voltammetry appliessubstantial differential technique, and the waveform of potential that is applied on the workingelectrode is composed of a symmetric square wave being superimposed on a base step potential.Excellent sensitivity and fast scanning ability are the advantages of square wave strippingvoltammetry, which reduces the analysis time.


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See 4.1.1 File Name.9.4.2 Deposition Parameters

Conditioning potential: Before deposition, the conditioning potential is applied on workingelectrode in order to remove impurities, and automatically update working electrode surfacestate.

Duration: It is a separate time value that specifies the length of time when that conditioningpotential is applied.

Deposition potential: deposition potential is generally lower than the standard redox.potential by 0.3V~ 0.5V. Metal ions which will be measured are easily reduced.

Deposition time: It is a separate time value that specifies the length of time when thatdeposition potential is applied.

Quiet time: When stopping stirring, potential is not applied on the working electrode.9.4.3 Square wave stripping Parameters

Initial potential: the minimum potential for dissolution process to begin.Final potential: final potential is generally higher than the oxidation potential of analyte ions.Increment potential: the incremental potential of each step.Amplitude: square wave amplitude, half peak-to-peak.Frequency: square wave pulse frequency.A potential can be specified in several ways. If “vs. OCP” is chosen, the specified potential

is added to the open circuit potential of the cell. For example, “0.1V vs. OCP” means applying apotential 0.1 Volts above the open circuit potential. “vs.RE” is used to select an exact potential.9.4.4 Data Acquisition

If Frequency(Hz) is chosen, the acquisition rate in Points/Second is specified.


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See Cell Setting 3.2.9.5 Differential Pulse Stripping Voltammetry

Experiments→Stripping Voltammetry→Differential Pulse Voltammetry Stripping


See 4.1.1 File Name.9.5.2 Data Acquisition




See Cell Setting 3.2.9.6 Normal Pulse Stripping Voltammetry


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Experiments→Stripping Voltammetry→Normal Pulse Voltammetry Stripping


See 4.1.1 File Name.9.6.2 Data Acquisition




See Cell Setting 3.2.9.7 Differential Normal Pulse Stripping Voltammetry

Experiments→Stripping Voltammetry→Differential Normal Pulse Voltammetry Stripping


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Data AcquisitionIf Frequency(Hz) is chosen, the acquisition rate in Points/Second is specified.




See Cell Setting 3.2.10. Impedance(EIS)

CS350 series use dual signal correlation integral system to improve accuracy. The frequencyrange is 10μHz~1MHz. The user can automatically do impedance measurement under opencircuit potential or any DC bias. Built-in DC offset eliminating circuit can effectively improvemeasurement accuracy of the AC signal. The amplitude of the excitation sine wave can be setarbitrarily from 0 ~ 2.5V.AC impedance measurement includes the following three methods:①EIS ~ frequency sweep curve: it measures impedance spectroscopy of the system at differentfrequencies. It’s the most commonly used method to measure impedance with Nyquist and Bodeplots.


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②EIS~ time scan curve: it measures impedance of the system as a function of time at a singlefrequency. It is used to track the dynamic process of some systems such as conductivity.③EIS ~ potential sweep curve: it measures impedance of the system with the change of DCpolarization potential at a single frequency. It can be used to measure the differential capacitancecurve and zero charge potential, etc.10.1 EIS vs Frequency(IMP)

Experiments→Impedance→EIS vs. Frequency

The method of EIS vs Frequency is to measure the impedance spectroscopy of theelectrochemical system in difference frequency. Nyquist and Bode plot is obtained.

OCP will display the current open circuit potential of the electrolytic cell (update everysecond). It is useful for the users to judge whether the working electrode is stable for impedancetest.10.1.1 File Name

The user should enter a file name to save data before starting the test. At the first time, whenYou input a name and click OK, you will see the default data storage path on the top of thetesting window. Or you can click the Browse, and choose the storage path as you want. This isparticularly useful if you forget the file names that you already use. Once you choose the path, itwill be the default storage path of the following data files unless you click “Browse” and chooseanother path again.

CS Studio will automatically append the suffix “.z60” to a file name. So if you input“tutor1”, the name of the data file will be shown as “tutor1.z60”.

The info in the Comments box will be saved in the data file. You can input info. such asthe medium, the solution content, etc. Other info. such as the time when you perform the test,and all the related measurement parameters will be automatically saved in the data file. You don’tneed to enter such information into comments.10.1.2 Polarization

“DC potential” is the setting DC polarization potential of the working electrode duringimpedance test. If the test needs to proceed under open circuit potential (OCP), then the user can


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enter “0” and select “vs. OCP” in the drop-down box. At this moment the potentiostat willautomatically give an output of the sum of OCP and the DC potential to the working electrode. Ifyou need to do the impedance test under 50mV DC potential of anodic polarization, you canenter “0.05V” here.

If the test needs to be carried out at a certain potential (such as-0.5V vs. SCE), you can select“vs. RE electrode” in the drop-down box and enter “-0.5V”.The potentiostat will polarize theworking electrode to be “-0.5V”.

AC amplitude is the amplitude of the excitation signal of electrochemical impedance. Forexample, E = 0.012 sin (wt) V means AC signal amplitude is 12mV. Under high frequency, theactual polarization amplitude of the working electrode may be lower than this value due to ratelimitation of the amplifier and high-frequency transmission loss of the conducting wires.10.1.3 Frequency Sweep

Users should decide the mode of frequency sweep. Frequency sweep starts from the initialfrequency to the final frequency, and the mode can be both linear and logarithmic. If you chooselinear mode, the frequency measured points will be evenly distributed between the initialfrequency and final frequency. If the frequency range is from “1k to 1Hz”, and you set 10measured points, the measured frequencies will be “1Hz, 99.9Hz, 2×99.9 Hz ...” Generallyspeaking, you don’t use this mode except for special requirements.

If the mode is logarithmic, the sampled frequency data points will be evenly distributed infrequency logarithmic axis (Bode plot). It is particularly useful when frequency range is between2 to 5 orders of magnitude. If the frequency range is from“1k to 10Hz”, and you set 5 measuredpoints for every 10 octaves, the measured frequencies will be 10 × 100Hz, 10 × 100.2Hz, 10 ×100.4Hz, 10 × 100.6Hz, 10 × 100.8Hz, 10 × 101.0Hz.This mode is usually selected.10.1.4 Pstat/Gstat(ECS)

Click on this button, and open the window for instrument setting. You can choose theinstrument model, set the switching way of current range, signal gain/loss, ground mode, filterbandwidth, digital smoothing, quiet time (scan delay). For regular electrochemical impedancemeasurement system, real ground mode is recommended, and 2.2pF~1μF is OK for filterbandwidth.10.1.5 Cell Setting

It allows the user to enter related information regarding work electrode and electrolytic cell,such as surface area of the electrode, material, and temperature etc. These parameters don’t affectthe raw data and will be automatically saved in the File Name so that the user can recognize themeasuring conditions in the future. Meanwhile, this information is needed for corrosion ratecomputation.


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10.1.6 Analyzer Setting

Current rangeThe user can choose current range automatically/manually. If select “auto”, you need to set athreshold for high-frequency current range to limit the min.current range the potentiostat can useduring high frequency measurements. When the measured frequency is higher than 1000Hz, theautomatic range will be no less than 2mA. The definition of high frequency is made by the user.The figure above shows that fH>5000Hz is high frequencies, fL<5Hz is low frequency, and5Hz~5000Hz is middle range.

The impedance of the working electrode at high and low frequency signal are different. Toimprove accuracy for measurement results, the setting for current range is varied. The user canselect different “current range” according to frequency band. In general, current range at lowfrequency should be lower than that at high frequency. If the user sets current rangeinappropriately, the impedance spectroscopy curve may have large noise. Or if the current rangeis too frequently changed, there will be obvious turning points in the curve. In such cases, theuser should re-set. By observing signal amplitude of the waveform displayed, users can judge ifthe current range setting is appropriate.

Bandwidth SettingBandwidth is set to change the frequency response bandwidth of potentiostat. When the

capacitance value is higher, the bandwidth of the potentiostat will be narrower, and thehigh-frequency performance will weaken, but stability will be improved. Bandwidth is set basedon the critical frequency fc. If measured frequency is higher than fc, you should choose a smallercapacitance (or turn it off), then there will not be false impedance spectra at high frequency area.But for high impedance system, it may result in oscillation. You may have to increase thecapacitance. To check if a shock appears, you can observe the amplitude of signal and the waveform.

When the measured frequency is lower than fc, you should select the second-gradecapacitance, and its value should be no less than that of the first grade and the instrument has alow bandwidth. When f> 10Hz, bandwidth setting capacitance is 22pF; when f <= 10Hz, it is100pF.

For system of lowresistance, you canchoose 2mA. For highresistance system(e.g.coating), you can choose20μA~200μA. If therange is not properlyselected, noise mayappear on the EIS curve.

For stable system, youcan choose off in thedrop-down list. Forsystem of highresistance(e.g. coating),you should choose22~100pFto reduce thenoise of themeasurement curve. Butthere may be a littleadditional capacitor ringin high frequencysection of the impedancespectroscopy.


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DC Bias CompensationDC bias compensation is used to eliminate DC level which is superimposed on the

potentiostat or the current output signal and increase the AC magnification of potential or currentsignals, and thus increase impedance measurement accuracy. CS350 instrument automaticallyuses internal bias elimination of potential and current, and therefore impedance measurementaccuracy is improved. During impedance measurement, you are recommended to at least choosethe “bias compensation” option. If the amplitude of AC excitation signal is less than 100mV, youcan choose “AC enhancement” option.

Integration TimeIncreasing the integration time can improve the impedance measurement accuracy, and

reduce the impact of noise on the result. Integration time can be set to be the number of cycles ortime (in second). The integration time represents time cost at each frequency point. The longerthe integration time is, the higher the measurement accuracy will be, and the more time it takes.

Delay time is the waiting time between measurements of two frequency points. Before themeasurement of the next point, the internal frequency analyzer will wait for a period of time,allowing electrode to come to the state of balance. The delay time is usually not needed forelectrochemical system.10.1.7 The impedance spectroscopy fitting

CorrTest uses Zview software as a tool to analyze impedance spectroscopy and drawgraphics. Zview is capable of impedance analysis, and it can make complex plane diagram&Bode plot about data. It allows users to create a variety of equivalent circuits and do data fitting.It has functions of graphic’s local zooming in, curve smoothing, data correction and so on. Zviewcan output the graphics to a printer or clipboard, and you can also paste a graphic into a Worddocument.

Generated impedance File Names (.z60) from CorrTest is fully compatible with Zview.Users can directly click on “Zview Drawing” menu after data acquisition, and import one ormore File Names from the “Documents” → “File Name” menu, and then select from a variety ofgraphics methods in the “Options” → “activities graphics” menu.

If you want to change the graphics’ coordinate text, you can right-click the menu, select“Setting” to modify, and select “Text” to write whatever in the graphics. If you want to changethe color, line pattern, or mark, etc., you can set in the pop-up dialog box of “File” → “FileName” menu.

Equivalent circuit fittingSelecting “Equivalent Circuit” from the tool bar, you can set up equivalent circuit of their

own or just choose the classic equivalent circuit. In the equivalent circuit window, select“Model” → “Edit equivalent circuit”, then you can start simulating or fitting.

Graph copyRight-click the mouse, from the pop-up dialog box, select “copy graphics to the clipboard”,

then in Word, through “Edit” → “Paste”, graphics will be directly pasted into Word document.10.2 EIS vs Time(IMPT)

Experiments→Impedance→EIS vs. Time(IMPT)It measures the impedance characteristics of the electrochemical system as a function of

time at a fixed frequency. This method is used to track the dynamic processes of some systems,such as conductivity.


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OCP will display the current open circuit potential of the electrolytic cell (update everysecond). This is particularly useful for the user to judge whether the working electrode is stablefor impedance test.10.2.1 File Name

See 10.1.1 File Name.10.2.2 Polarization

“DC potential” is the setting DC polarization potential of the working electrode duringimpedance test. If the test needs to proceed under open circuit potential (OCP), then the user canenter “0” and select “vs. OCP” in the drop-down box. At this moment the potentiostat willautomatically give an output of the sum of OCP and the DC potential to the working electrode. Ifyou need to do the impedance test under 50mV DC potential of anodic polarization, you canenter “0.05V” here.

If the test needs to be carried out at a certain potential (such as-0.5V vs. SCE), you can select“vs. RE” in the drop-down box and enter “-0.5V”.The potentiostat will polarize the workingelectrode to be “-0.5V”.

AC amplitude is the amplitude of the excitation signal of electrochemical impedance. Forexample, E = 0.012 sin (wt) V means AC signal amplitude is 12mV. Under high frequency, theactual polarization amplitude of the working electrode may be lower than this value due to ratelimitation of the amplifier and high-frequency transmission loss of the conducting wires.10.2.3 Time Scan

In Impedance ~ Time scan, frequency of sine wave is constant. It measures the impedance ofsome electrochemical systems at a frequency point as a function of time.

Interval - time interval for measurement at each frequency point.Total time- the total time of measurement.

10.2.4 Pstat/Gstat(ECS)Click on this button, and open the window for instrument setting. You can choose the

instrument model, set the switching way of current range, signal gain/loss, ground mode, filter


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bandwidth, digital smoothing, quiet time (scan delay). For regular electrochemical impedancemeasurement system, real ground mode is recommended, and 2.2pF~1μF is OK for filterbandwidth.10.2.5 Cell Setting

It allows the user to enter related information regarding work electrode and electrolytic cell,such as surface area of the electrode, material, and temperature etc. These parameters don’t affectthe raw data and will be automatically saved in the File Name so that the user can recognize themeasuring conditions in the future. Meanwhile, this information is needed for corrosion ratecomputation.10.3 EIS vs Potential(IMPE)

Experiments→Impedance→EIS vs. PotentialThis method is used to measure single-frequency impedance at different DC polarization

potential. The potential is stepped from the “initial potential” to “final potential”. It is mainlyused for Mott-Schottky (M-S) plot. M-S plot has been widely used to study the semiconductor ofpassivation film on the surface of the metal. It can determine the carrier’s type, concentration andthe flat band potential.

When the passivation film is in contact with the solution and the space charge of thesemiconductor passivation film is in the state of depletion (remove majority carriers from thespace charge region and minority carriers don’t exist), for the space charge capacitance (Csc) andthe measured voltage (Vm), there is the following linear equation:

Where, Vfb is flat band potential, Nd and Na are donor and accepter carrier concentration, εis the relative permittivity, ε0 is the permittivity of vacuum, A the electrode surface area, k isBoltaman constant, T is absolute temperature, e is the electric charge.

Passivation film has a double layer structure. Because the composition and the crystalstructure are different for the inner and outer layer of the passivation film, semiconductor type isalso different for the two layers. Two space charge layers are thus formed inside the passivationfilm, that is, the solution/passivation film interface space charge layer and the inner layer /outerlayer interface pn junction capacitance. Because both pn and passivation film capacitance aresmall, in the impedance ~ potential sweep, high-frequency sine wave is generally used formeasurement.


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OCP will display the actual open circuit potential of the electrolytic cell (update everysecond). This is particularly useful for the user to determine whether the working electrode isstable for impedance test.10.3.1 File Name

See 10.1.1 File Name.10.3.2 EIS Parameters

Frequency and AC Amplitude specify the frequency and amplitude of sine wave during theimpedance measurement.10.3.3 Potential Parameters

Initial potential—it is set as the initial DC level of the working electrode in impedance ~potential sweep. You can choose potential applying means, thereby changing the referencepotential of all the polarization potential set points.

Final potential — it is the stop potential set in impedance ~ potential sweep.Potential incremental—it is increased with the form of steps; users can do single-frequency

impedance measurement at each step potential point.10.3.4 Pstat/Gstat(ECS)

Click on this button, and open the window for instrument setting. You can choose theinstrument model, set the switching way of current range, signal gain/loss, ground mode, filterbandwidth, digital smoothing, quiet time (scan delay). For regular electrochemical impedancemeasurement system, real ground mode is recommended, and 10pF~100pF is OK for filterbandwidth.10.3.5 Cell Setting

It allows the user to enter related information regarding work electrode and electrolytic cell,such as surface area of the electrode, material, and temperature etc. These parameters don’t affectthe raw data and will be automatically saved in the File Name so that the user can recognize themeasuring conditions in the future. Meanwhile, this information is needed for corrosion ratecomputation.


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11. Charging/Discharging11.1 Battery Charging/Discharging

Experiments→Charging/Discharging→Battery Charging/DischargingIt is used to test the charge and discharge characteristics of rechargeable battery and its

lifetime.


11.1.2 ExperimentCharge Current— because of different connecting ways of the electrodes, the charge current

sign will be different. If the working electrode is connected to battery positive, and the reference& counter electrodes are connected to the battery negative, the displayed open circuit potentialwill be positive. Then enter a positive value and it indicates charge.

E Threshold for C-V Conv.— it’s the critical voltage when charge process is changed fromconstant current mode to constant voltage mode. According to the charge rules, constant currentcharge mode is generally adopted in the early stage of charge. When the battery voltage is higherthan the critical voltage, it will turn into constant voltage mode. At this moment the chargecurrent will gradually decrease with time. When it falls to the trickle current (usually 10 to 20%of the charge current), the software will automatically disconnect the charge circuit.

Discharge current— if the working electrode is connected to battery positive end, and thereference & counter electrode are connected to battery negative end, then enter a negative valuein this input box, it represents the discharge.

Discharge threshold voltage— in discharge process when the voltage drops to this thresholdvoltage, the battery will stop discharge so as not to excessively discharge.

Quiet time— it specifies the interval time from the state of charge to the state of discharge.During this time, the battery is in the open circuit.

Discharge Time


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Maximum charge and discharge time— after a period of time of battery charge (ordischarge), if the specified critical voltage hasn’t been reached yet, the charge (or discharge)process will stop, and turn to discharge (or charge).

Cycles— a complete cycle includes a charging and a discharging process. This parameterspecifies the total number of cycles performed throughout the experiment. When the number isachieved, the experiment will be stopped.

“Time unit” drop-down box— it lets you specify the time unit of charging and discharging.You can select second, minute or hour.

Based on the current value set by the user, the software will automatically select anappropriate current range without users’ setting.11.1.3 Pstat/Gstat(ECS)


See Cell Setting 3.2.11.2 Galvanostatic Charging/Discharging(GCD)

Experiments→Charging/Discharging→Galvanostatic Charging/DischargingIt is used to measure cyclic charge-discharge characteristics of the electrode material (such

as secondary battery or supercapacitor electrode material) under a constant current and test thecycle life of the electrode material. Before starting the test, the “Start” button is inactive. Onlywhen the user specifies a valid file name can the “OK” button be activated. All data afterwardswill be saved in the created file.



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11.2.2 Charge/Discharge CurrentCharging I- if the battery positive is connected to the working electrode, then enter a positive

number, indicating charge.Discharging I- if the battery positive is connected to the working electrode, then enter a

negative number, indicating discharge.11.2.3 Condition for switch of Charging/Discharging

If “based on time” is checked:Charge and discharge time - it specifies the time duration of the process of charge and

discharge. Process of charge will stop and turn to discharge if the time duration reaches the setcharging time, and vice versa.

If “based on E” is checked:If the potential (V) <Ec (vs reference electrode), Ec is set by the user, it means the material

has been fully discharged, the instrument will switch to the charging state. If the potential duringconstant current charging process is higher than Ed (vs. reference electrode), it indicates that forthe material charge process has been completed. Thus it completes a measurement cycle, andwill re-enter the discharge state.

Cycles - a complete cycle includes a charge and a discharge process. It specifies the totalnumber of cycles performed throughout the experiment. When this number is reached, theexperiment will be stopped.

“Time unit” drop-down box -it lets you specify the charge and discharge time unit, you canselect “seconds”, “minute” and “hour.”

For charge-discharge potential, users can select “vs. reference electrode” or “vs. OCP.”11.2.4 Pstat/Gstat(ECS)


See Cell Setting 3.2.12. Bipotentiostat12.1 Hydrogen Diffusion Test (HDT)

Experiments→Bipotentiostat→Hydrogen diffusion TestCS2350 bipotentiostat can do hydrogen diffusion test.Hydrogen Diffusion Test requires a special

set of electrolytic cell (Devnathan-StachurskiCell) which consists of two cells connected inserial (one for galvanostatic hydrogen charging,the other for hydrogen current detection). Ineach cell, there is an independent set ofreference electrode and counter electrode, andthey share a common working electrode. Theworking electrode is a thin metal plate which isclipped between the two cells. (See the right picture).

The square wave cathodic current is applied on the hydrogen charging surface of theworking electrode, and by alternatively changing the current value, the atoms will diffuse intothe metal and gradually reach the detection surface of the working electrode. By measuring theamplitude of the hydroxide current waveform and the lag time, the hydrogen diffusion rate andthe diffusion coefficient can be calculated.

The double electrolytic cell is connected in the way as shown below, add 0.1mol/L NaOH


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solution into the anodic cell. Connect electrodes in anodic cell to the main channel on the frontpanel, and the cathodic cell to the slave channel. Firstly set the anodic polarization potential ofthe main channel’s potentiostat to be 0.2V vs. Hg/HgO, then start the polarization. The anodiccurrent will decline dramatically at the beginning, then slowly to remain a stable value, i.e. theanodic residual current which is generated by the residual hydrogen in the steel sheet or thediffusion surface solution containing some impurities that can be oxidized. When the residualcurrent is lower than the set value, the user can add experimental medium (such as dilutehydrochloricacid) into the cathodic cell, and then start galvanostatic polarization of the slavechannel. The initial current is the peak current (see the figure), e.g. 10mA. At this momenthydrogen ions on surface C of cathodic cell will be reduced to hydrogen atoms, some of whichwill permeate and pass through the metal disc and reach surface A of the anodic cell. Underanodic polarization in the main channel, these hydrogen atoms will be oxidized into ions,forming oxidation current.

Connection diagram for Hydrogen diffusion coefficient test device

Hydrogen charging current curve under control of square wave

Due to hydrogen atoms diffusion rate limits, current at the hydrogen detection side delays,taking the form that anodic current gradually increases (rising edge) or decreases (falling edge)with time. According to the lag time of the hydrogen detection current and its value, thehydrogen concentration in the metal and the diffusion rate can be calculated. And further, somecorrosion inhibitors’ effect on hydrogen diffusion can also be judged.

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12.1.2 Hydrogen Atoms Oxidation (main channel)Potential (V)— it is the polarization potential applied on the working electrode at the

hydrogen current detection side. This potential should ensure the working electrode (thin metaldisk) in anodic polarization. That is, a positive value should be entered to allow hydrogen atomsto be oxidized into ions.12.1.3 Hydrogen Ions Reduction (slave channel)

Please set peak current and valley current of the square wave of hydrogen charging currentas well as their time duration. Hydrogen charging current can only be the cathodic direction sothat the hydrogen atoms are reduced to be ions and pass through the working electrode (metaldisk in the centre). Number of cycles of hydrogen charging current is the number of square wave.

Residual current—With the potentiostatic polarization going on, residual hydrogen currentin the metal will gradually decrease. When it is lower than this set value, the software can starthydrogen charging.

After the measurement begins, potentiostatic polarization will firstly be started in the mainchannel, letting the hydrogen atoms in the metal foil fully diffuse onto the oxidation surface andbe oxidized. It takes a relatively long time. According to ISO, when the residual current is lowerthan 1~2μA/cm²(threshold of residual current) , it can be considered that hydrogen atoms in themetal foil are completely oxidized. Once this oxidation current is lower than the threshold value,the slave channel will start the process of galvanostatic hydrogen charging. Hydrogen chargingcurrent varies between the peak current and the valley current. In general, 10~20 minutes later(depends on the material and thickness of the metal), the anodic current detected in the mainchannel will increase gradually and finally stay stable, as hydrogen atoms diffuse and reach tothe opposite side of the metal sheet and are oxidized to form anodic current.


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CorrView can be later used to display the data in other formats.12.1.6 Main/Slave settings

For bipotentiostat the user needs to set for the “main channel” and “slave channel”respectively. Parameters such as the current range switching, signal gain, low-pass filter, datasmoothing, scan (polarization) delay time etc. can be set same or different. Please note that“ground” mode must be chosen.12.1.7 Cell Setting

See Cell Setting 3.2.12.2 Rotating ring-disk Electrode (RRDE)

Experiments→Bipotentiostat→Rotating ring-disk electrodeCS2350 bipotentiostat can conduct rotating ring-disk electrode.

Compared with the stationary electrode, the rotating disk electrode has the following advantages:stable concentration polarization; good polarization curve stability; being capable of measuringrapid electrochemical reactions. Therefore measuring the polarization curve of the rotating diskelectrode has wide applications, especially in diffusion coefficient calculation, electron gains&losses in reactions, the reactants’ concentration, leveling effect of electroplating additives, andthe kinetic parameters of electrode reactions, etc. With ring electrode, it can also detect reactionintermediates on the disk electrode.

In the figure, DW is disk electrode, and RW is the ring electrode. They are two separateworking electrodes in concentric circles. According to the experimental requirements, DW andRW should be controlled at different polarization potential to ensure that electrochemical producton DW can reach ring electrode for further redox. reactions and be detected.

Disk and ring electrodes are connected to bipotentiostat with dual channels, the mainchannel potentiostat and the slave channel potentiostat whose function is to control the potentialdifference between DW and RW.

Rotating disk electrode (left) and its connection with Bi-Potentiostat (right)


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The main channel applies the common three-electrode mode: CE clamp connects to counterelectrode; RE clamp connects to the reference electrode; and WE clamp connects to the outputwire of disk electrode.

The slave channel uses two-electrode potentiostatic mode: both CE clamp and RE clamp areconnected to the ring electrode, and WE clamp connects to the disk electrode, controlling thepotential difference between RW and DW.

Note: Both the main channel and the slave channel potentiostat need “ground” mode.During the polarization process of the disk electrode, the intermediate product generated on

the disk electrode is further oxidized or reduced after reaching the ring electrode due to thepotential difference between the ring-disk electrodes. Current on the ring electrode is measuredand displayed by slave channel potentiostat.

For RRDE test, the disk electrode is the main working electrode, and the ring electrode ismainly used for monitoring the intermediate product on the disk electrode. Therefore, weconduct the potentiodynamic sweep test, and the potential difference between the ring electrodeand the disk electrode is set to be a constant value, as shown in below parameter settingswindow.

There are mainly two groups of data record. One is the polarization potential/current Ed/Idof the main channel (disk electrode), the other is the polarization potential(fixed value Er) andpolarization current of the slave channel (ring electrode).

parameters setting for rotating ring-disk electrode test


12.2.2 Disk electrode scanning parametersSimilar to potentiodynamic scan, a maximum of 4 independent polarization potentials can be

set on disk electrode.


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12.2.3 Ring electrode polarization parameterPolarization potential —polarization potential of ring electrode vs. the disk electrode, with

unit of V/s.12.2.4 Data Acquisition


When the experiment is performed, the data will be displayed as specified by the Axis Type.CorrView can be later used to display the data in other formats.12.2.6 Main/Slave settings

For bipotentiostat, users need to do settings for the main & slave channel respectively (referto contents of 5.2 in this manual). Please note real filed / ground mode must be chosen.12.2.7 Cell Setting

See Cell Setting 3.2.

13. Misc.Techniques13.1 Electrochemical Noise (EN)

Experiments→Misc.Techniques→Electrochemical NoiseThis method is mainly used to monitor noise

potential and the noise current (zero resistancecurrent or galvanic current) as a function of time.Monitoring duration can be set as you wish.

For CS series electrochemical workstation,the noise signal (or the galvanic current)measurement is different from other methodsbecause it does not require polarization state. Inthe noise/galvanic current measurement, theworking (galvanic) electrodeⅠis connected to thegreen clip of the electrode cable, and working(galvanic) ElectrodeⅡ is connected to the blackclip of GND cable, and the reference electrode isconnected to the yellow clip. (See the figure.)

Run the CS Studio software, select electrochemical noise measurement, and at this time thesoftware window will appear coupling potential (mixed potential) and galvanic current. If thecurrent value is positive, it means the working /galvanic electrodeⅠis anodic and the working(galvanic)Ⅱ is cathodic. The current is flowing from electrodeⅠto electrodeⅡ. A negativecurrent is the opposite.

During measurement, the potentiostat will automatically switch the range according to thecurrent.


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Please pay special attention that you should choose “virtual” for the ground mode.Otherwise ZRA cannot be used to measure galvanic current.13.1.5 Cell Setting

See Cell Setting 3.2.13.2 Data Logger

Experiments→Misc.Techniques→Data LoggerThe data logger is used to synchronously record external signal. A maximum of six external

signals can be recorded simultaneously. (Two channels have already been used for internalelectrochemical measurement). This method is completely independent from otherelectrochemical tests. That is to say there is no interaction between potentiostat’s work andexternal signal recording. Before the test, the “Start” button is inactive. Only when the userspecifies a valid file name will it be activated. All data afterwards will be saved in the createdfile.


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13.2.2 Data AcquisitionInterval - it specifies the time it takes to acquire one sampling point.Frequency - it specifies sampling rate. 1Hz means a sampling point is acquired per second.

10Hz means 10 sampling points is acquired per second.13.2.3 Sampling Data

External gain - It shows the value of channels at present. The external Gain is theamplification of external signals. For example, if the external signal is expected to amplify fivetimes, then enter “5” here.

All external signals are recorded in the form of potential. The user has to convert thepotential value to magnitude of the original signal. Please note that external gain cannot be lowerthan zero.13.3 Electrochemical Stripping/Deposition

Experiments→Misc. Techniques→Electrochemical Stripping/DepositionA constant polarization potential is imposed onto the working electrode, and monitor the

polarization current as a function of time. The polarization total time can be specified by the user,and it can also be specified when the polarization current reaches a certain value, lettingautomatic termination of the test.


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13.3.2 Deposition ParametersPolarization potential (V)—it is the potential applied to the measured system. For CS series

electrochemical workstation, if the polarization potential is “vs. OCP”, the negative valueindicates cathodic polarization, while positive value indicates anodic polarization. By clicking onthe drop-down box, users can choose the applying way of polarization potential.

Polarization total time— you can specify the length of potentiostatic polarization time; timeunit can be “second”, “minute” or “hour”.13.3.3 Experiment Termination

If you select “Based on the current” and set the quiet time and current sampling interval, thesoftware will automatically terminate potentiostatic polarization test once the polarization currentis higher than the specified maximum value (anodic current) or lower than the specifiedminimum value (cathodic current).

If you choose “Based on Di/Dt”, the program will automatically terminate potentiostaticpolarization test once the Di/Dt is greater than the set value.

If you choose “Disabled”, the above two conditions to terminate test are both inoperative.13.3.4 Data Acquisition





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13.4 Bulk Electrolysis with Coulometry (BE)

Experiments→Misc.Techniques→Bulk Electrolysis with CoulometryIn Bulk Electrolysis with Coulometry (BE), a constant potential is applied and the integrated

charge is recorded as a function of time.

13.4.1File NameSee 4.1.1 File Name.

13.4.2 Parameters settingPreelec E(V): the potential value in the process of pre-electrolysisPreelec T: duration of the process of pre-electrolysisElectrolysis E(V): the potential value in the process of electrolysisElectrolysis T: duration of the process of electrolysis.End current Ratio (%): Upper limit of potential stepElectrolysis T and End current Ratio jointly determine the end of electrolysis.







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13.5 Electrochemical Potentiokinetic Reactivation(EPR)

Experiments→Misc.Techniques→Electrochemical Potentiokinetic ReactivationThis technique can be applied to evaluate susceptibility to intergranular corrosion which

can be determined by the ratio of Ir (scan activation peak current) / Ia (reactivation scan peakcurrent). It can also be obtained by the ratio Qa/Qr. When the experiment is finished, the EPRvalue can be obtained by finding the value of Ir, Ia, Qr, and Qa following the steps of “dataanalysis”→“Voltammetric analysis”→ “EPR index calculation”.


13.5.2 Parameters settingInitial E/Final E/Scan Rate: please refer to the parameter setting in technique

Potentiodynamic.Sleeping Time: the time staying at final potential.Cycles: a complete cycle is finished when scanning from the initial E to final E. The number

of cycles can be set.13.5.3 Pstat/Gstat(ECS)




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14. Graph Display

14.1 “.cor” data graph

Except for EIS data , for all the other experiments(such as potentiostatic/galvanostaticpolarization, CV, LSV, DPV, NPV...), the data file is suffixed with “.cor”.

In potentiostat mode(including all the techniques based on constant potential, constantcurrent, galvanic current), the dialog box displays real-time data in the form of graphs, and hasbuttons such as “stop”, “pause”, “reverse”.

In the working mode of data logger, it will show the exyternal signal channel and the currentrecorded data and graph.

You can directly drag a data file to the software for dataanalysis, or click here to import the “.cor” file.

Double-click the data file


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dynamic graph display window

The file name will be shown in the title bar of the window. The techniques (such aspotentiostatic, potentiodynamic), parameters(such as the scan rate, measurement time, workingstatus, total data amount, etc) , and test progress will be shown in the status bar at the bottom ofthe window.

CS Studio will automatically find the best beginning and ending point in the coordinates andrefresh the graph in real time.CS studio will automatically choose the best beginning and ending point of the coordinate,

and refresh the graph.

14.1.1 Coordinate

E vs. time- the abscissa is time in “second”; the Y- axis is the potential of the electrode.I vs. time- the abscissa is time in “second”; the Y- axis is current.E vs. I- the abscissa is current; the Y- axis is the potential of the electrode.I vs. E- the abscissa is electrode’s potential; the Y- axis is current.


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E vs. Log I- the abscissa is the logarithm of the absolute current; the Y- axis is electrode’spotential.

E+I vs. time- The abscissa is time, and the Y- axis is electrode’s potential and polarization(galvanic) current.

Q vs. Time - the abscissa is time and the Y- axis is the integral quantity of electricity.This option works only under potentiostat mode. If data logger and potentiostat work

simultaneously, then display varies according to the users’ selected menu.

14.1.2 Real-time DataIt shows the current acquired data, from left to right they are: time(s), potential(V),

current(A). If you want to know the value of a certain point on the graph, you should click the

icon on the toolbar and move the mouse cursor to this specific point on the graph. The valuewill be displayed immediately at the right side of the cursor. For example, if you choose “E-T”,then the text will be the time and potential; And if you select “E-I”, then the text will be currentdensity and potential.

14.1.3 Zoom InIf you need to observe graphic or data of a local position during the test, you can left-press

the mouse button on the upper-left side of the target area, and drag it to the lower- right side, andthen release the button. The selected graph will be immediately zoomed in and fill up the entirewindow. The graph will not be updated, but CS Studio testing system is still scanning andacquiring data signals. If you want to go back to the original state of auto updating, please justclick the mouse on the graph.Stop and Pause

Click to terminate the ongoing test. Click to pause the test, re-click to resume thetesting.Reverse Scan Direction

Click button then the scan direction will be reversed. It is only applied inpotentiodynamic and CV test. A single click will make the scan direction reverse, and the scanrate keeps unchanged. Click again, then the direction will be reversed again, back to the originaldirection. You can use this button to reverse the scan direction any time in order to study thecyclic characteristics of some electrochemical reactions.

Polarization switch

Click button then you can change the state of the electrode polarization any time.Print

Click button, then the real-time graph in the window will be output to the printerimmediately.

Graph Copy

Click button then the real-time graph in the window can be copied into a common officedocument.

Auto zoom

Click button then the real-time graph will zoom in and fill up the entire graph window.

app:ds:quantity


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Coordinate Grid

Click button, the coordinate grids will be shown, click it again to cancel the grid.Show Parameters

Click button then the testing parameters can be shown, click it again to cancel display.Show Mark

Click button to display the mark. Click it again to cancel display.Help

Click to get help info. of the testing at present.

14.2 “.z60” data

CS Studio will display the real-time impedance data. The user can read the testing points bythe cursor on the graphs. At the same time, the real part, the imaginary part, the impedancemodular, phase angle and frequency will be displayed. The measuring data will be savedautomatically.

Real-time data

Click , the user can read the coordinates(including real part, imaginary part, frequency,impedance modular and phase angel) of the data points in “Nyquist” or “Bode” plot, as shown inbelow. If you want to know the value of a certain data point on the graph, you can move thecursor to the graph area, then the data will be displayed immediately on the right of the cursor.

EIS vs. Frequency display window

The file name will be displayed in the title bar. Parameters such as the AC amplitude, thescan range, current range etc will be shown in the lower part of the window. The software willautomatically choose the best starting and end points of the coordinate, and adjust the coordinatedisplay mode.

Zoom inIf you need to observe graphic or data of a local position during the test, you can left-press

the mouse button on the upper-left side of the target area, and drag it to the lower- right side, andthen release the button. The selected graph will be immediately zoomed in and fill up the entire


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window. The graph will not be updated, but CS Studio testing system is still scanning andacquiring data signals. If you want to go back to the original state of auto updating, please justclick the mouse on the graph.

Note: Due to the large amount of data handling during the test, you’d better use the zoom infunction after the measurement.

Stop

Click button to stop the testing and change from polarization status to natural status.WaveformThe waveform window shows the acquired potential and current waveform during EIS test,

and guide the users to choose the suitable “Min. High Freq.” and “Bandwidth” in the analyzerdialog box. If the noise is big, you probably should increase capacitance value of the bandwidthfilter, and prevent oscillation of the measurement system.

During the EIS test of the high-impedance system, if you don’t open the bandwidth responsecapacitor, in analyzer dialog box, then oscillation may happen, as shown in below. In this picture,there is no sine waveform , and amplitude doesn’t equal to 10mV, meaning the measuring systemdoesn’t follow the applied sine waveform and oscillation occurs.

(close bandwidth capacitor) acquired potential / current waveform(oscillation appears)

Choose the bandwidth capacitance to be “22pF”, then you can get the normal sine wavesignals, meaning the instrument can response to the applied sine wave signals, and worksproperly. As shown in below picture, the amplitude of the potential signals is 10mV, inaccordance with the amplitude of the applied signals. Meanwhile, the current signal is around100μA, matching to the selected current range 200μA.

If the current amplitude is too big or too small, big error will exist in the measuredimpedance spectroscopy. The user should readjust the min. High freq. in analyzer setting.

If it is just the fact that the noise of current signal is big, then the cause may be the highinput impedance of the reference electrode loop (eg. high-impedance coating). You shouldincrease the capacitance of the bandwidth filter to improve the stability of the testing system.


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(selecting 22pF capacitor) Acquired potential/current waveform(normal sine wave signals)

15. Tools

15.1 Data Export

This command is to export the data file of the active window, and save as data file suffixedwith “.cor”, unlike the “save project as” in the “file” menu. The format is “.csp” if you choose“save project as” in the “file” menu.

15.2 Data fitting

Under the menu, there are: tafel fitting, linear fit, integration, Noise, cell information,modify data, Rp fit, Least square method etc.

Fitting dialog box


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15.2.1 Modify DataThis is used to change the current data file. Before saving, you must make the date file to be

active data set in the data message box. During the switch, there will be a prompt to ask if savethe data. Yes - to save the modified data, No - to retrieve to be the original data.

This is mainly to modify the original data, and achieve data and graph offset. Aftermodification, all the data are changed.

If you want subtraction, you only need to choose the Addition method and enter a negativevalue. If you want “division”, you just need to change the corresponding relationship.

15.2.2 Cell info.See Cell Setting 3.2.Electrode area is the working area of the working electrode. If it is 1.0, the current density

will be the same as the measured current in value.CS Studio uses material’s density or the chemical equivalent to calculate the corrosion rate.

Chemical equivalent = atomic weight/the number of electrons transferred in the reaction. Forexample, for Fe-2e→Fe2+, the number of transferred electrons is 2, then the chemical equivalentis 55.8/2=27.9.

If such values are not entered, then the software only calculate the polarization resistance Rp

or the Tafel slope, not computing corrosion rate.“Polarity convention” determines how the positive/negative potential/current is interpreted.

When choose the normal “O2+”, a more positive potential will produce a bigger oxidation force,meanwhile the generated current is positive. In a typical water environment (pH=0), when thepotential is +1.23V(vs NHE), the oxygen will precipitate on the surface of the working electrode.If employing the reverse “O2-”, a more negative potential will produce a bigger oxidation force,the oxidation current value is negative. At this time, in a typical water environment (pH=0),when the potential is -1.23V(vs NHE), oxygen will be precipitated on the surface of the WE.

15.2.3 Rp fittingThe polarization resistance is the slope of the E-I curve near the open circuit potential.If the data range is set to be “auto”, CS Studio will automatically find the open circuit

potential, and choose data range of 20mV per side of the OCP. If you don’t think this is anappropriate range, you can re-position the mouse on the curve to select a data range, or enter amaximum and minimum potential directly.

Fitting results:Rp (Ohms/cm2): slope of the curveE0(V): The potential where polarization current direction changes. They usually keep in

accordance with the OCP of the system.I0(A/cm2): current density is computed based on the Stern-Geary equation (Stern-Geary, J.

Electrochem.Soc. 104,561957)

��ull ��

��

Because the Tafel slope (Ep& bc) cannot be obtained directly in linear polarization area, CS


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studio program assume it to be 0.12V/dec, thus for Stern Geary coefficient:

� ��

��

�husu/�� Normally, the B is 18mV. Of course, it can be set by the user in cell info.

��ull/mA/cm�� 8mVRP

Corrosion rate is calculated according:MPY =Icorr (A/cm2)×chemical equivalent (g/mol)×393.7(mil/cm)÷density(g/cm3)×365×

24×3600(s/Y)÷96500(C/mol);mm/a = MPY÷39.37(mil/mm).For carbon steel,1mm/a = 11.73×Icorr(mA/cm2)，1MPY = 462.2×Icorr（mA/cm2)

Therefore, only after the electrode parameters are set can the corrosion rate of metal becalculated.

15.2.4 Tafel fittingIt provides four methods. The method “Fit Anodic between cursors” and “Fit cathodic

between cursors” are the same. “Fit auto Tafel” and “Fit auto Tafel between cursors” are thesame.

The anodic/cathodic fitting are based on linear fitting principle:

� � �s �s�i �s�� i �s

− �i �s��

If fitting Ba, then i = i0 × [10(E-Eo)/Ba] can be simplified as: lgi = E/Ba + lg i0 – E0/Ba.Then it becomes a linear equation. i0 and Ba can be calculated.

Using the same method, you can calculate Bc. If fitting the Ba and Bc, then we can calculateE0 and i0 more accurately.

Auto fittingBy auto fitting, the software will automatically find the data range 200mV on both side of

the open circuit potential, and then do the anodic and cathodic fitting respectively, obtaining twoequations. Then the more accurate i0 and E0will be obtained, then calculate the corrosion rate.

15.2.5 Least square methodThis method is usually used to do fitting of multi parameters, such as 4-, or 5- parameters

fitting. It uses Levenberg-Marquardt fitting. If iL is not used, then the equation is:

� � �s �s�i �s�� i �s

− �i �s��

If using the iL, then the fitting equation is as follows:

� � ��ull ��i �s�� i

�i�i �s��

� i�s

�� i �i

�i �s��

During fitting, you must assign the initiative value.


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After obtaining the Ba, Bc, Stern-Geary is computed according to the following:

� ��

��

�husu/�� If the data range is set Auto, CS studio software will automatically find the OCP(potential at

which the current approaches zero), then choosing 250mV range for anodic and cathodic part. Ifyou don’t think it’s a suitable range, you can re-choose a range by re-locating the cursor in thecurve. Then only data points between the two cursors are involved in the computing. You canalso enter maximum and minimum to directly determine the computing range.

15.2.6 Linear fitThere are six types of fitting, but each of the latter five methods is based on the first type, i.e.,

according to linear equation: y = a + bx.PrincipleThe linear fitting employed the least square method.

θ a,b ��

�

/�� i � i ��

Through computing the acquired data point, we can obtain the value of a,b to makeminimum θ(a,b).

�t/�,��

�i ��

�

�� i � i �� s�

�t/�,��

�i ��

�

�� i � i �� s�

Expand the equation:

��

�

��

�

��

��

�

��

�

��

��

�

��

Other linear fittingThe other linear fitting are conversion of the first type. Take the function i=i0×10E/B as an

example:Firstly you should judge the sign of the i, either all positive or all negative for i. Convert the

equation to be lg i = lg i0 + E/B. Assume:lg i = y, lg i0 = a, 1/B = b, then it’s simplified to be astandard linear equation. Find the value of lg i0 and 1/B, then calculate the i0 and B indirectly. Thevalue of i0 is determined by the sign of i.

15.2.7 IntegrationThere are two kinds of integration, with and without background, but the calculationmethod is the same, using trapezoidal integration.Q(Quantity of electric charges)


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Trapezoidal integration means to calculate the area of the trapezoid constituted by twoadjacent points, that is, to do trapezoidal integration for every data point on the I-T graph. In thisway, the current value is the bottoms, and the time difference (Δt) is the height (see the picture asbelow). The sum of each trapezoidal area is the quantity of electric charges.

Electricity is trapezoidal integral, that is, for each adjacent two points constitute a trapezoidarea calculation. That is, the current-time graph of each data points trapezoidal integration, sothat the current value for the bottom and bottom, and the time difference (Δt) is high (Figure 2.92below). For each trapezoidal area to accumulate and sum, is to find the size of the power.

Q integration area diagram

Q (background)If the Q is with background, then we should find the area between two points and the

connection line of them. As shown in below picture, the area of the gird is to be obtained. Itequals to the difference between the area of the point collection and the area of the lines betweentwo points.

Q integration(background) area diagram


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15.2.8 NoiseEmploy the method of root-mean-square (RMS) to calculate the noise between cursors, and

show the results.E_RMS represents the RMS value of the potential noise after removing the background

drift.I_RMS represents the RMS value of the current noise after removing the background drift.The formula is as follows:

RMS � i��n xi

��n

Where n is the data number involved in the calculation, xi is the #i data value.Note: the results of the calculation strongly depend on quality of the data, sampling rate,

influence of filter and ambient noise etc. The validity of results depends entirely on the user’sjudgment.

15.3 Voltammetry Analysis

In the menu of voltammetry analysis, there are: CV, DPV, NPV and EPR index calculation.

15.3.1 Cyclic VoltammetryCV graph DisplayIn the data file, there is cycle mark, so the graph can display each cycle. If the number of

cycles≥2, then there is radio button “Show”. Check it, you can adjust the graph display, i.e.,from which cycle to which cycle, as you decide.

AutoBecause multi-cycles exist, the program provides a method to find the peak: divide the data

points cycle by cycle, then find the peak and valley of each cycle, and find a baseline whichparallels the X axis most, computing the peak value and half-peak area. You can find the peakand baseline manually.


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CV auto analysis

Anodic peak between cursors

Through swapping cursor , you can locate the beginning and ending point. The programwill make the scan direction as baseline, and find the highest point as the peak. The peak andhalf-peak area can be calculated.

Anodic peak interface between cursors

Cathodic peak between cursors

Through swapping cursor , you can locate the beginning and ending point. Then thesoftware will find the peak height and the half-peak area according to the baseline and thebottom point.

Cathodic peak interface between cursors

In CV analysis, in order to show the altitude, the coordinate axis must be I vs. E.Capacitance calculationFor CV graph, you can calculate the capacitance according to the following formula:


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C � �� t��ᦙ�

Where E1 is the minimum potential value in CV scan; E2 is the maximum potential value inCV scan

ΔE=E2-E1, v is the scan rateThe result interface is shown as below:

Segment 2:Area = 1.6438E-05 WΔE = E2-E1 = 0.79803 V

Scan rate=0.05 V/sC = 0.00020598F

15.3.2 Differential Pulse Voltammetry (DPV)It provides two methods: auto and peak between cursors.Two methods are supplied for DPV: auto and peak value between the cursors.AutoThe software will automatically find the maximum current value as the peak height, and

find the place where the slope is near to zero to be the baseline, then calculate the peak heightand half-peak area.

DPV curve in K3Fe(CN)6 system

Peak between cursorsBecause there will be error or what you obtain is not what you want for auto method, we

supply manual method. Through swapping the cursors to determine the beginning and endingpoints, the software will find the peak height and half-peak area based on the baseline andhighest point.

In voltammetric analysis, in order to show the height line, the coordinates must be I-E.


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15.3.3 Normal Pulse Voltammetry(NPV)It supplies two methods: auto and peak between the cursors.AutoFirstly you should find the median current, and then make the line that best parallels to

x-axis as the baseline, then calculate the height.

NPV curve in K3Fe (CN)6 system

ManualFind the median current of the data points of a segment, and make the baseline of the pointwhere the cursor is on, then calculate the height between two baselines.

15.4 M-S curve analysis

“Tools ” → M-S curve analysis

The generated EIS data file (.z60) is compatible to ZView software, but ZView cannot doMott-Schottky analysis. After data acquisition, you should click “Tools”→M-S curve analysis to

open the M-S curve analysis interface. Click to import a data file, click to open M-S curvefitting interface.

M-S curve analysis interface


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15.5 Filter

Two different digital filtering methods are available to eliminate burrs or noise in the datafile. You should find the suitable method according to the type of noise.

The first type is “Remove burrs”. It is especially suitable to data file that includes abnormalburrs. For every data point in the file, you can firstly choose 5 points(this point, the 2 pointsbefore it, and 2 points after it), delete the maximum and minimum one, then make the averagevalue of the left three point as the new value. Using the same method for every data point, youcan effectively remove the burrs due to range change of the potentiostat and the interferencenoise caused by the process of repeated on-off of the temperature controller or the discrete noisesignal.

The second type is “5 to 25 point smoothing”. This method employs Savitzky Golay(SG)smoothing algorithm (“Smoothing and Differentiation of Data by Simplified Least SquaresProcedures”, Analytical Chemistry, Vol. 36, No. 8, July 1964, page 1627).

If you need to use both of the two methods, you must first use the “remove burrs”.These smoothing methods do not change the saved data file. But if you switch to another

data file (via the active data selection box) after using filter, you will be prompted to save themodified data as a new file. The modified data can also be saved via Tools→Save Data File.

If you need to return to the original data, you can select the same file from the active dataselection box. When the software prompts you to save the modified data file, click “No”.Note: Please use the filter with cautiousness. The better way is to delete the noise instead ofcovering it. Improper use of the filter may cause the missing of some important information(such as the potential and current peak formed by passivation film rupture on the surface of theelectrode). Before using the digital filter, it is suggested to check the actual noise level of it isbest to use the oscilloscope to check the constant potential of the output signal level of the actuallevel of noise, so to determine whether to use digital noise filter.

15.6 Delete Data

There are three methods to delete data: delete data point, delete data range between thecursor, and delete data outside the cursor. After the data is deleted, the source file will beunchanged. The data after modification can also be saved via “Tools” → “Data Export”.

Delete data pointConsidering that there may be an abnormal data point in the data file, you can use this

command to delete this unneeded data highlighted by the cursor. After the data point is deleted,


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the source file will be unchanged. The data after modification can also be saved via “Tools”→“Data Export”.

Delete data rangeThis command is used to delete all data points between two cursors. After the data range is

deleted, the source file will be unchanged. The data after modification can also be saved via“Tools” → “Data Export”.

Delete data outside the cursorsAs we know, in an experiment(eg. Voltammetry stripping test), it is possible that there is

only a segment of data that is valid, then using this command, all the invalid data points (outsidethe two cursors) can be selected and deleted. The valid data will be analyzed. After the datapoints are deleted, the source file will be unchanged. The data after modification can also besaved via “Tools” → “Data Export”.

15.7 EIS Analysis

ZView is a powerful EIS analysis and graphing software. It can do various electrochemicalparameters computing and finish smoothing and digital filtering for the original potential andcurrent data. It can also compensate solution resistance by software. ZView interface is clear, andthe data, graphs can be easily printed and saved, and output to Word in vector mode.

ZView impedance analysis interface

Toolbar is the shortcut keys of the menu. If you put the mouse cursor on the icon, there willbe explanation of the icon. All the icon function can be achieved by menu.

15.7.1 Open data files“File”→“Data Files” to import the EIS data file on the right, as shown in below:


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ZView data import window

Activate dataChoose the data file to be analyzed in the dialog drop-down box (marked 1).

ZView: choose the active data file

Delete data rangeSelect the unwanted data range ( the part cannot be fitted by ZView) by the mouse cursor,

and then delete them through Tools →Delete Data Range.


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ZView : delete data range

15.7.2 Instant fitInstant fit is to obtain the initial value, a preparation for the latter formal fitting.

(1) Choose the element one by one for instant fitting(2) (2) Click for instant fitting.(3) Choose the suitable equivalent element(eg. the one marked 2), and obtain the initial

value of the equivalent circuit.

15.7.3 Complex circuit fittingBuild the suitable equivalent circuit based on the instant fit(see the below picture as an

example). It depends on your actual testing system.


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Choose the suitable equivalent circuit from ZView for formal fitting

Drag the data in place “1” to place “2”, as shown below:

Drag the data from the instant fit window to the initial value

Change “fixed” to “free”, and change the mode of the equivalent circuit fitting window from“Simulation” to “Fitting”.


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data fitting based on equivalent

parameters setting dialog box

The place marked with “1” are the fitting results. If you want to re-graph against the fittingresults, choose “fit result” in place “2”, and click to show the data. Copy them to theclipboard, after that, they can be copied to Excel or Origin software.


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Fitting results and fitting curve


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16. WindowsThis option is used to manage all current project subforms.CascadeAll project subforms are displayed in the form of CascadeTileAll project subforms are displayed in the form of TileArrangeAll project subforms are rearranged.Close allClose all project subforms.

17. HelpIndex and search: manualLanguage: English and Chinese optionalContact us: click to go to our company website, showing the contact info.Check for update: click to update the software to the latest versionAbout: there are some info about your instrument, such as the version of the software,

hardware, the serial no. of the instruments.18. FAQs

18.1 How to install the CS Studio software?

(1)Using USB cable to connect the computer with the workstation(USB PORT).(2)Turn ON to power on the electrochemical workstation, and use the CD or flash disk to

install software. Open the CD or flash disk, click the “USB Drives”, clickCP210xVCPInstaller_x64.exe(64 bit) or CP210xVCPInstaller_x86.exe(32 bit) .


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(3). After finishing the driver installation, in the device manager “port (COM and LPT)” willappear the project CP210X USB to UART Bridge Controller (COMX), X=1~6, COM X is thevirtual COM port number of CP210X, as shown below, the X is 3.

(4) Double-click the “Corrtest Install”, and then double-click the “CS Studio 5.***” , to installthe CS Studio software step by step following the instruction.


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(5)The software will be installed in the specified directory, and create a shortcut icon on thedesktop, as shown below:

(6). If there is communication failure during the test, please re-start the workstation and re-runthe software.18.2 Workstation Commissioning

The instrument should be put in dry, clean and corrosive-gas-free environment. During use,the power supply of both the potentiostat and PC must be connected to the ground well.

Dummy cellIf there is malfunction or something abnormal, please use the dummy cell to check following

the steps as below:1) Power on the electrochemical workstation2) connect the green clamp to the WE, the yellow clamp to the RE, and the red clamp to the CE.Based on the principles of the potentiostat, when altering the imposed potential, the RE potentialshould eternally be the imposed value. The output current should obey the Ohm law I= Voltage(imposed on RE) / R(R= resistance between WE and RE)3) Start the CS Studio, and do the potentiodynamic test: impose 0~1V scanning, then the V-Icurve should be a slant going through the dot (0,0). The slant ratio should be R×(10.1%). If itis the case, it means that potentiostat is OK.4) If the slant ratio or the value of potential/current is completely wrong, please check whetherthe crocodile clamp is broken, or whether there is poor connection between terminals on thedummy cell (the user can use the multimeter to measure the resistance between two terminals.).If these possible causes are ruled out, then it is deemed to be broken. The user should contact us(the manufacturer) for repair;5) If the result is correct using dummy cell, obvious malfunction still appears when measuring

the real system, please check carefully of the following:①The actual test system/design ofthe experiment ②Environmental interference③Reference Electrode④GND wire


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18.3 How to understand 3-electrode system

3-electrode system: the potentiostat measures and controls the voltage difference between aWE and a RE. Current flow between the WE and CE is measured. CS series Potentiostat workswith three electrodes immersed in a conductive electrolyte.

Working Electrode (WE): a sample of the corroding metal being tested.Reference Electrode (RE): an electrode with a constant electrochemical potential.WE and RE constitute measuring circuit. There is no current flow on RE.Counter Electrode (CE): a current-carrying electrode that completes the cell circuit.WE and CE constitute polarization circuit. Current flows from WE to CE.2-electrode system: there is no separate RE involved in the experiment in 2-electrode system.

When using the CS potentiostat/galvanostat for 2-electrode system, the CE can be used as RE toprovide reference potential. During the measurements, you simply need to connect the RE&CEclamp to a same electrode.18.4 What cause current overload?

(1) Current flow in I/E converter is higher than current range(2) When choosing “auto” range, when the measured current is higher than the auto range,the current overload can happen during the process of the electronic circuit’s switching tohigher range.(3) The Ov/L light blinking frequently shows that there is high-frequency noise interference.(4) RE in poor condition, high capacitance system or bad connection of electrodes can allcause current overload.

18.5 What cause potential overload?

(1) Max. voltage is higher that 10V between the RE and WE.(2) WE is unconnected.(3) Low resistance system (fuel cell, battery) in the galvanostat mode.(4) Compliance voltage of the potentiostat: applied max. voltage on the WE and CE (poweramplifier’s max. output voltage) is higher than 21~25V.(5) Broken RE or poor connection of RE.(6) High-resistance organic system where the IR drop should be overcome.

18.6 How to check the RE?

Take a newly refilled RE (same as the RE to be measured), and soak the microporousceramic at the bottom of the RE into the deionized water. Assume the potential of it is correct,and then put it with the RE to be measured into a cup holding saturated KCl solution, measurethe voltage difference between them by the electrochemical workstation or digital voltmeter. Ifthe difference is bigger than 10mV, the RE to be measured should be refilled or replaced.18.7 How to reduce the noise in electrochemical experiment?

1. Make sure the solution in salt bridge is conductive, and that the tip of the RE is drown inthe agar and connected well with the WE solution. To make sure the microporous ceramic is wellsocked, so as to reduce the RE impedance.

2. Open the filter of the system to improve stability.3. Give a serial capacitor (100nF) between the RE and CE if the noise resulted from the

solution resistance is unavoidable.


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4. For corrosion test, add a 1uF capacitor between WE and machine shell of the potentiostat(or the outer shell of the high frequency socket on the front panel of the instrument.)

5. For impedance test, make a parallel connection of a Pt wire and RE. Dip one end of the Ptwire into solution and connect the other end to RE output port by a 100nF capacitor.

6. All of the equipment in the experiment incl. the PC must be connected to the ground usinga separate ground wire. If there is no suitable ground wire, the user should use a thick copperwire to connect the PC with a nearby water tap.

7. Shut down all the possible environmental interference source such as high-power powersupply, computer monitor, stirrer, and fluorescence light etc.

8. Use the Faraday cage, and connect it to the ground.18.8 Troubleshooting

Phenomenon Cause Solution

No displayafter bootingup.

failure of connecting to the powersupply

Switch on power

the 1A fuse in the socket of the rearpanel is broken

Re-install or replace the fuse

no currentoutput

open circuit or bad contact of theelectrode cable

Check the electrode leads

Dry joint inside the WE or CE Check resistance between theelectrode lead and the workingface by a multimeter

communicationfailuresappears afterusing the USBinterface

1) poor repair stitching of the USBcablepower supply shortage for USB port

no connection to the ground forpower supply cable

replace the USB cable for abetter quality one.re-plug the USB cableConnect the PC casing to theground


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19. Service & Contact usWarranty: 3 years.We provide installation CD, installation guidance and English manual with the product.

Besides, we have a technical team with professional knowledge on electrochemistry, they canoffer technical service to solve questions about theoretical explanation, experiment designing,experimental data analysis & fitting, etc. During use, you can contact our technical support teamdirectly, and we will provide technical support by emails, calls, or on-line remote operation.If you have any questions, please contact us:Sales CenterEmail: [email protected]: (+86)27 67849450, (+86)27 67849890, (+86)13971066778Fax: (+86)27 67849890 ext. 39

Technical Support CenterPhone: (+86) 18086482080 (+86) 18086482081 (+86) 18086482082(+86) 27 67849890 ext.35/36/32Email: [email protected]: Room 501, Dingye Hall B, International Enterprise Center, Optics valley Ave., EastLake High-tech Development Zone, Wuhan, China, 430074

20. Appendix20.1 Comparison: techniques for each model20.2 Accessories list

- 1 -

Technique CS150 CS300 CS310 CS350 CS2350

Stablepolarization

Open Circuit Potential (OCP) Potentiostatic (I-T curve) Galvanostatic Potentiodynamic(DPP, Tafel plot)

Galvanodynamic(DGP) Potential Sweep-step

Transientpolarization

Multi-Potential Steps Multi-Current Steps Potential Stair-Step (VSTEP) Galvanic Stair-Step (ISTEP)

ChronoMethods

Chronopotentiometry (CP) Chronoamperometry (CA) Chronocoulometry (CC)

Voltammetry

Linear Sweep Voltammetry (LSV) # Cyclic Voltammetry (CV) Staircase Voltammetry (SCV) # Square wave voltammetry (SWV) # Differential Pulse Voltammetry (DPV) # Normal Pulse Voltammetry (NPV) # Differential Normal Pulse Voltammetry (DNPV) # Differential Pulse Amperometry (DPA) Double Differential Pulse Amperometry (DDPA) Triple Pulse Amperometry (TPA) Integrated Pulse Amperometric Detection (IPAD) ACvoltammetry (ACV) 2nd Harmonic A.C.Voltammetry (SHACV) Fourier Transform AC Voltammetry(FTACV)

EIS

EIS vs Frequency (IMP) EIS vs Time (IMPT) EIS vs Potential (IMPE)

Corrosiontesting

Cyclic polarization curve (CPP) Linear polarization curve (LPR) Electrochemical Potentiokinetic Reactivation (EPR) Electrochemical Noise(EN) Zero resistance Ammeter (ZRA)

BatteryBattery charge and discharge Galvanostatic charge and discharge(GCD)

BipotentiostatHydrogen diffusion test(HDT) Rotating ring-disk electrode (RRDE)

Extensions Data Logger Electrochemical stripping/deposition Bulk electrolysis with Coulometry(BE)

app:ds:AC

app:ds:voltammetry

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Accessories

Part # Product name SpecificationCS900 Saturated Calomel Electrode type-212(straight),type-232(bent)

type-217(double salt bridge)CS901 Ag/AgCl reference electrode Ø4mm/Ø6mmCS9001 Non-aqueous Ag/Ag+ reference electrode Ø4mm/Ø6mmCS902 Alkaline/Mercurous Oxide Reference Electrode suitable to alkaline solutionCS903 Mercury/Mercurous Sulfate Reference Electrode suitable to acid solution

CS910 Platinum conductivity electrode

CS911Platinum plate electrode(size can be customized )

99.95%,10x10x0.1mm, 10x10x0.2mm, 20x20x0.1mm,20x20x0.2mm, 20x20x0.3mm, 10x20x0.1mm

CS912 Platinum wire counter electrode 99.95%,Ø 0.5x37mm(wire)CS913 Platinum mesh electrode 10*10mm/ 20*20mm

CS915 Graphite rod Φ4/6mm, length 150mm

CS916 Graphite electrode Ø2~ Ø5mm

CS920 Glassy carbon working Electrode Ø2~ Ø5mm

CS921 Metal Electrode Carbon steel, stainless steel, copper,working area: 0.5cm2

CS922 Platinum working electrode 99.95%, Ø2mm, Ø3mmCS923 Gold working electrode 99.95%, Ø2mm, Ø3mmCS924 Silver working electrode Ø2mm / Ø3mm

CS925 Palladium working electrode Ø2mm/ Ø3mm

CS926 Pt micro electrode 10μm/25μm

CS927 Gold micro electrode 12.5μm/25μm

CS928 Glass cell + Teflon cap Glass cell: 10ml

CS930 Glass electrolytic Cell, 4 ports 250ml /150ml / 500ml /1000ml

CS932 Devnathan-Stachurski Cell(H- cells) 250ml/piece

CS933 Photoelectrochemical cell(material quartz) 30*30*30mm,40*40*40mm, 50*50*50mm

CS9330 Spectroelectrochemical cell

Quartz cuvette, teflon cap,Pt mesh(WE), Pt wire counter electrode(CE), Ag/AgClreference electrode(RE), Purging tube8mm*6.5mm*1mm/ 8mm*6.5mm*0.5mm

CS934 Tait cell 10ml, working area is 1cm2

CS935 Seal electrolytic cell 50ml/100ml/150ml/250ml

CS936

Flat corrosion cell kit -single

Single-deckworking area is 1cm2

include :Ag/AgCl reference electrodecounter electrode: Pt mesh*1 (20*20mm)

Flat corrosion cell kit -double

Double-jacketedworking area is 1cm2

include :Ag/AgCl reference electrode *1counter electrode: Pt mesh *1 (20*20mm)

CS940 Cell stand1 Base material: carbon steel.

CS941 Simple Cell Stand 2Base material: PTFEprovide 2*30ml electrolytic cup(free) ;

CS942 Electrode Polishing Kit

Alpha alumina powder 0.05µm, 0.3µm, 1µm 10g for each1 piece of Mastertex pad and a Microcloth polishing pad(Ø200mm); Carbimet disks (4000#,Ø200mm);2 pieces of glass plates

http://cn.bing.com/dict/clientsearch?mkt=zh-CN&setLang=zh&form=BDVEHC&ClientVer=BDDTV3.5.0.4311&q=%E5%85%89%E7%94%B5%E5%8C%96%E5%AD%A6%E6%B1%A0

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