Electrochemical
Instrumentation______________________________________________________________________________CH Instruments
1

Overview
CH Instruments was established in 1994. Our first instrument series, the Model 600 series electrochemical
analyzer/workstation, was introduced at the end of 1994. Since then, new products have been added to provide a fullline of electrochemical instrumentation:
Model 400C Series Time-Resolved Electrochemical Quartz Crystal Microbalance (EQCM): for electrodeposition, adsorption, and chemical or biological sensor studies.
Model 600F Series Potentiostat/Galvanostat: for general purpose electrochemical measurements, such as
kinetic measurements, electroanalysis, electrochemical sensor studies, fundamental research, corrosion, and battery
studies.
Model 700F Series Bipotentiostat: for rotating ring-disk electrodes (RRDE) and other cases where dual
channel measurements are essential.
Model 800D Series Electrochemical Detector: for either single or dual channel electrochemical detectionin flow cells, capillary electrophoresis and liquid chromatography, for chemical or biological sensors, and forconventional electroanalysis.
Model 920D Scanning Electrochemical Microscope (SECM): for electrode surface, corrosion, biologicalsamples, solid dissolution, liquid/liquid interfaces, and membrane studies.
Model 1000C Series Multi-potentiostat: 8-channel potentiostat for array electrode characterization andelectrochemical sensor studies. It can be used for eight independent cells or for eight working electrodes in the same
solution.
Model 1100D series Power Potentiostat/Galvanostat: for applications involving higher current andcompliance voltage.
Model 1200C series Handheld Potentiostat/Bipotentiostat: for electroanalysis, electrochemical sensor
studies, and field applications.
Model 1400 seires 4 Channel Potentiometer / 4 Channel Potentiostats: for simultaneous measurement
at a combination of sensors requiring amperometry or voltammetry and open-circuit methods, such as ion selective
electrodes, can be used for multianalyte sensing, in-vitro cellular studies, in-vivo cellular studies, and generationcollection experiments.
Model 1550A Pico Liter Solution Dispenser: for making high density and high accuracy solution arrays.
All models are controlled by an external PC under the Windows 7/10 environment. The instruments areeasy to install and use. No plug-in card or other hardware is required on the PC side.
These instruments provide a rich repertoire of electrochemical techniques. Most well-establishedelectrochemical techniques can be readily employed, including potential sweep, step, pulse, alternating current,
stripping, and various other techniques. For each instrument series, we provide various models to suit different
needs and budgets. Our instruments offer superior performance at competitive prices, and are ideal for both researchand teaching purposes.

2Model 400C Time-Resolved Electrochemical
Quartz Crystal Microbalance
The quartz crystal microbalance (QCM) is a variant of acoustic wave microsensors that are capable ofultrasensitive mass measurements. Under favorable conditions, a typical QCM can measure a mass change of 0.1-1
ng/cm2. QCM oscillates in a mechanically resonant shear mode under the influence of a high frequency AC electricfield which is applied across the thickness of the crystal. Figure 1b below shows an edge view of a QCM crystal
undergoing oscillatory shear distortion. The central portions of the top and bottom of the crystal are coated with atypically disk-shaped thin metal film (e.g., gold). The mass sensitivity of the QCM originates from the dependenceof the oscillation frequency on the total mass of the metal-coated crystal, including any adlayers of depositedmaterials, as given by the Sauerbrey equation:∆f = -2f02 ∆m / [A sqrt(µρ)]
where f0 is the resonant frequency of the fundamental mode of the crystal, A is the area of the gold disk coated onto
the crystal, ρ is the density of the crystal (= 2.684 g/cm3), and µ is the shear modulus of quartz (= 2.947 x 1011
g/cm.s2). For example, using our crystal, which has a 7.995-MHz fundamental frequency, a net change of 1 Hz
corresponds to 1.34 ng of mass adsorbed or desorbed onto the crystal surface of an area of 0.196 cm2.
QCM in conjunction with electrochemistry (EQCM) has been widely employed for the determination of
metals deposited onto the crystal, studies of ion-transport processes in polymer films, biosensor development, andinvestigations of the kinetics of adsorption/desorption of adsorbate molecules. In EQCM experiments,
measurements of various electrochemical parameters, such as potential, current, and charge at the working electrode,are conducted simultaneously with the acquisition of the corresponding frequency and resistance changes, using theexperimental setup shown in Figure 1a. For any model in the 400C series, application of a specific potential
waveform (e.g., triangular potential waveform for cyclic voltammetric experiments), current measurement, andfrequency counting are carried out with a potentiostat/frequency counter, which is in turn controlled by a computer.

Figure 1. Schematic representation of a typical EQCM instrument. (a) The quartz crystal has a fundamental
frequency of 7.995 MHz and is coated with thin gold films on both sides. The gold disk deposited on the top side of
the crystal is in contact with the electrolyte solution and used as the working electrode. The top view of the goldcoated crystal is also shown. (b) Edge view of QCM crystal showing shear deformation. The disk thickness andshear deformation have been exaggerated for clarity.
The 400C series contains a quartz crystal oscillator, a frequency counter, a fast digital function generator,
high-resolution and high-speed data acquisition circuitry, a potentiostat, and a galvanostat (Model 440C only). The
QCM is integrated with potentiostat and galvanostat, to facilitate simple and convenient EQCM studies. Instead of
measuring the frequency directly, the 400C series uses a time-resolved mode as follows. The observed frequency of
the QCM is subtracted from a standard reference frequency, and the resulting difference is measured by a reciprocal3technique, greatly reducing the required sampling time and yielding much better time resolution for the QCM signal.
With direct counting, a QCM resolution of 1 Hz requires 1 second of sampling time, 0.1 Hz resolution requires 10
seconds, etc. In contrast, our time-resolved mode allows the QCM signal to be measured in milliseconds with muchbetter resolution.
The potential control range of the instrument is ±10 V and the current range is ±250 mA. In addition to
QCM and EQCM measurements, the instrument is capable of a wide range of techniques, and is suitable for generalpurpose electrochemical applications. The instrument is very sensitive and very fast, capable of measuring current
down to the picoampere level. The scan rate in cyclic voltammetry can be up to 5000 V/s with a 0.1 mV potential
increment or 10000 V/s with a 1 mV potential increment.
Figure 2 shows the voltammogram of underpotential and bulk depositions of Pb from a 0.1 M HClO4
solution containing 1 mM Pb2+, and the corresponding frequency changes have been plotted as a function of theapplied potential. In Figure 2a, the cathodic peaks at –0.28 V and at ca. –0.59 V have been assigned to theunderpotential deposition of monolayer Pb and the bulk deposition of multlayers of Pb, respectively, whereas theanodic peaks at –0.41 V and at –0.28 V are attributable to the stripping of the deposited Pb. The frequency-potential
diagram (Figure 2b) displays the frequency decrease due to the deposition of monolayer Pb (about 25 Hz or 33.5 ng
between –0.28 V and –0.59 V) and the more drastic frequency decrease arising from bulk Pb deposition (a netchange of 425 Hz or 573.8 ng at ca. –0.5 V).

Figure 2. Voltammogram and QCM data of Pb underpotential deposition. Scan rate = 0.05 V/s.

Figure 3 depicts the voltammogram of the oxidation of pyrrole to form polypyrrole film at the gold-coatedcrystal and the corresponding frequency change. Five scan segments between the lower limit of –1.0 V and theupper limit of 1.0 V were conducted in this experiment. As clearly shown in Figure 3a, pyrrole monomer can beoxidized to its radical at ca. 0.65 V. When this occurred, a thin polypyrrole film was formed, resulting in a decreaseof the fundamental frequency of the quartz crystal (Figure 3b). During the first potential cycle, the net frequency
4

change was found to be 1150 Hz. In each cycle, the oscillation frequency reached a steady value once the potential
became insufficiently positive for the oxidative deposition of polypyrrole film. The subsequent potential cycles
displayed in Figure 3 demonstrate the continued growth of polypyrrole film, with the deposited mass causing the
crystal oscillation frequency to decrease further. A fast scan rate (0.1 V/s) was employed.

Figure 3. Voltammogram and QCM data of oxidation of pyrrole to form polypyrrole film. Scan rate 0.1 V/s.
The instrument can also be used to perform standard QCM measurements. Figure 4 shows QCM data for aflow cell detection experiment. The total frequency change observed was less than 8 Hz, with extremely low longterm drift and noise levels..
The model 400C series is the upgrade to the model 400/400A/400B series. The new design provides morestable and accurate potential control (1 mV, 0.02%), and it also allows the resistance change and frequency change
to be measured simultaneously.

5

Figure 4. A typical flow injection-QCM experiment. As soon as the sample is injected, the QCM starts recording
the frequency change (t = 0). The pump is stopped at 460 s (where a small glitch on the curve can be seen). The
reaction is completed about 40 min after sample injection. The total monitoring time is over 1 hr. A net change of 8
Hz is monitored. After 40 min or so, the frequency becomes very stable again (for at least more than 20 min, thefrequency drift is much less than 1 Hz).
The 400C series uses a USB port for data communication with the PC.
16-bit highly stable bias circuitry is added for current or potential bias. This allows wider dynamic range in
AC measurements. It can also be used to re-zero the DC current output.
The EQCM cell consists of three round Teflon pieces (Figure 1a). The total height is 37 mm with adiameter of 35 mm. The top piece is the cell top, which holds the reference and counter electrodes. There are also
two 2 mm holes for manual purging. The center piece is the solution cell, and the bottom piece is for mounting
purposes. Four screws are used to tighten an O-ring seal between the bottom and center pieces, with the quartz
crystal sandwiched between them. The diameter of the quartz crystal is 13.7 mm. The gold electrode diameter is 5.1mm.

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Specifications
Potentiostat
Galvanostat (Model 440C)
2, 3, or 4-electrode configuration
Potential range: -10 to 10V
Applied potential accuracy: ±1 mV, ±0.02% of scale
Potentiostat rise time: < 2 µs
Compliance voltage: ±12 V
Maximum current: ±250 mA continuous, ±350 mA peak
Reference electrode input impedance: 1×1012 ohm
Sensitivity scale: 1×10-12 - 0.1 A/V in 12 ranges
Input bias current: < 50 pA
Current resolution: 0.0015% of current range, minimum 0.3 fA
Minimum potential increment in CV: 100 µV
Fast waveform update: 10 MHz @ 16-bit
Data acquisition: 16 bit @ 1 MHz
External signal recording channel
QCM Frequency resolution: < 0.1 Hz
QCM maximum sampling rate: 1 kHz
Automatic and manual iR compensation

CV and LSV scan rate: 0.000001 to 5000 V/s
Potential increment during scan: 0.1 mV @ 1000 V/s
CA and CC pulse width: 0.0001 to 1000 sec
CA and CC minimum sample interval: 1 µs
CA and CC Steps: 320
DPV and NPV pulse width: 0.001 to 10 sec
SWV frequency: 1 to 100 kHz
i-t sample interval: minimum 1 µs
ACV frequency: 0.1 to 10 kHz
SHACV frequency: 0.1 to 5 kHz
Low-pass signal filters, automatic and manual setting
Potential and current analog output
RDE rotation control output: 0 - 10 V (430C and up)
CV simulation and fitting program
Cell control: purge, stir, knock
Data length: 128K – 16384K selectable
Dimension: 14.25”(W) × 9.25”(D) × 4.75”(H)Oscillator Box (external): 4.75"(L) × 2.6" (W) × 1.55" (H)Weight: 12 Lb.

Differences of 400C Series Models
Functions
Cyclic Voltammetry (CV)Linear Sweep Voltammetry (LSV) &Staircase Voltammetry (SCV) #,&Tafel Plot (TAFEL)
Chronoamperometry (CA)Chronocoulometry (CC)
Differential Pulse Voltammetry (DPV) #,&Normal Pulse Voltammetry (NPV) #,&Differential Normal Pulse Voltammetry (DNPV)#,&
Square Wave Voltammetry (SWV) &AC Voltammetry (ACV) #,&,$
2nd Harmonic AC Voltammetry (SHACV) #,&,$
Amperometric I-t Curve (I-t)
Differential Pulse Amperometry (DPA)
Double Differential Pulse Amperometry (DDPA)
Triple Pulse Amperometry (TPA)
Bulk Electrolysis with Coulometry (BE)
Hydrodynamic Modulation Voltammetry (HMV)
Sweep-Step Functions (SSF)
Multi-Potential Steps (STEP)
Chronopotentiometry (CP)
Chronopotentiometry with Current Ramp (CPCR)
Potentiometric Stripping Analysis (PSA)
Open Circuit Potential - Time (OCPT)
Quartz Crystal Microbalance (QCM)

400C

Galvanostat
RDE control (0-10V output)
Full version of CV simulator
Limited version of CV simulatoriR Compensation#: Corresponding polarographic mode can be performed.
&: Corresponding stripping mode can be performed.
$: Phase selective data are available.

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410C

420C

430C

440C

Model 600F Series
Electrochemical Analyzer / Workstation
The Model 600F series is designed for general purpose electrochemical measurements. The figure below
shows the block diagram of the instrument. The system contains a fast digital function generator, a direct digitalsynthesizer for high frequency AC waveforms, high speed dual-channel data acquisition circuitry, a potentiostat, anda galvanostat (available only in select models). The potential control range is ±10 V and the current range is ±250
mA. The instrument is capable of measuring current down to picoamperes. With the CHI200B Picoamp Booster andFaraday Cage (fully automatic and compatible with the CHI600F series), currents at sub-picoamperes can bemeasured. The instrument is very fast. The function generator can update at a 10 MHz rate. Two high speed andhigh resolution data acquisition channels allow both current and potential (or an external voltage signal) to besampled simultaneously at a rate of 2.5 MHz, with 16-bit resolution. The instrument provides a very wide dynamic
range of experimental time scales. For instance, the scan rate in cyclic voltammetry can be up to 1000 V/s with a 0.1
mV potential increment or 5000 V/s with a 1 mV potential increment. The potentiostat / galvanostat uses a 4electrode configuration, allowing it to be used for liquid/liquid interface measurements, and eliminating the effect of
the contact resistance of connectors and relays for high current measurements. The data acquisition systems also
allow an external input signal (such as spectroscopic) to be recorded simultaneously during an electrochemicalmeasurement.

The 600F series is the latest upgrade to our very popular 600/A/B/C/D/E series.
The changes will be faster data acquisition, 16-bit resolution, two channel simultaneously AD conversion
will be 2.5M Hz. It was 1M Hz two channel simultaneous ADC.
It allows CV at 2500V/s scan rate with 1 mV sample interval. It was at 1000V/s scan rate for 1mV sample
interval.
CA sample interval is changed from 1 usec to 0.4 usec, two channel simultaneously.
The new model has faster data transfer with USB 3 port. The real time data transfer for CV is changed from
3V/s to 12V/s. For time based techniques (such as CA and i-t), the sample interval for real time data transfer ischanged from 0.0003333 sec to 0.0001 sec.
AC impedance has a frequency up to 3M Hz.
We added current interrupt iR compensation.
We added galvanostatic intermittent titration technique (GITT) and potentiostatic intermittent titration
technique (PITT).
The 600F series also includes a true integrator for chronocoulometry.
Two 16-bit highly stable bias circuits are used for current and potential bias, allowing a wider dynamic
range in AC measurements. These can also be used to re-zero the DC current output.
The model 600F series can be upgraded to the corresponding model 700F series bipotentiostat with an addon board that includes circuitry for the second channel’s potential control, current measurement (including8

sensitivity switching), two low-pass filters, three gain stages, and channel selection. It is therefore identical to the600F series when used for single channel measurements. When it is used as a bipotentiostat, the second channel canbe controlled at an independent constant potential, to scan or step at the same potential as the first channel, or to scanwith a constant potential difference with the first channel. The second channel is available for many voltammetricand amperometric techniques.
The instrument is capable of a wide variety of electrochemical techniques, and is available with integrated
simulation and fitting software functions for both impedance and cyclic voltammetry. These features provide
powerful tools for both electrochemical mechanistic studies and trace analysis, as well as electrochemical sensor
studies.
We provide several different models in the 600F series. The following table compares the different models.
Other than what is listed, the specifications and features of these models are identical.

Specifications
Potentiostat:• Zero resistance ammeter• 2- or 3- or 4-electrode configuration• Floating (isolated from earth) or earth ground• Maximum potential: ±10 V• Maximum current: ±250 mA continuous, ±300 mA peak
• Compliance Voltage: ±13 V• Potentiostat rise time: < 1 µs, 0.8 µs typical• Potentiostat bandwidth (-3 dB): 1 MHz• Applied potential ranges: ±10 mV, ±50 mV, ±100 mV, ±650 mV,±3.276 V, ±6.553 V, ±10 V• Applied potential resolution: 0.0015% of potential range• Applied potential accuracy: ±1 mV, ±0.01% of scale• Applied potential noise: < 10 µV rms• Measured current range: ±10 pA to ±0.25 A in 12 ranges• Measured current resolution: 0.0015% of current range, minimum
0.3 fA• Current measurement accuracy: 0.2% if current range >=1e-6 A/V,
1% otherwise• Input bias current: < 10 pA
Galvanostat:• Galvanostat applied current range: 3 nA – 250 mA• Applied current accuracy: 20 pA ±0.2% if > 3e-7A, ±1% otherwise• Applied current resolution: 0.03% of applied current range• Measured potential range: ±0.025 V, ±0.1 V, ±0.25 V, ±1 V,±2.5 V, ±10 V• Measured potential resolution: 0.0015% of measured range
Electrometer:• Reference electrode input impedance: 1e12 ohm• Reference electrode input bandwidth: 10 MHz• Reference electrode input bias current: <= 10 pA @ 25°C
Waveform Generation and Data Acquisition:• Fast waveform update: 10 MHz @ 16-bit• Fast data acquisition: dual channel 16-bit ADC, 2,500,000
samples/sec simultaneously• External signal recording channel at maximum 2.5 MHz sampling
rate

Experimental Parameters:• CV and LSV scan rate: 0.000001 to 10,000 V/s• Potential increment during scan: 0.1 mV @ 1,000 V/s• CA and CC pulse width: 0.0001 to 1000 sec• CA minimum sample interval: 0.4 µs• True integrator for CC• DPV and NPV pulse width: 0.001 to 10 sec• SWV frequency: 1 to 100 kHz• i-t sample interval: minimum 0.4 µs• ACV frequency: 0.1 to 10 kHz• SHACV frequency: 0.1 to 5 kHz• FTACV frequency: 0.1 to 50 Hz, simultaneously acquire 1st, 2nd,
3rd, 4th, 5th, and 6th harmonics ACV data
• IMP frequency: 0.00001 to 3 MHz• IMP amplitude: 0.00001 V to 0.7 V rms
Other Features:• Automatic and manual positive feedback iR compensation• Current interrupt iR compensation• Current measurement bias: full range with 16-bit resolution•
Potential measurement bias: ±10V with 16-bit resolution• External potential input• Potential and current analog output• Programmable potential filter cutoff: 1.5 MHz, 150 KHz, 15 KHz,
1.5 KHz, 150 Hz, 15 Hz, 1.5 Hz, 0.15 Hz• Programmable signal filter cutoff: 1.5 MHz, 150 KHz, 15 KHz, 1.5
KHz, 150 Hz, 15 Hz, 1.5 Hz, 0.15 Hz• RDE control output (Model 630E and up): 0-10V (corresponding
to 0-10000 rpm), 16-bit, 0.003% accuracy• Digital input/output lines programmable through macro command• Flash memory for quick software update• USB port for data communication• Cell control: purge, stir, knock• CV simulation and fitting program, user-defined mechanisms• Impedance simulation and fitting program• Maximum data length: 256K-16384K selectable• Dimensions: 14.25”(W) × 9.25”(D) × 4.75”(H)• Weight: 12 lb.

Amperometric i-t Curve.

Square wave voltammogram.
9

Differences of 600F Series Models
Functions
Cyclic Voltammetry (CV)Linear Sweep Voltammetry (LSV) &Staircase Voltammetry (SCV) #,&Tafel Plot (TAFEL)
Chronoamperometry (CA)Chronocoulometry (CC)
Differential Pulse Voltammetry (DPV) #,&Normal Pulse Voltammetry (NPV) #,&Differential Normal Pulse Voltammetry (DNPV)#,&
Square Wave Voltammetry (SWV) &AC Voltammetry (ACV) #,&,$nd
2 Harmonic AC Voltammetry (SHACV) #,&,$
Fourier Transform AC Voltammetry (FTACV)
Amperometric i-t Curve (i-t)
Differential Pulse Amperometry (DPA)
Double Differential Pulse Amperometry (DDPA)
Triple Pulse Amperometry (TPA)
Integrated Pulse Amperometric Detection (IPAD)
Bulk Electrolysis with Coulometry (BE)
Hydrodynamic Modulation Voltammetry (HMV)
Sweep-Step Functions (SSF)
Multi-Potential Steps (STEP)

600F

602F

604F

610F

620F

630F

650F

660F

Potentiostatic Intermittent Titration Tech (PITT)AC Impedance (IMP)
Impedance - Time (IMPT)
Impedance - Potential (IMPE)
Chronopotentiometry (CP)
Chronopotentiometry with Current Ramp (CPCR)
Multi-Current Steps (ISTEP)

Galvanostatic Intermittent Titration Tech (GITT)
Potentiometric Stripping Analysis (PSA)
Electrochemical Noise Measurement (ECN)Open Circuit Potential - Time (OCPT)
Galvanostat
RDE control (0-10V output)
Full version of CV simulation and fitting program
Limited version of CV simulation and fitting program
Impedance simulation and fitting programiR Compensation
External Potential Input
Auxiliary Signal Measurement Channel#: Corresponding polarographic mode can be performed.
&: Corresponding stripping mode can be performed.
$: Phase selective data are available.

Cyclic voltammogram at 1000V/s.

Phase selective second harmonic AC voltammogram.
10Model 700F Series Bipotentiostat
The Model 700F series are computerized general purpose potentiostat / bipotentiostat / galvanostat
instruments. A typical application involves a rotating ring-disk electrode (RRDE), but these systems can also be
used for other applications where dual channel measurements are essential, such as dual channel electrochemical
detection. The system contains a fast digital function generator, a direct digital synthesizer for high frequency AC
waveforms, high speed dual-channel data acquisition circuitry, (bi)potentiostat, and a galvanostat (only available inselect models). The potential control range is ±10 V and the current range is ±250 mA. The instrument is capable ofmeasuring current down to tens of picoamperes. The steady state current of a 10 µm disk electrode can be readilymeasured without external adapters. With the CHI200B Picoamp Booster and Faraday Cage (fully automatic andcompatible with the 700E series), currents down to 1 pA can be measured (primary current channel only). These
instruments are very fast. The function generator can update at a 10 MHz rate. Two high speed and high resolution
data acquisition channels allow both current channels or current and potential (or an external voltage signal) to besampled simultaneously at 2.5 MHz rate with 16-bit resolution. The instrument provides a very wide dynamic rangeof experimental time scales. For instance, the scan rate in cyclic voltammetry can be up to 1000 V/s with a 0.1 mV
potential increment or 5000 V/s with a 1 mV potential increment. The potentiostat / galvanostat uses a 4-electrodeconfiguration, allowing it to be used for liquid/liquid interface measurements and eliminating the effect of thecontact resistance of connectors and relays for high current measurements. The data acquisition systems allow an
external input signal (such as spectroscopic) to be recorded simultaneously during an electrochemical measurement.
The instrument will also automatically re-zero both potential and current, so that periodic re-calibration of the
instrument can be avoided.
The 700F series shares many common features with the 600F series. When used as a single channel
potentiostat, the instrument is identical to the model 600F series. The bipotentiostat is realized with an add-on boardthat includes circuitry for the second channel’s potential control, current measurement, two filter stages, three extra
gain stages, and channel selection circuitry. When it is used as a bipotentiostat, the second channel can be controlled
at an independent constant potential, to scan or step at the same potential as the first channel. In case of CV, it canalso scan with a constant potential difference with the first channel. Techniques available for the second channel
include CV, LSV, SCV, CA, DPV, NPV, SWV, and i-t.
The 700F series is the latest upgrade to our very popular 700/A/B/C/D/E series.
The changes will be faster data acquisition, 16-bit resolution, two channel simultaneously AD conversion
will be 2.5M Hz. It was 1M Hz two channel simultaneous ADC.
It allows CV at 2500V/s scan rate with 1 mV sample interval. It was at 1000V/s scan rate for 1mV sample
interval.
CA sample interval is changed from 1 usec to 0.4 usec, two channel simultaneously.
The new model has faster data transfer with USB 3 port. The real time data transfer for CV is changed from
3V/s to 12V/s. For time based techniques (such as CA and i-t), the sample interval for real time data transfer ischanged from 0.0003333 sec to 0.0001 sec.
AC impedance has a frequency up to 3M Hz.
We added current interrupt iR compensation.
We added galvanostatic intermittent titration technique (GITT) and potentiostatic intermittent titration
technique (PITT).
Two 16-bit highly stable bias circuits are used for current and potential bias, allowing wider dynamic range
in AC measurements. These can also be used to re-zero the DC current output.
The instrument is capable of a wide variety of electrochemical techniques, and is available with integrated
simulation and fitting software functions for both impedance and cyclic voltammetry. These features provide
powerful tools for both electrochemical mechanistic studies and trace analysis, as well as electrochemical sensor
studies.
We provide several different models in the 700F series. The following table compares the different models.
Other than what is listed, the specifications and features of these models are identical.

Chronoamperometric data.

Voltammogram at rotating ring-disk electrode.
11Specifications
Potentiostat / Biptentiostat:• Zero resistance ammeter• 2- or 3- or 4-electrode configuration• Floating (isolated from earth) or earth ground• Maximum potential: ±10 V for both channels• Maximum current: ± 250 mA continuous (sum of two current
channels), ±300 mA peak
• Compliance Voltage: ±13 V• Potentiostat rise time: < 1 µs, 0.8 µs typical• Potentiostat bandwidth (-3 dB): 1 MHz• Applied potential ranges: ±10 mV, ±50 mV, ±100 mV, ±650 mV,±3.276 V, ±6.553 V, ±10 V• Applied potential resolution: 0.0015% of potential range• Applied potential accuracy: ±1 mV, ±0.01% of scale• Applied potential noise: < 10 µV rms• Measured current range: ±10 pA to ±0.25 A in 12 ranges• Measured current resolution: 0.0015% of current range, minimum 0.3
fA• Current measurement accuracy: 0.2% if current range >= 1e-6 A/V,
1% otherwise• Input bias current: < 20 pA
Galvanostat:• Galvanostat applied current range: 3nA – 250mA• Applied current accuracy: 20 pA ± 0.2% if > 3e-7 A, ±1% otherwise• Applied current resolution: 0.03% of applied current range• Measured potential range: ±0.025 V, ±0.1 V, ±0.25 V, ±1 V, ±2.5 V,±10 V• Measured potential resolution: 0.0015% of measured range
Electrometer:• Reference electrode input impedance: 1e12 ohm• Reference electrode input bandwidth: 10 MHz• Reference electrode input bias current: <= 10 pA @ 25°C
Waveform Generation and Data Acquisition:• Fast waveform update: 10 MHz @ 16-bit• Fast data acquisition: dual channel 16-bit ADC, 1,000,000
samples/sec simultaneously• External signal recording channel at maximum 2.5 MHz sampling
rate

12

Experimental Parameters:• CV and LSV scan rate: 0.000001 to 10,000 V/s, two channels
simultaneously• Potential increment during scan: 0.1 mV @ 1,000 V/s• CA and CC pulse width: 0.0001 to 1000 sec• CA minimum sample interval: 0.4 µs, both channels• CC minimum sample interval: 1 µs
• True integrator for CC• DPV and NPV pulse width: 0.001 to 10 sec• SWV frequency: 1 to 100 kHz• i-t sample interval: minimum 1 µs, both channels• ACV frequency: 0.1 to 10 kHz• SHACV frequency: 0.1 to 5 kHz• FTACV frequency: 0.1 to 50 Hz, simultaneously acquire 1st, 2nd,
3rd, 4th, 5th, and 6th harmonics ACV data
• IMP frequency: 0.00001 to 3 MHz• IMP amplitude: 0.00001 V to 0.7 V rms
Other Features:• Automatic and manual positive feedback iR compensation• Current interrupt iR compensation• Current measurement bias: full range with 16-bit resolution•
Potential measurement bias: ±10V with 16-bit resolution• External potential input• Potential and current analog output• Programmable potential filter cutoff: 1.5 MHz, 150 KHz, 15
KHz, 1.5 KHz, 150 Hz, 15 Hz, 1.5 Hz, 0.15 Hz• Programmable signal filter cutoff: 1.5 MHz, 150 KHz, 15 KHz,
1.5 KHz, 150 Hz, 15 Hz, 1.5 Hz, 0.15 Hz• RDE control output (Model 730F and up): 0-10V (corresponding
to 0-10000 rpm), 16-bit, 0.003% accuracy• Digital input/output lines programmable through macro command• Flash memory for quick software update• USB port for data communication• Cell control: purge, stir, knock• Maximum data length: 256K-16384K selectable• CV simulation and fitting program, user defined mechanisms• Impedance simulation and fitting program• Dimension: 14.25”(W) × 9.25”(D) × 4.75”(H)• Weight: 12 lb.

Differences of 700F Series Models
Functions
Cyclic Voltammetry (CV)*Linear Sweep Voltammetry (LSV) &,*Staircase Voltammetry (SCV) #,&,*
Tafel Plot (TAFEL)
Chronoamperometry (CA)*Chronocoulometry (CC)
Differential Pulse Voltammetry (DPV) #,&,*
Normal Pulse Voltammetry (NPV) #,&,*
Differential Normal Pulse Voltammetry (DNPV)#,&
Square Wave Voltammetry (SWV) &,*AC Voltammetry (ACV) #,&,$
2nd Harmonic AC Voltammetry (SHACV) #,&,$
Fourier Transform AC Voltammetry (FTACV)
Amperometric i-t Curve (i-t)*
Differential Pulse Amperometry (DPA)
Double Differential Pulse Amperometry (DDPA)
Triple Pulse Amperometry (TPA)
Integrated Pulse Amperometric Detection (IPAD)
Bulk Electrolysis with Coulometry (BE)
Hydrodynamic Modulation Voltammetry (HMV)
Sweep-Step Functions (SSF)
Multi-Potential Steps (STEP)

700F

710F

720F

730F

Potentiostatic Intermittent Titration Tech (PITT)AC Impedance (IMP)
Impedance - Time (IMPT)
Impedance - Potential (IMPE)
Chronopotentiometry (CP)
Chronopotentiometry with Current Ramp (CPCR)
Multi-Current Steps (ISTEP)

Galvanostatic Intermittent Titration Tech (GITT)
Potentiometric Stripping Analysis (PSA)
Electrochemical Noise Measurement (ECN)Open Circuit Potential - Time (OCPT)
Galvanostat
RDE control (0-10V output)
Full version of CV simulation and fitting program
Limited version of CV simulation and fitting program
Impedance simulation and fitting programiR Compensation
External Potential Input
Auxiliary Signal Measurement Channel#: Corresponding polarographic mode can be performed.
&: Corresponding stripping mode can be performed.
$: Phase selective data are available.
*: Second channel (bipotentiostat mode) can be performed.

RDE Voltammograms at different rotation rates

Koutecky-Levich plot
13

750F

760F

Model 800D Series Electrochemical Detector
The Model 800D series is designed for electrochemical detection; it can be used for monitoring the current
passing through a flow cell in liquid chromatography/electrochemistry or in-flow injection analysis, as well as otherelectroanalytical applications. The system contains a digital function generator, a data acquisition system, and apotentiostat / bipotentiostat / galvanostat. The potential control range is ±10 V, the current range is ±10 mA, and the
maximum sampling rate is 1 MHz at 16-bit resolution. The instrument is capable of measuring current down topicoamperes. This series is designed for analytical use that requires high sensitivity and low noise levels, and its
circuitry has very low electrical noise. The instrument allows an external input signal (such as spectroscopic) to berecorded simultaneously with electrochemical measurements. When used for amperometric detection, three decadesof current scales are plotted during the experiment to display signals of various magnitudes clearly. Compared withanalog instruments, this instrument is much easier to use and also includes standard digital data storage and analysis
capabilities, without the need for recorder or baseline adjustments. It also provides a much larger current dynamic
range, so that separate runs for large and weak signals can be avoided.
The Model 8×0D performs single channel measurements, while the Model 8×2D contains a bipotentiostat
for dual-channel measurements, such as rotating ring-disk electrode applications. Dual channel measurements areavailable for CV, LSV, CA, DPV, NPV, SWV, and amperometric i-t techniques. The 2nd channel can be controlled
at an independent constant potential, to scan or step at the same potential as the first channel, or to CV scan at aconstant potential difference with the first channel.
The model 800D series is an upgrade to our model 800/800A/800B/800C series. The instrument utilizes
flash memory, allowing instrument firmware updates to be done by electronic file transfer.
The 800D series uses a USB port for data communication with the PC.
The 800D series also has a true integrator for chronocoulometry.
Several different models are available in the 800D series. The following table compares the different
models. Other than what is listed, the specifications and features of these models are identical. Models 800D/802D
and 810D/812D are mainly for flow cell detection. Models 820D/822D are intended for voltammetry applications
and cannot be used for flow cell detection. Models 830D/832D are comprehensive electrochemical analyzers thatcan be used for electrochemical detection, electrochemical sensor studies, voltammetry, and other applications.
Models 840D/842D and 850D/852D are more advanced models with a galvanostat. Models 850D/852D also include
AC voltammetry capabilities.

Real time data display for flow cell detection.

14

Specifications
Potentiostat / Biptentiostat:• Zero resistance ammeter• 2, 3, or 4-electrode configuration• Floating (isolated from earth) or earth ground• Maximum potential: ±10 V for both channels• Maximum current: ±10 mA• Compliance Voltage: ±13 V• Potentiostat rise time: < 2 µs
• Applied potential ranges: ±3.276 V, ±6.553 V, ±10 V• Applied potential resolution: 0.0015% of potential range• Applied potential accuracy: ±1 mV, ±0.01% of scale• Applied potential noise: < 10 µV rms• Measured current range: ±10 pA to ±0.001 A in 10 ranges• Current resolution: 0.0015% of current range, minimum 0.3 fA• Current measurement accuracy: 0.2% if >= 1e-6 A/V, 1% otherwise• Input bias current: < 10 pA
Galvanostat:• Galvanostat applied current range: 3 nA – 10 mA• Applied current resolution: 0.03% of applied current range
Electrometer:• Reference electrode input impedance: 1e12 ohm• Reference electrode input bias current: <= 10 pA @ 25°C
Waveform Generation and Data Acquisition:• Fast waveform update: 1 MHz @ 16-bit• Fast data acquisition: 16-bit ADC, 1,000,000 samples/sec• External signal recording channel

Experimental Parameters:• CV and LSV scan rate: 0.000001 to 5000 V/s• CA and CC pulse width: 0.0001 to 1000 sec• CA minimum sample interval: 1 µs
• CC minimum sample interval: 1 µs
• True integrator for CC• DPV and NPV pulse width: 0.001 to 10 sec• SWV frequency: 1 to 100 kHz• i-t sample interval: minimum 1 µs
• ACV frequency: 0.1 to 10 kHz• SHACV frequency: 0.1 to 5 kHz
Other Features:• Automatic and manual iR compensation• External potential input• Potential and current analog output• Programmable potential filter• Programmable signal filter• RDE control output (Model 840D and up): 0-10V (corresponding to 010000 rpm), 16-bit, 0.003% accuracy• Flash memory for quick software update• USB port for data communication• Cell control: purge, stir, knock• Maximum data length: 256K-16384K selectable• CV simulation and fitting program, user defined mechanisms• Dimension: 14.25”(W) × 9.25”(D) × 4.75”(H)• Weight: 12 lb.

Differences of 800D Series Models
Functions

810D/812D

800D/802D

Cyclic Voltammetry (CV)*Linear Sweep Voltammetry (LSV) &,*Staircase Voltammetry (SCV) #,&,*
Tafel Plot (TAFEL)
Chronoamperometry (CA)*Chronocoulometry (CC)
Differential Pulse Voltammetry (DPV) #,&,*
Normal Pulse Voltammetry (NPV) #,&,*
Differential Normal Pulse Voltammetry (DNPV)#,&
Square Wave Voltammetry (SWV) &,*AC Voltammetry (ACV) #,&,$
2nd Harmonic AC Voltammetry (SHACV) #,&,$
Amperometric i-t Curve (i-t)*
Differential Pulse Amperometry (DPA)
Double Differential Pulse Amperometry (DDPA)
Triple Pulse Amperometry (TPA)
Integrated Pulse Amperometric Detection (IPAD)
Bulk Electrolysis with Coulometry (BE)
Hydrodynamic Modulation Voltammetry (HMV)
Sweep-Step Functions (SSF)
Multi-Potential Steps (STEP)
Chronopotentiometry (CP)
Chronopotentiometry with Current Ramp (CPCR)
Multi-Current Steps (ISTEP)
Potentiometric Stripping Analysis (PSA)
Electrochemical Noise Measurement (ECN)Open Circuit Potential - Time
Galvanostat
RDE control (0-10V output)
Full version of CV simulator
Limited version of CV simulatoriR Compensation
External Potential Input
Auxiliary Signal Measurement Channel#: Corresponding polarographic mode can be performed.
&: Corresponding stripping mode can be performed.
#: Second channel (bipotentiostat) mode can be performed.

15820D/822D

830D/832D

840D/842D

850D/852D

Model 920D
Scanning Electrochemical Microscope
The scanning electrochemical microscope (SECM) was introduced in 19891 as an instrument that could
examine chemistry at high resolution near interfaces. By detecting reactions that occur at a small electrode (the tip)as it is scanned in close proximity to a surface, the SECM can be employed to obtain chemical reactivity images of
surfaces and quantitative measurements of reaction rates. Numerous studies with the SECM have now been reported
from a number of laboratories all over the world, and the instrument has been used for a wide range of applications,
including studies of corrosion, biological systems (e.g., enzymes, skin, leaves), membranes, and liquid/liquidinterfaces.2 Trapping and electrochemical detection of single molecules with the SECM has also been reported.
The CHI920D Scanning Electrochemical Microscope consists of a digital function generator, abipotentiostat, high resolution data acquisition circuitry, a three dimensional nanopositioner, and a sample and cellholder. Diagrams for the SECM and cell/sample holder are shown below. The three dimensional nanopositioner has
a spatial resolution down to nanometers but it allows a maximum traveling distance of 50 millimeters. The potential
control range of the bipotentiostat is ±10 V and the current range is ±250 mA. The instrument is capable ofmeasuring current down to sub-picoamperes.
In addition to SECM imaging, other modes of operation are available for scanning probe applications:
Probe Scan Curve, Probe Approach Curve, Surface Interrogation SECM, and Surface Patterned Conditioning. The
Probe Scan Curve mode allows the probe to move in the X, Y, or Z direction while the probe and substratepotentials are controlled and currents are measured. The probe can be stopped when the current reaches a specified
level. This is particularly useful in searching for an object on the surface and determining approach curves. The
Probe Approach Curve mode allows the probe to approach the surface of the substrate. It is also very useful indistinguishing the surface process, using PID control. The step size is automatically adjusted to allow fast surface
approach, without letting the probe touch the surface. Surface Patterned Conditioning allows user to edit a pattern
for surface conditioning by controlling the tip at two different potentials and durations. Constant height, constantcurrent, potentiometric, and impedance modes are available for SECM imaging and probe scan curve.
The 920D is designed for scanning electrochemical microscopy, but many conventional electrochemical
techniques are also integrated for convenience, such as CV, LSV, CA, CC, DPV, NPV, SWV, ACV, SHACV,FTACV, i-t, DPA, DDPA, TPA, SSF, STEP, IMP, IMPE, IMPT, and CP. When it is used as a bipotentiostat, thesecond channel can be controlled at an independent constant potential, to scan or step at the same potential as thefirst channel, or to scan with a constant potential difference with the first channel. The second channel works withCV, LSV, CA, DPV, NPV, DNPV, SWV, and i-t.
The 920D SECM is an upgrade to the 900/910B/920C SECM. The 920D uses a stepper motor positioner in
conjunction with a closed-loop 3-dimensional piezo positioner. The stepper motor positioner has a resolution of 8
nanometers with 50 mm travel distance. Closed-loop piezo control allows improved linearity and reduced hysteresisof the piezo devices. Improvements include very stable and accurate potential and current control, and dual-channel
data acquisition at high speed (1 MHz with 16-bit resolution).
1. A. J. Bard, F.-R. F. Fan, J. Kwak, and O. Lev, Anal. Chem. 61, 132 (1989); U.S. Patent No. 5,202,004 (April 13, 1993).
2. A. J. Bard, F.-R. Fan, M. V. Mirkin, in Electroanalytical Chemistry, A. J . Bard, Ed., Marcel Dekker, New York, 1994, Vol.
18, pp 243-373.

Diagram of Scanning Electrochemical Microscope

16

Bipotentiostat (Upper) and Positioner Controller (Lower)

Cell/Sample Holder

17

CHI920D SECM Specifications

Techniques

Nanopositioner:
X, Y, Z resolution: 1.6 nm with Piezo positioner, closed loop
control, 8 nm with stepper motor positioner
X, Y, Z total distance: 50 mm
Potentiostat / Biptentiostat:• Zero resistance ammeter• 2- or 3- or 4-electrode configuration• Floating (isolated from earth) or earth ground• Maximum potential: ±10 V for both channels• Maximum current: ±250 mA continuous (sum of two current
channels), ±350 mA peak
• Compliance Voltage: ±13 V• Potentiostat rise time: < 1 µs, 0.8 µs typical• Potentiostat bandwidth (-3 dB): 1 MHz• Applied potential ranges: ±10 mV, ±50 mV, ±100 mV, ±650 mV,±3.276 V, ±6.553 V, ±10 V• Applied potential resolution: 0.0015% of potential range• Applied potential accuracy: ±1 mV, ±0.01% of scale• Applied potential noise: < 10 µV rms• Measured current range: ±10 pA to ±0.25 A in 12 ranges• Measured current resolution: 0.0015% of range, minimum 0.3 fA• Measured current accuracy: 0.2% if range >= 1e-6 A/V, else 1%• Input bias current: < 20 pA
Galvanostat:• Galvanostat applied current range: 3 nA – 250 mA• Applied current accuracy: 20 pA ± 0.2% if > 3e-7 A, else ± 1%
• Applied current resolution: 0.03% of applied current range• Measured potential range (V): ±0.025 , ±0.1, ±0.25, ±1, ±2.5, ±10• Measured potential resolution: 0.0015% of measured range
Electrometer:• Reference electrode input impedance: 1e12 ohm• Reference electrode input bandwidth: 10 MHz• Reference electrode input bias current: <= 10 pA @ 25°C
Waveform Generation and Data Acquisition:• Fast waveform update: 10 MHz @ 16-bit• Fast data acquisition: dual channel 16-bit ADC, 1,000,000
samples/sec simultaneously• External signal recording channel at max 1 MHz sampling rate
2D and 3D Graphics:• Interactive visualization of SECM surfaces• Color mapping• Laplacian smoothing• Stereoscopic 3D anaglyph imaging• High compatibility (Windows 7, 10)
Other Features:• Software tilt adjustment on XY Plane for probe scan and imaging• Automatic and manual iR compensation• Current measurement bias: full range with 16-bit resolution,
0.003% accuracy• Potential measurement bias: ±10 V with 16-bit resolution, 0.003%
accuracy• External potential input• Potential and current analog output• Programmable potential and filter cutoffs: 1.5 MHz, 150 KHz, 15
KHz, 1.5 KHz, 150 Hz, 15 Hz, 1.5 Hz, 0.15 Hz• RDE control output: 0-10V (corresponding to 0-10000 rpm), 16bit, 0.003% accuracy• Digital input/output lines programmable through macro command• USB port for data communication• Cell control: purge, stir, knock• Maximum data length: 256K-16384K selectable• Real Time Absolute and Relative Distance Display• Real Time Probe and Substrate Current Display• Dual-channel mode: CV, LSV, CA, DPV, NPV, SWV, i-t• CV simulation and fitting program, user defined mechanisms• Impedance simulation and fitting program

Scanning Probe Techniques:• SECM Imaging (SECM): constant height, constant current,
potentiometric and impedance modes• Probe Approach Curves (PAC)• Probe Scan Curve (PSC): constant height, constant current,
potentiometric, impedance, and constant impedancemodes• Surface Patterned Conditioning (SPC)• Surface Interrogation SECM (SISECM)• Z Probe Constant Current Control
Sweep Techniques:• Cyclic Voltammetry (CV)• Linear Sweep Voltammetry (LSV)• Tafel Plot (TAFEL)
Step and Pulse Techniques:• Staircase Voltammetry (SCV)• Chronoamperometry (CA)• Chronocoulometry (CC)• Differential Pulse Voltammetry (DPV)• Normal Pulse Voltammetry (NPV)• Differential Normal Pulse Voltammetry (DNPV)• Square Wave Voltammetry (SWV)AC Techniques:• AC Voltammetry (ACV)• Second Harmonic AC Voltammetry (SHACV)• Fourier Transform AC Voltammetry (FTACV)• AC Impedance (IMP)• Impedance versus Potential (IMPE)• Impedance versus Time (IMPT)
Galvanostatic Techniques:• Chronopotentiometry (CP)• Chronopotentiometry with Current Ramp (CPCR)• Multi-Current Steps (ISTEP)• Potentiometric Stripping Analysis (PSA)
Other Techniques:• Amperometric i-t Curve (i-t)• Differential Pulse Amperometry (DPA)• Double Differential Pulse Amperometry (DDPA)• Triple Pulse Amperometry (TPA)• Integrated Pulse Amperometric Detection (IPAD)• Bulk Electrolysis with Coulometry (BE)• Hydrodynamic Modulation Voltammetry (HMV)• Sweep-Step Functions (SSF)• Multi-Potential Steps (STEP)• Electrochemical Noise Measurement (ECN)• Open Circuit Potential - Time (OCPT)• Various Stripping Voltammetry• Potentiometry
Experimental Parameters:• CV/LSV scan rate: 0.000001 to 10,000 V/s, two channels
simultaneously• Potential increment during scan: 0.1 mV @ 1,000 V/s• CA and CC pulse width: 0.0001 to 1000 sec• CA minimum sample interval: 1 µs, both channels• CC minimum sample interval: 1 µs
• True integrator for CC• DPV and NPV pulse width: 0.001 to 10 sec• SWV frequency: 1 to 100 kHz• i-t sample interval: minimum 1 µs, both channel• ACV frequency: 0.1 to 10 kHz• SHACV frequency: 0.1 to 5 kHz• FTACV frequency: 0.1 to 50 Hz, simultaneous acquire 1st, 2nd,
3rd, 4th, 5th, and 6th harmonics ACV data
• IMP frequency: 0.00001 to 1 MHz• IMP amplitude: 0.00001 V to 0.7 V RMS

18

Principles and Applications of SECM
When the tip is rastered in the x-y plane above thesubstrate, the tip current variation represents changes in
topography or conductivity (or reactivity). One canseparate topographic effects from conductivity effects
by noting that over an insulator iT is always less thaniT,∞, while over a conductor iT is always greater thaniT,∞.
In the feedback mode of the SECM operation as
stated above, the overall redox process is essentiallyconfined to the thin layer between the tip and thesubstrate. In the substrate-generation/tip-collection(SG/TC) mode (when the substrate is a generator andthe tip is a collector), the tip travels within a thindiffusion layer generated by the substrate electrode.1b,3There are some shortcomings which limit theapplicability of the SG/TC mode if the substrate islarge: (1). the process at a large substrate is always
non-steady state; (2). a large substrate current may
cause significant iR-drop; and (3). the collection
efficiency, i.e., the ratio of the tip current to thesubstrate current, is low. The tip-generation/substratecollection (TG/SC) mode is advisable for kinetic
measurements, while SG/TC can be used formonitoring enzymatic reactions, corrosion, and otherheterogeneous processes at the substrate surface.

I. Operational Principles of SECM
As in other types of scanning probe microscopes,
SECM is based on the movement of a very small
electrode (the tip) near the surface of a conductive or
insulating substrate.1 In amperometric SECM experiments, the tip is usually a conventional ultramicroelectrode (UME) fabricated as a conductive diskof metal or carbon in an insulating sheath of glass or
polymer. Potentiometric SECM experiments with ionselective tips are also possible.2
In amperometric experiments, the tip current isperturbed by the presence of the substrate. When the tip
is far (i.e. greater than several tip diameters) from thesubstrate, as shown in Fig. 1A, the steady-state current,
iT,∞, is given by
iT,∞ = 4nFDCa
where F is Faraday’s constant, n is the number ofelectrons transferred in the tip reaction (O + ne → R),
D is the diffusion coefficient of species O, C is theconcentration, and a is the tip radius. When the tip ismoved toward the surface of an insulating substrate, thetip current, iT, decreases because the insulating sheathof the tip blocks diffusion of O to the tip from the bulk
solution. The closer the tip gets to the substrate, thesmaller iT becomes (Fig 1B). On the other hand, with aconductive substrate, species R can be oxidized back to
O. This produces an additional flux of O to the tip andhence an increase in iT (Fig. 1C). In this case, thesmaller the value of d, the larger iT will be, with iT → ∞as d → 0, assuming the oxidation of R on the substrate
is diffusion-limited. These simple principles form thebasis for the feedback mode of SECM operation.

II. Applications
A. Imaging and positioning
A three-dimensional SECM image is obtained byscanning the tip in the x-y plane and monitoring the tip

Figure 1. Operating principles of SECM. (A). With
UME far from the substrate, diffusion of O leads to asteady-state current, iT,∞; (B). With the UME placednear an insulating substrate, hindered diffusion of O
leads to iT < iT,∞; (C). with UME near a conductive
substrate, positive feedback of O leads to iT > iT,∞.

Figure 2. SECM image of a polycarbonate filtration
membrane with a 2-µm-diameter Pt disk UME in
Fe(CN)64- solution. Average pore diameter is ca. 10µm.
19

current, iT, as a function of tip location. A particularadvantage of SECM in imaging applications, comparedto other types of scanning probe microscopy, is that the
response observed can be interpreted based on fairly
rigorous theory, and hence the measured current can be
employed to estimate the tip-substrate distance.
Moreover, SECM can be used to image the surfaces ofdifferent types of substrates, both conductors andinsulators, immersed in solutions. The resolution
attainable with SECM depends upon the tip radius. For
example, Fig. 2 shows one SECM image of a filtration
membrane obtained with a 2-µm-diameter Pt disk tip in
Fe(CN)64- solution. Average pore diameter is ca. 10µm. An image demonstrating the local activity of an
enzymatic reaction on a filtration membrane is shownin Fig. 9 as described below.
B. Studies of heterogeneous electron transfer
reactions
SECM has been employed in heterogeneous kinetic
studies on various metal, carbon and semiconductor
substrates.4 In this application, the x-y scanning featureof SECM is usually not used. In this mode, SECM has
many features of UME and thin layer electrochemistrywith a number of advantages. For example, thecharacteristic flux to an UME spaced a distance, d,from a conductive substrate is of the order of DC/d,independent of the tip radius, a, when d < a. Thus, very
high fluxes and thus high currents can be obtained. For
example, the measurement of the very fast kinetics

Of the oxidation of ferrocene at a Pt UME has been
carried out.4e Five steady-state voltammograms
obtained at different distances are shown in Fig. 3,
along with the theoretical curves calculated with thevalues of the kinetic parameters extracted from thequartile potentials. The heterogeneous rate constant, ko,obtained (3.7 ± 0.6 cm/sec) remains constant within therange of experimental error, while the mass-transfer
rate increases with a decrease in d.
C. Studies of homogeneous chemical reactions
As mentioned above, the TG/SC (with small tip andsubstrate) mode of SECM, in the same manner as therotating ring disk electrode (RRDE), is particularly
suitable for the studies of homogeneous chemical
kinetics.1b,5 The SECM approach has the advantage thatdifferent substrates can be examined easily, i.e.,
without the need to construct rather difficult tofabricate RRDEs, and higher interelectrode fluxes areavailable without the need to rotate the electrode orotherwise cause convection in the solution. Moreover,in the TG/SC mode, the collection efficiency in theabsence of perturbing homogeneous chemical reaction
is near 100%, compared to significantly lower values inpractical RRDEs. Finally, although transient SECM
measurements are possible, most applications have
involved steady-state currents, which are easier tomeasure and are not perturbed by factors like doublelayer charging and also allow for signal averaging.
For example, the reductive coupling of both dimethylfumarate (DF) and fumaronitrile (FN) in N,N-dimethyl
formamide has been studied with the TG/SC mode.5aFig. 4 shows tip and substrate steady-state voltammograms for the TG/SC regime. Comparable values ofboth of the plateau currents indicated that the mass

Figure 3. Tip steady-state voltammograms for theoxidation of 5.8 mM ferrocene in 0.52 M TBABF4 in
MeCN at a 1.1-µm-radius Pt tip. Solid lines aretheoretical curves and solid circles are experimental
data. Tip-substrate separation decreases from 1 to 5
(d/a = ∞, 0.27, 0.17, 0.14, and 0.1). (Reprinted withpermission from Ref. 4e, copyright 1993, American
Chemical Society.)

Figure 4. SECM voltammograms for FN (28.2 mM)
reduction in TG/SC mode. d = 1.8 µm. ET wasscanned at 100 mV/sec with ES = 0.0 V vs AgQRE.
(Reprinted with permission from Ref. 5a, copyright
1992, American Chemical Society.)20

Figure 6. T/S CVs (A) curve a, d = 500 µm, andsubstrate CV (B) on Nafion/Os(bpy)33+/2+ electrode in
K3Fe(CN)6/Na2SO4, scan rate = 50 mV/sec, ET = -0.4
V vs. SCE. (Reprinted with permission from Ref. 6a,copyright 1990, American Chemical Society.)

Figure 5. Normalized tip (generation, A) and substrate(collection, B) current-distance behavior for FN
reduction. FN concentration: (open circle) 1.50 mM,(open square) 4.12 mM, (open triangle) 28.2 mM, and(filled circle) 121 mM. a = 5 µm, substrate radius is 50µm. The solid lines represent the best theoretical fit foreach set of data. (Reprinted with permission from Ref.
5a, copyright 1992, American Chemical Society.)

electrochemical behavior of an Os(bpy)32+-incorporated
Nafion film.6a T/S CV involves monitoring the tip
current vs. the substrate potential (ES) while the tip
potential (ET) is maintained at a given value and the tip
is held near the substrate. The substrate CV (iS vs. ES)of an Os(bpy)32+-incorporated Nafion film covering a
Pt disk electrode in Fe(CN)63- solution only shows awave for the Os(bpy)32+/3+ couple (Fig. 6B), indicating
the permselectivity of the Nafion coating. Fig. 6Ashows the corresponding T/S CV curves. When the tip
is far from the substrate, iT is essentially independent of
ES. When the tip is close to the substrate (d = 10 µm),
either negative or positive feedback effects areobserved, depending on the oxidation state of theOs(bpy)32+/3+ couple in the Nafion. When ES is swept
positive of the Os(bpy)32+/3+ redox wave, a positive
feedback effect is observed due to the regeneration ofFe(CN)63- in the solution gap region because of theoxidation of Fe(CN)64- by Os(bpy)33+ at the solutionfilm interface. When ES is negative of the redox wave,
the film shows negative feedback behavior, since thetransfer rate was sufficiently fast to study the rapid
homogeneous reaction. From the approach curves ofboth tip and substrate currents (Fig. 5) obtained atvarious FN concentrations, a rate constant kc = 2.0 (±0.4) x 105 M-1s-1 was determined for the dimerization
reactions.
D. Characterization of thin films and membranes
SECM is also a useful technique for studying thinfilms on interfaces. Both mediated and directelectrochemical measurements in thin films or
membranes can be carried out. For example,
polyelectrolytes, electronically conductive polymers,
passivation films on metals and dissolution processes
have been investigated by SECM.6 A unique type of
cyclic voltammetry, called tip-substrate cyclic
voltammetry (T/S CV), has been used to investigate theOs(bpy)32+ formed is unable to oxidize tip-generated
21

Fe(CN)64- back to Fe(CN)63-.
E. Liquid-liquid interfaces
One of the most promising applications of SECM is
the study of charge transport at the interface between
two immiscible electrolyte solution (ITIES).7 Unlike
conventional techniques, SECM allows for the studies
of both ion and electron transfer at the interface. For
example, uphill electron transfer, in which an electron
is transferred uphill from a redox couple with a higher
standard reduction potential in one phase to anotherredox couple having a lower standard reduction
potential in a second immiscible phase has been
demonstrated using the system TCNQ (in 1,2dichroloethane (DCE))/ferrocyanide (in water).7c Fig. 7
shows the approach curve obtained as the UME
approaches the interface when the system contains
supporting electrolytes with no partitioning ions suchas tetraphenylarsonium (TPAs+). However, the reverse
electron flow for the same redox reaction can be
induced by employing TPAs+ as a potentialdetermining ion as shown in Fig. 8. The driving force
for this reverse electron transfer is the imposition of aninterfacial potential difference by the presence insolution of TPAs+ in both phases (∆owϕ = -364 mV).
Note that the detection of reverse electron flow in thiscase could not be done using the method commonlyused for studies of
the ITIES,
e.g., cyclic
voltammetry.

Figure 8. Approach curve for the system: 10 mM
TCNQ and 1 mM TPAsTPB in DCE // 1 mM
Fe(CN)63-, 0.1 M LiCl and 1 mM TPAsCl in H2O,
showing reverse electron transfer driven by phasetransfer catalyst TPAs+. Tip potential, -0.4 V vs
Ag/AgCl. (Reprinted with permission from Ref. 7c,copyright 1995, American Chemical Society.)
Since the ITIES is not polarizable in the presence of
TPAs+ in both phases, any attempt to impose externallya potential across the interface with electrodes in twophases would result in interfacial ion transfer and acurrent flow. The SECM approach does not suffer
form this interference. Charge transfer processes
across the ITIES with or without membranes have also
been studied.
F. Probing patterned biological systems
SECM has been actively employed to probe
artificially or naturally patterned biological systems.8
Both amperometric and potentiometric techniqueswith ion-selective tips can be used. A direct test of the
SECM’s ability to image an enzymatic reaction over a
localized surface region8a is shown in Fig. 9. Glucose
oxidase (GO) hydrogel was filled inside small, welldefined pores of polycarbonate filtration membranes.
The buffered assay solution contained a highconcentration of D-glucose as well as two redox
mediators, methyl viologen dication (MV2+) andneutral hydroquinone (H2Q). Fig. 9a shows an image
obtained with a tip potential of -0.95 V vs. a silver
quasi reference electrode (AgQRE) where MV2+ was
reduced to MV+.. Since MV+. does not react with
reduced GO at the hydrogel-filled region, a negative
feedback current was obtained. However, with the tip
potential changed to 0.82 V, where hydroquinone wasoxidized to p-benzoquinone by reduced GO, an
increased tip current was observed (Fig. 9b). This
positive feedback current over the hydrogel region
indicates a significant catalytic feedback of thehydroquinone and provides a direct image of the local
enzymatic reaction.

Figure 7. Approach curve for the system: 10 mM
TCNQ and 1 mM TPAsTPB in DCE // 1 mM Fe(CN)63and 0.1 M LiCl in H2O, showing the absence ofelectron transfer across the liquid/liquid interface. A
25-µm-diameter Pt microelectrode was used to generate
Fe(CN)64- at the electrode tip from the Fe(CN)63-. Tip
potential, -0.4 V vs Ag/AgCl.
(Reprinted withpermission from Ref. 7c, copyright 1995, American
Chemical Society.)22electrode (in deposition reactions) or as thecounterelectrode (in etching processes). The feedback
mode of fabrication utilizes the same arrangement as in
SECM imaging.
The tip reaction is selected to generate a species thatreacts at the substrate to promote the desired reaction,i.e., deposition or etching. For example, a strongoxidant, like Br2, generated at the tip can etch the areaof the substrate, e.g., GaAs, directly beneath the tip.9d
The mediator reactant is chosen to be one that reacts
completely and rapidly at the substrate, thus confining
the reaction to a small area on the substrate andproducing features of area near that of the tip. Smalltip size and close tip-substrate spacing are required forhigh resolution.

III. References
1. (a). A. J. Bard, F.-R. F. Fan, J. Kwak, and O. Lev,
Anal. Chem. 1989, 61, 132; (b). A. J. Bard, F.-R. F.
Fan, and M. V. Mirkin in Electroanalytical
Chemistry, Vol.18 (A. J. Bard, ed.), Marcel Dekker,
New York, 1994, p. 243.
2. e.g., (a). For a review of early potentiometric SECM
experiments, see Ref. 1b; (b). C. Wei, A. J. Bard, G.
Nagy, and K. Toth, Anal. Chem. 1995, 67, 1346;(c). K. Toth, G. Nagy, C. Wei, and A. J. Bard,
Electroanal. 1995, 7, 801; (d). M. Kupper and J. W.
Schultze, Fres. J. Anal. Chem. 1996, 356, 187.
3. See also (a). R. C. Engstrom, M. Weber, D. J.
Wunder, R. Burgess, and S. Winquist, Anal. Chem.
1986, 58, 844; (b). R. C. Engstrom, T. Meaney, R.
Tople, and R. M. Wightman, Anal. Chem. 1987, 59,2005.
4. e.g., (a). D. O. Wipf and A. J. Bard, J. Electrochem.
Soc. 1991, 138, 469; (b). B. R. Horrocks, M. V.
Mirkin, and A. J. Bard, J. Phys. Chem. 1994, 98,
9106; (c). R. S. Hutton and D. E. Williams,
Electrochim. Acta, 1994, 39, 701; (d). N. Casillas,
P. James, and W. H. Smyrl, J. Electrochem. Soc.
1995, 142, L16; (e). M. V. Mirkin, T. C. Richards,
and A. J. Bard, J. Phys. Chem. 1993, 97, 7672; (f).
M. V. Mirkin, L.O.S. Bulhoes, and A. J. Bard, J.
Am. Chem. Soc. 1993, 115, 201; (g). J. V.
Macpherson, M. A. Beeston, and P. R. Unwin, J.
Chem. Soc. Faraday Trans. 1995, 91, 899.
5. e.g., (a). F. M. Zhou, P. R. Unwin, and A. J. Bard, J.
Phys. Chem. 1992, 96, 4917; (b). P.R. Unwin and
A. J. Bard, J. Phys. Chem. 1991, 95,7814; (c). F. M.
Zhou and A. J. Bard, J. Am Chem. Soc. 1994, 116,
393; (d). D. A. Treichel, M. V. Mirkin, and A. J.
Bard, J. Phys. Chem. 1994, 98, 5751; (e). C.
Demaille, P. R. Unwin, and A. J. Bard, J. Phys.
Chem. 1996, 100, 14137.

Figure 9. SECM images (50 µm x 50 µm) of a single
GO hydrogel-filled pore on the surface of a treatedmembrane.
Images were taken with a carbon
microelectrode tip (a = 4.0 µm). (a). Negative
feedback with MV2+ mediator at tip potential -0.95 V
vs AgQRE. (b). Positive feedback with hydroquinone
mediator at tip potential +0.82 V vs AgQRE in 0.1 M
phosphate-perchlorate buffer (pH 7.0) containing 100
mM D-glucose, 50 µM hydroquinone and 0.1 mM
MVCl2. Lightest image regions depict the greatest tip
current. (Reprinted with permission from Ref. 8a,
copyright 1993, American Chemical Society.)

G. Fabrication
The SECM can be used to fabricate microstructureson surfaces by deposition of metal or other solids or byetching of the substrate.9 Two different approaches
have been used, the direct mode9a,b and the feedback
mode9c. Typically, in the direct mode, the tip, held in
close proximity to the substrate, acts as a working

23100, 17881; (f). C. J. Slevin, J. A. Umbers, J. H.
Atherton, and P. R. Unwin, J. Chem. Soc. Faraday
Trans. 1996, 92, 5177; (g). Y. H. Shao, M. V.
Mirkin, and J. F. Rusling, J. Phys. Chem. B 1997,
101, 3202; (h). M. Tsionsky, A. J. Bard, and M. V.
Mirkin, J. Am. Chem. Soc. 1997, 119, 10785; (i).
M.-H. Delville, M. Tsionsky, and A. J. Bard,(submitted to J. Am. Chem. Soc. for publication).
8. e.g., (a). D. T. Pierce and A. J. Bard, Anal. Chem.
1993, 65, 3598; (b). B. R. Horrocks, D. Schmidtke,
A. Heller, and A. J. Bard, Anal. Chem. 1993, 65,
3605; (c). H. Yamada, H. Shiku, T. Matsue, and I.
Uchida, Bioelectrochem. Bioenerg. 1994, 33, 91;(d). B. Grundig, G. Wittstock, U. Rudel, and B.
Strehlitz, J. Electroanal. Chem. 1995, 395, 143; (e).
G. Wittstock, K. J. Yu, H. B. Halsall, T. H.
Ridgway, and W. R. Heineman, Anal. Chem. 1995,
67, 3578; (f). H. Shiku, T. Matsue, and I. Uchida,
Anal. Chem. 1996, 68, 1276; (g). J. L. Gilbert, S. M.
Smith, and E. P. Lautenschlager, J. Biomed. Mater.
Res. 1993, 27, 1357; (h). C. Kranz, T. Lotzbeyer, H.
L. Schmidt, and W. Schuhmann, Biosens.
Bioelectron. 1997, 12, 257; (i). C. Kranz, G.
Wittstock, H. Wohlschlager, and W. Schuhmann,
Electrochim. Acta, 1997, 42, 3105; (j). C. Lee, J.
Kwak, and A. J. Bard, Proc. Natl. Acad. Sci. U.S.A.
1990, 87, 1740; (k). R. B. Jackson, M. Tsionsky, Z.
G. Cardon, and A. J. Bard, Plant Physiol. 1996,
112, 354; (l). M. Tsionsky, Z. G. Cardon, A. J.
Bard, and R. B. Jackson, Plant Physiol. 1997, 113,895.
9. e.g., (a). C. W. Lin, F.-R. F. Fan, and A. J. Bard, J.
Electrochem. Soc. 1987, 134, 1038; (b). D. H.
Craston, C. W. Lin, and A. J. Bard, J. Electrochem.
Soc. 1988, 135, 785; (c). D. Mandler and A. J. Bard,
J. Electrochem. Soc. 1989, 136, 3143; (d). D.
Mandler and A. J. Bard, J. Electrochem. Soc. 1990,
137, 2468; (e). O. E. Husser, D. H. Craston, and A.
J. Bard. J. Vac. Sci. Technol. B 1988, 6, 1873; (f).
Y.-M. Wuu, F.-R. F. Fan, and A. J. Bard, J.
Electrochem. Soc. 1989, 136, 885; (g). H. Sugimura,T. Uchida, N. Shimo, N. Kitamura, and H.
Masuhara, Ultramicroscopy 1992, 42, 468; (h). I.
Shohat and D. Mandler, J. Electrochem. Soc. 1994,
141, 995; (i). S. Meltzer and D. Mandler, J. Chem.
Soc. Faraday Trans. 1995, 91, 1019; (j). C. Kranz,
H. E. Gaub, and W. Schuhmann, Advan. Mater.
1996, 8, 634; (k). J. F. Zhou and D. O. Wipf, J.
Electrochem. Soc. 1997, 144, 1202.

6. e.g., (a). C. Lee and A. J. Bard, Anal. Chem. 1990,
62, 1906; (b). C. Lee, J. Kwak, and F. C. Anson,
Anal. Chem. 1991, 63, 1501; (c). J. Kwak, C. Lee,and A. J. Bard, J. Electrochem. Soc. 1990, 137,
1481; (d). C. Lee and F. C. Anson, Anal. Chem.
1992, 64, 250. (e). I. C. Jeon and F. C. Anson, Anal.
Chem. 1992, 64, 2021; (f). M. V. Mirkin, F.-R. F.
Fan, and A. J. Bard, Science, 1992, 257, 364. (g).
M. Arca, M. V. Mirkin, and A. J. Bard, J. Phys.
Chem. 1995, 99, 5040; (h). M. Pyo and A. J. Bard,
Electrochim. Acta 1997, 42, 3077; (i). E. R. Scott,
A. I. Laplaza, H. S. White, and J. B. Phipps,
Pharmaceut. Res. 1993, 10, 1699; (j). S. R. Snyder
and H. S. White, J. Electroanal. Chem. 1995, 394,
177; (k). S. B. Basame and H. S. White, J. Phys.
Chem. 1995, 99,16430; (l). N. Casillas, S.
Charlebois, W. H. Smyrl, and H. S. White, J.
Electrochem. Soc. 1994, 141, 636; (m). D. O. Wipf,
Colloid Surf. A, 1994, 93, 251. (n). E. R. Scott, H. S.
White, and J. B. Phipps, Solid State Ionics 1992, 53,
176; (o). S. Nugnes and G. Denuault, J. Electroanal.
Chem. 1996, 408, 125; (p). M. H. T. Frank and G.
Denuault, J. Electroanal. Chem. 1993, 354, 331;(q). J. V. Macpherson and P. R. Unwin, J. Chem.
Soc. Faraday Trans. 1993, 89, 1883; (r). J. V.
Macpherson and P. R. Unwin, J. Phys. Chem. 1994,
98, 1704; (s). J. V. Macpherson and P. R. Unwin. J
Phys. Chem. 1995, 99, 14824; 1996, 100, 19475; (t).
J. V. Macpherson, C. J. Slevin, and P. R. Unwin, J.
Chem. Soc. Faraday Trans. 1996, 92, 3799; (u). K.
Borgwarth, C. Ricken, D. G. Ebling, and Heinze,
Ber. Bunsenges. Phys. Chem. 1995, 99, 1421; (v).
Y. Y. Zhu and D. E. Williams, J. Electrochem. Soc.
1997, 144, L43; (w). C. Jehoulet, Y. S. Obeng, Y. T.
Kim, F. M. Zhou, and A. J. Bard, J. Am. Chem. Soc.
1992, 114, 4237; (x). E. R. Scott, H. S. White, andJ. B. Phipps, J. Membrane Sci.. 1991, 58, 71; (y). H.
Sugimura, T. Uchida, N. Kitamura, and H.
Masuhara, J. Phys. Chem. 1994, 98, 4352; (z). J. E.
Vitt and R. C. Engstrom, Anal. Chem. 1997, 69,1070.
7. e.g., (a). C. Wei, A. J. Bard, and M. V. Mirkin, J.
Phys. Chem. 1995, 99, 16033; (b). T. Solomon and
A. J. Bard, J. Phys. Chem. 1995, 67, 2787; (c). T.
Solomon and A. J. Bard, J. Phys. Chem. 1995, 99,
17487; (d). Y. Selzer and D. Mandler, J.
Electroanal. Chem. 1996, 409, 15; (e). M. Tsionsky,
A. J. Bard, and M. V. Mirkin, J. Phys. Chem. 1996,24

Model 1000C Series Multi-Potentiostat
The model 1000C series is a computerized eight-channel potentiostat. The system contains a digital
function generator and multiplexed data acquisition circuitry. The multi-potentiostat allows eight working electrodes
in a same solution with a common reference electrode and a common counter electrode. It also allows eight
independent cells with a working electrode, a reference electrode and a counter electrode in each cell. Multiple
channels can be measured simultaneously or sequentially. However, they share a same set of experiment parameters.
Each channel can be controlled at different independent but constant potentials and different sensitivities. Or the
potentials of 2-8 channels can be scanned or stepped together with the primary channel with the same set ofparameters. You can not run channel 1 first and ask channel 2 to run while channel 1 is still running. You can notscan channel 1 at a potential range, but channel 2 at a different potential range. They all have to run the same timewith a same set of experimental time scale.
It is designed mainly for electrochemical sensor studies. The potential control range is ±10 V for all
channels and the current range is ±10 mA. The instrument is capable of measuring current down to picoamperes.
Each electrode can be individually controlled, including on/off control, potential, and sensitivity settings; each canbe set to an independent potential or the same potential as the primary channel, so that they can sweep or step
potentials together with the primary channel.
The model 1000C series is an upgrade to the model 1000/1000A/1000B series. The instrument allows eight
independent cells, simultaneous or sequential measurements, fast waveform generation and data acquisition speed(1M Hz @ 16-bit), and easy software update using flash memory.
Many electrochemical techniques are available in the 1000C series, including cyclic voltammetry andamperometric i-t measurements, with all eight channels available (except for open circuit potential measurements).
The parameters for all channels must be set before running an experiment; you cannot alter parameter settings
during experiments. During a run, you can toggle between single and multi-data set display (parallel or overlay
plots). After a run, you can choose data from any channel for parallel or overlay plotting.
The instrument can be controlled by an external PC running Windows 7/10. It is easy to install and use. The
instrument connects to your PC using USB. The commands, parameters, and options have been written using
terminology that most chemists are familiar with. A customizable toolbar allows quick access to the most commonlyused commands. A comprehensive help system provides context-sensitive information from each dialog box.
The instrument provides many powerful functions, such as straightforward file handling, extensive
experimental control, flexible graphics, various data analyses, and efficient digital simulation. Additional features
include macro commands, working electrode conditioning, color, legend and font selection, data interpolation,
visual baseline correction, data point removal, visual data point modification, signal averaging, Fourier spectrum,
and a convenient technique-specific electrochemical equation viewer. The maximum data length is 128K – 8192K
points (selectable) if real-time data transfer is allowed.

25

Differences of 1000C Series Models
Functions

1000C

1010C

1020C

1030C

1040C

Cyclic Voltammetry (CV)Linear Sweep Voltammetry (LSV) &Chronoamperometry (CA)Chronocoulometry (CC)
Differential Pulse Voltammetry (DPV) &Normal Pulse Voltammetry (NPV) &Square Wave Voltammetry (SWV) &AC Voltammetry (ACV) &2nd Harmonic AC Voltammetry (SHACV) &Fourier Transform AC Voltammetry (FTACV)
Amperometric i-t Curve (i-t)
Differential Pulse Amperometry (DPA)
Triple Pulse Amperometry (TPA)
Sweep-Step Functions (SSF)
Multi-Potential Steps (STEP)
Open Circuit Potential - Time (OCPT)
Full version of CV simulation and fitting program
Limited version of CV simulation and fitting program&: Corresponding stripping mode can be performed.

Specifications
8-Channel potentiostat(8 independent cells or a multi-working electrode cell)
Potential range (all channels): ±10 V
Applied potential accuracy: ±1 mV, ±0.01% of scale
Potentiostat rise time: < 2 µs
Applied potential noise: < 10 µV rms
Compliance voltage: ±12 V
Current range (each channel): 10 mA
Reference electrode input impedance: 1×1012 ohm
Sensitivity scale: 1×10-9 - 0.001 A/V in 7 ranges
Measured current resolution: 0.0015% of current range,
minimum 0.3 pA
Input bias current: < 50 pA
Fast waveform updating rate: 5 MHz @ 16-bit
Fast data acquisition: up to 1 MHz @ 16-bit• CV and LSV scan rate:
0.000001 to 5000 V/s (sequential scan)
0.000001 to 25 V/s (8 channel simultaneous scan)Potential increment during scan: 0.1 mV @ 500 V/s• CC and CA pulse width: 0.0001 to 1000 sec• CA and CC sample interval:
1e-6 to 50 s (sequential step)
8e-5 to 50 s (8 channel simultaneous step)• DPV and NPV pulse width: 0.001 to 10 sec• SWV frequency:
1 to 100 KHz (sequential scan)
1 to 3125 Hz (8 channel simultaneous scan)• ACV frequency:
1 to 10000 Hz (sequential scan)
1 to 312 Hz (8 channel simultaneous scan)• SHACV frequency:
1 to 5000 Hz (sequential scan)
1 to 250 Hz (8 channel simultaneous scan)• FTACV frequency: simultaneously acquire 1st, 2nd, 3rd,
4th, 5th, and 6th harmonics ACV data
0.1 to 50 Hz (sequential scan)
0.1 to 34 Hz (8 channel simultaneous scan)• i-t sample interval:
1e-6 s to 100 s (sequential step)
8e-5 s to 100 s (8 channel simultaneous step)
Current low-pass filters
Current analog output
Cell control: purge, stir, knock
Maximum data length: 128K-16384K selectable
Dimensions: 14.25”(W) × 9.25”(D) × 4.75”(H)Overlay plot of 8 channel SWV with all eight channel potential
scanned simultaneously

Overlay plot of 8 channel i-t Curve with different potential setting foreach channel

26Model 1100D Series
Power Potentiostat / Galvanostat
The Model 1100D series power potentiostat/galvanostat is designed for electrochemical applications that
require relatively large current and high compliance voltage, such as battery studies, corrosion, electrolysis, andelectroplating. The potential control range is ±10 V, the current range is ±2 A, and the compliance voltage is ±25 V.
The system contains a high speed digital function generator, a fast data acquisition system, current signal filters, iR
compensation circuitry, a potentiostat, and a galvanostat (1140D only). The function generator can update at a 10
MHz rate, and the maximum sampling rate is 1 MHz at 16-bit resolution. The 1100D series is capable of measuring
current down to tens of picoamperes. The steady state current of a 10 µm disk electrode can be readily measured
without external adapters. The instrument provides a very wide dynamic range of experimental time scales. For
instance, the scan rate in cyclic voltammetry can be up to 1000 V/s with a 0.1 mV potential increment, or 5000 V/s
with a 1 mV potential increment. The potentiostat/galvanostat uses a 4-electrode configuration, allowing it to be
used for liquid/liquid interface measurements and eliminating the effect of the contact resistance of connectors andrelays for high current measurements. The data acquisition systems allow an external input signal (such as
spectroscopic) to be recorded simultaneously with electrochemical data.
The model 1100D series is the upgrade from our model 1100C series. The major improvements are 3-4
times faster data transfer, and better protection of the power amplifier to avoid overheat and short circuit.
The 1100D series uses a USB port for data communication with the PC.
16-bit highly stable bias circuitry has been added for current or potential bias. This allows wider dynamic
range in AC measurements. It can also be used to re-zero the DC current output.
We provide several different models in the 1100D series. The following table compares the different
models. Other than what is listed, the specifications and features of these models are identical. Models
1100D/1110D are basic models, while Model 1140D is a more advanced model with a galvanostat.

Chronopotentiometric measurement27

Specifications
Potentiostat
Galvanostat (1140D only)
Potential range: -10 to 10 V
Applied potential resolution: 0.0015% of potential range
Applied potential accuracy: ±2 mV, ±0.02% of scale
Potentiostat rise time: < 2 µs
Compliance voltage: ±25 V
3- or 4-electrode configuration
Current range: ±2 A
Reference electrode input impedance: 1×1012 ohm
Sensitivity scale: 1×10-12 - 0.1 A/V in 12 ranges
Input bias current: < 50 pA
Current measurement resolution: < 1 pA
Potential update rate: 10 MHz
Data acquisition: 16-bit @ 1 MHz
External voltage signal recording channel
External potential input
Automatic and manual iR compensation
Potential and current analog output
RDE control voltage output: 0-10V (1130D and up)

CV and LSV scan rate: 0.000001 to 5000 V/s
Potential increment during scan: 0.1 mV @ 1000 V/s
CA and CC pulse width: 0.0001 to 1000 s
CA and CC Steps: 320
DPV and NPV pulse width: 0.001 to 10 s
SWV frequency: 1 to 100 kHz
CA and i-t sample interval: minimum 1 µs
ACV frequency: 0.1 to 10 kHz
SHACV frequency: 0.1 to 5 kHz
Automatic potential and current zeroing
Signal low-pass filters, covering 8-decade frequency range,
Automatic and manual setting
Potential and current analog output
Cell control: purge, stir, knock
Automatic potential and current zeroing
Current low-pass filters, covering 8-decade frequency range,
Automatic and manual setting
Flash memory for quick software update
USB port for data communication
Maximum data length: 128K-16384K selectable
Dimension: 14.25”(W) × 9.25”(D) × 4.75”(H)Weight: 17 lb.

Differences of 1100D Series Models
Functions
Cyclic Voltammetry (CV)Linear Sweep Voltammetry (LSV) &Staircase Voltammetry (SCV) #,&Tafel Plot (TAFEL)
Chronoamperometry (CA)Chronocoulometry (CC)
Differential Pulse Voltammetry (DPV) #,&Normal Pulse Voltammetry (NPV) #,&Differential Normal Pulse Voltammetry (DNPV)#,&
Square Wave Voltammetry (SWV) &AC Voltammetry (ACV) #,&,$
2nd Harmonic AC Voltammetry (SHACV) #,&,$
Amperometric i-t Curve (i-t)
Differential Pulse Amperometry (DPA)
Double Differential Pulse Amperometry (DDPA)
Triple Pulse Amperometry (TPA)
Bulk Electrolysis with Coulometry (BE)
Sweep-Step Functions (SSF)
Multi-Potential Steps (STEP)
Chronopotentiometry (CP)
Chronopotentiometry with Current Ramp (CPCR)
Multi-Current Steps (ISTEP)
Potentiometric Stripping Analysis (PSA)
Open Circuit Potential - Time (OCPT)

1100D

Galvanostat
RDE control (0-10V output)
Full version of CV simulation and fitting program
Limited version of CV simulation and fitting programiR Compensation
External Potential Input
Auxiliary Signal Measurement Channel#: Corresponding polarographic mode can be performed.
&: Corresponding stripping mode can be performed.

28

1110D

1120D

1130D

1140D

Model 1200C Series Hand-heldPotentiostat / Bipotentiostat
The Model 1200C series is a computerized hand-held potentiostat/bipotentiostat. The system contains adigital function generator, a data acquisition system, and a potentiostat/bipotentiostat, and it is well suited forelectroanalysis and sensor studies. The potential range is ±5 V and the current range is ±50 mA. This series iscapable of measuring current down to 100 pA. The steady state current of a 10 µm disk electrode can be readilymeasured. The size of the instrument is 7” (L) × 4.5” (W) × 1” (H). The instrument is powered by the USB port ofan external computer, without need of an AC adapter or batteries. Due to its small size, light weight, and low cost, it
is particularly useful for field applications and teaching laboratories.
The model 1200C series allows ±11 V compliance voltage, which ensures its working potential range of ±5
V for most electrochemical systems. It also uses dual 16-bit DAC and 16-bit ADC for high resolution and accuracy.
The instrument provides many powerful functions, such as straightforward file handling, extensive
experimental control, flexible graphics, various data analysis, and efficient digital simulation. Some of the uniquefeatures include macro commands, working electrode conditioning, color, legend and font selection, datainterpolation, visual baseline correction, data point removal, visual data point modification, signal averaging,
Fourier spectrum, and a convenient technique-specific electrochemical equation viewer.
The 1200C series provides various instrument models to meet different applications and budgets, and isavailable in potentiostat (1200C, 1210C, 1220C, 1232C, and 1240C) and bipotentiostat versions (1202C, 1212C,
1222C, 1232C and 1242C).

Specifications
Potentiostat / bipotentiostat
Maximum potential range: ±5 V
Compliance voltage: ±11 V
Current range: ±50 mA
Reference electrode input impedance: 1×1012 ohm
Sensitivity scale: 1×10-9 - 0.01 A/V in 8 ranges
Input bias current: < 100 pA
Current measurement resolution: < 1 pA
Data acquisition: 16-bit @ 100 kHz

CV and LSV scan rate: 0.000001 to 80 V/s
CA and CC pulse width: 0.001 to 1000 s
CA and CC Steps: 1 - 320
DPV and NPV pulse width: 0.001 to 10 s
SWV frequency: 1 to 5000 Hz
Low-pass filter for current measurements
Maximum data length: 128K-16384K selectable
Power: USB port
Chassis dimension: 7” (W) × 4.5” (D) × 1” (H)Differences of 1200C Series Models
Functions

1200C/1202C

Cyclic Voltammetry (CV)*Linear Sweep Voltammetry (LSV) &,*Chronoamperometry (CA)*Chronocoulometry (CC)
Differential Pulse Voltammetry (DPV) &,*Normal Pulse Voltammetry (NPV) &,*Differential Normal Pulse Voltammetry (DNPV) &,*Square Wave Voltammetry (SWV) &,*AC Voltammetry (ACV) &2nd Harmonic AC Voltammetry (SHACV) &Amperometric i-t Curve (i-t)*
Differential Pulse Amperometry (DPA)
Double Differential Pulse Amperometry (DDPA)
Triple Pulse Amperometry (TPA)
Sweep-Step Functions (SSF)
Multi-Potential Steps (STEP)
Open Circuit Potential - Time (OCPT)
Full version of CV simulation and fitting program
Limited version of CV simulation and fitting program&: Corresponding stripping mode can be performed.
*: Second channel (bipotentiostat mode) can be performed.

29

1205C
/1206C

1207C/1208C

1210C/1212C

1220C/1222C

1230C/1232C

1240C/1242CModel 1400 Series Four-Channel Potentiometer /Four-Channel Potentiostats
The model 1400 series is a computerized four-channel potentiometer and four-channel potentiostat. The
system contains a digital function generator and multiplexed data acquisition circuitry. The instrument can workwith eight independent cells or eight working electrodes in the same solution with common reference and counterelectrodes.
The potentiometer has high input impedance and low input bias current. The input range is ±10 V, allowing
dc coupled or ac coupled. A gain of 10 is also allowed. The potentiostat has a potential control range of ±10 V andthe current range is ±10 mA. The instrument is capable of measuring current down to picoamperes. Each electrodecan be individually controlled, including on/off control, potential, and sensitivity settings; each can be set to anindependent potential or the same potential as the primary channel, so that they can sweep or step potentials together
with the primary channel. The instrument allows eight independent cells, simultaneous or sequential measurements,
fast waveform generation and data acquisition speed (1M Hz @ 16-bit), and easy software update using flash
memory.
The model 1400 series can be use for array electrode characterization and sensor studies which require
simultaneous measurement at a combination of sensors requiring techniques such as amperometry or voltammetry
with sensors employing open-circuit methods, such as ion selective electrodes.
The analyzer is essential for real-time sensing at sensor arrays employing combinations of sensors for realtime detection of analytes in flux in cellular metabolism, either in 2D or 3D culture. The combination of open circuit
potential with other methods allows for the addition of ion sensors such as H+, K+, and Cl-, with sensors critical tometabolism, such as glucose, lactate, and oxygen. Additional sensing can be achieved through the Macro function in
the Analyzer program, allowing for switching between amperometric and voltammetric measurements at the same
electrodes, or conductivity measurements to determine salinity at additional electrodes in the array. This flexibility
allows for a wide range of sensors measurements schemes.
Many electrochemical techniques are available in the 1400 series. The parameters for all channels must be
set before running an experiment; you cannot alter parameter settings during experiments. During a run, you can
toggle between single and multi-data set display (parallel or overlay plots). After a run, you can choose data fromany channel for parallel or overlay plotting.
The instrument can be controlled by an external PC running Windows 7/10. It is easy to install and use. The
instrument connects to your PC using a USB port connectivity; no plug-in card or other hardware is required on thePC side. The commands, parameters, and options have been written using terminology that most chemists arefamiliar with. A customizable toolbar allows quick access to the most commonly used commands. A comprehensive
help system provides context-sensitive information from each dialog box.

30

The instrument provides many powerful functions, such as straightforward file handling, extensive
experimental control, flexible graphics, various data analyses, and efficient digital simulation. Additional features
include macro commands, working electrode conditioning, color, legend and font selection, data interpolation,
visual baseline correction, data point removal, visual data point modification, signal averaging, Fourier spectrum,
and a convenient technique-specific electrochemical equation viewer. The maximum data length is 128K – 16384K
points (selectable) if real-time data transfer is allowed.

Differences of 1400 Series Models (Potentiostatic Function Only)
Functions

1400

1410

1420

1430

1440

Cyclic Voltammetry (CV)Linear Sweep Voltammetry (LSV) &Chronoamperometry (CA)Chronocoulometry (CC)
Differential Pulse Voltammetry (DPV) &Normal Pulse Voltammetry (NPV) &Square Wave Voltammetry (SWV) &AC Voltammetry (ACV) &2nd Harmonic AC Voltammetry (SHACV) &Fourier Transform AC Voltammetry (FTACV)
Amperometric i-t Curve (i-t)
Differential Pulse Amperometry (DPA)
Triple Pulse Amperometry (TPA)
Sweep-Step Functions (SSF)
Multi-Potential Steps (STEP)
Open Circuit Potential - Time (OCPT), total 5 channels
Full version of CV simulation and fitting program
Limited version of CV simulation and fitting program&: Corresponding stripping mode can be performed.

Specifications
Four-channel Potentiometer:
Input potential range: ±10 V
Input impedance: 1×1013 ohm
Input bias current: <=1 pA
Dc and ac coupling
Gain selection: 1 or 10• DPV and NPV pulse width: 0.001 to 10 sec• SWV frequency:
1 to 100 KHz (sequential scan)
1 to 3125 Hz (8 channel simultaneous scan)• ACV frequency:
1 to 10000 Hz (sequential scan)
1 to 312 Hz (8 channel simultaneous scan)• SHACV frequency:
1 to 5000 Hz (sequential scan)
1 to 250 Hz (8 channel simultaneous scan)• FTACV frequency: simultaneously acquire 1st, 2nd, 3rd,
4th, 5th, and 6th harmonics ACV data
0.1 to 50 Hz (sequential scan)
0.1 to 34 Hz (8 channel simultaneous scan)• i-t sample interval:
1e-6 s to 100 s (sequential step)
8e-5 s to 100 s (8 channel simultaneous step)

Four-channel Potentiostat:
Potential range (all channels): ±10 V
Applied potential accuracy: ±1 mV, ±0.01% of scale
Potentiostat rise time: < 2 µs
Applied potential noise: < 10 µV rms
Compliance voltage: ±12 V
Current range (each channel): 10 mA
Reference electrode input impedance: 1×1012 ohm
Sensitivity scale: 1×10-9 - 0.001 A/V in 7 ranges
Measured current resolution: 0.0015% of current range,
minimum 0.3 pA
Input bias current: < 50 pA
Fast waveform updating rate: 5 MHz @ 16-bit
Current low-pass filters• CV and LSV scan rate:
0.000001 to 5000 V/s (sequential scan)
0.000001 to 25 V/s (8 channel simultaneous scan)Potential increment during scan: 0.1 mV @ 1,000 V/s• CC and CA pulse width: 0.0001 to 1000 sec• CA and CC sample interval:
1e-6 to 50 s (sequential step)
8e-5 to 50 s (8 channel simultaneous step)

Other features:• Fast data acquisition: up to 1 MHz @ 16-bit for single
channel, 12.5K Hz for 8 channel simultaneous• Independent cells or a multi-working electrode cell
• Simultaneous eight channel measurements or sequential
single channel measurements for higher speed and better
signal averaging• Current and potential analog output• Cell control: purge, stir, knock• Maximum data length: 128K-4096K selectable• Dimensions: 14.25”(W) × 9.25”(D) × 4.75”(H)31

CHI1550A Solution Dispenser
The CHI1550A solution dispenser is designed for making high density and high accuracy solution arrays,
which can be used in chemical, biological and medical applications. The solution dispenser consists of a highresolution three-dimensional positioner, a piezoelectric jetting device, and a sample platform, as shown in Figure 1.

Figure 1. Diagram of the solution dispenser
The three-dimensional positioner can travel 50 mm in all three directions with 0.1 micrometer resolution,
allowing high-precision patterning. This is particularly important when multiple overlapping solution components
need to be dispensed.
The jetting device can dispense single drops of solutions with viscosity less than 40 centipoise and surface
tension in the range of 0.02-0.07 N/m. Solutions with properties outside these limits can be jetted if changes to theproperties can be achieved with solvents or changes in temperature. With a default nozzle size of 60 microns, thejetting device can produce drops ranging from 100-200 picoliters in volume, depending on the operating parametersand solution composition.
The CHI1550A solution dispenser control software is very user-friendly for creating binary, ternary andquaternary arrays of spots containing mixtures of solutions. Instead of using a manually created look-up table forsolution dispensing patterns, pattern creation is facilitated by our software, which can also provide commonly usedpatterns as a default for binary, ternary, and quaternary arrays. The positioner can memorize certain critical positions,such as the solution loading point and first dispensing point, allowing the jetting device to go to these positions
easily and quickly.
The array pattern can be examined graphically, and it will also be displayed during the dispensing process.

32

Figure 3. Micropositioner and sample stand

System requirements
Operating System: PC with Microsoft Windows 7/10.
Communication: USB port

Hardware Specifications
Jetting Device:

Micropositioner:••••

Orifice size of the jetting device: 60 micron
Droplet size: 100-200 picoliters
Control voltage: 0-150 V
A protective holder for the jetting device

Maximum range of travel: 50 mm
Resolution: 0.1 um
Stall Load: 50 N
Maximum Speed: 4 mm / sec

33

CHI200B Picoamp Booster and Faraday Cage
With the CHI200(B) Picoamp Booster and Faraday Cage, current down to a few picoamperes can bereadily measured. The CHI200 is compatible with the Model 600/A, 700/A series of instruments, while the
CHI200B is compatible with Model 600B/C/D/E/F, 700B/C/D/E/F and 800B/C/D series. When used with
700/A/B/C/D/E/F and 800B/C/D series bipotentiostat, the Picoamp Booster will affect only the primary channel.
The internal sensitivity of the 600B/C/D/E/F series is the same as the Picoamp Booster (1×10-12 A/V).
However, the bias current of the 600B/C/D/E/F series input can be as high as 50 pA. The Picoamp Booster has alower bias current, and it also brings the preamplifier close to the electrode, resulting in lower noise. The Faraday
Cage also makes it possible to make relatively fast measurements of small currents.
When the Picoamp Booster is connected and the sensitivity scale is at or below 1×10-8 A/V, the Picoamp
Booster will be automatically enabled. Otherwise, it will be disabled. Detection and enabling/disabling of the
Picoamp Booster are fully automatic and do not require user intervention.
The Picoamp Booster will be disabled for techniques using automatic sensitivity switching, such as Tafelplots and bulk electrolysis (BE). For galvanostatic techniques, such as chronopotentiometry (CP),chronopotentiometry with Current Ramp (CPCR), Mulit-Current Steps (ISTEP), and potentiometric stripping
analysis (PSA), the Picoamp Booster will not work. However, it works with AC impedance (IMP).
In addition to allowing weak signal measurements, the Faraday cage is useful for eliminating electricalinterference, especially line frequency noise. If the electrochemical cell is picking up electrical noise from theenvironment, the additional use of Faraday cage is strongly recommended.

Dimension: 9.6”(W) × 8.8”(D) × 11.8”(H)Weight: 10 lb.

Cyclic voltammogram at an ultramicroelectrode.

Differential pulse voltammogram at an
ultramicroelectrode.

34Model 680D Amp Booster
With the CHI680D Amp Booster, the current can be measured up to 2 A. The compliance voltage will be
up to ±25V. The CHI680D is compatible with our model 600D/E/F series of instruments. You can stack the
CHI600D/E/F and the CHI680D together. The CHI680D can also be connected to the model 700E/F series, but it
will only work for the primary channel.
When the Amp Booster is connected, cell control signals such as purge, knock, and stir will be disabled.
The Amp Booster will also allow low current measurements. You may need to use a Faraday Cage toeliminate line frequency noise when the scan rate is above 50 mV/s.
The frequency response of the Amp Booster is somewhat lower than that of the CHI600F. For high speed
experiments, the Amp Booster should be disconnected.
Dimension: 14.25”(W) × 9.25”(D) × 4.75”(H)Weight: 17 lb.

CHI684 Multiplexer
CHI684 is a multi-channel multiplexer for the model 400/A/B/C, 600A/B/C/D/E/F, 700A/B/C/D/E/F,
800B/C/D, 900B/C/D and 1100A/B/C/D series. The multiplexer switches four lines (working, sensing, reference,and counter for single-channel potentiostats, second working, reference and counter for bipotentiostats). You canhave up to 64 cells, but only one cell can be connected at a time.
The multiplexer is controlled using the "Multiplexer" command under the Control menu. You can select any
channel(s) and run experiments in a sequence of selected channels. Data will automatically be saved to file after
each run. You can also be prompted before each channel run.
It is allowed to set arbitrary channels immediately. An experiment can then be run for that particular channel.
Two Macro commands are available for the multiplexer. One is "mch:##", which allows the user to choose anindividual channel. The other macro command is "mchn". This is used in a For...Next loop to select the channel
according to the For...Next loop counter.
The minimum number of channels for the CHI684 is 8. The channel increment is 8. The maximum number ofchannels is 64.

35

Highlights
User Interface• Unicode tabbed-document
application: compatible with
32-bit and 64-bit Windows• monolithic, streamlined
architecture: minimal registryfree footprint• multiple instances: control
multiple instruments by simply
duplicating the program• customizable toolbar: quick
access to favorite commands• status bar: technique, filestatus, and command prompt• WYSIWYG graphics• comprehensive contextsensitive help

File Management• Unicode support: international
file and folder names• open data files: read directlyfrom binary or plain-text files• save data file: binary, plaintext formats for exporting data
(e.g., to spreadsheet)• list data file• convert to text files: forexporting multiple data files• text file format• print present data
• print multiple data files• print setup

Experimental Setup• technique: a large repertoireof electrochemical techniques• experimental parameters:
extremely wide dynamic range• system setup: line frequency,
potential/ current axis polarities• hardware test: digital andanalog circuitry diagnostic test

Fourier Transform ACV 3rd Harmonics

Instrument Control• run experiment: real time data
display in most cases• pause/resume during run• stop running experiment• reverse scan direction during
run: for cyclic voltammetry• repetitive runs: automatic data
save, signal averaging, delay orprompt between runs, up to 999
runs• run status: stir, purge, iR
compensation, smooth after run,
RDE and SMDE control status• macro commands: edit, save,
read, and execute a series ofcommands• open circuit potential
measurement• iR compensation: automatic andmanual compensation, solution
resistance, double layer
capacitance and stability test
• analog filter setting: automaticor manual setting of potential,
i/V converter, and signal filters• cell control: purge, stir, cell on,
SMDE drop collection, and prerun drop knock• step functions: initial and two
step potentials, duration of steps
and number of steps, particularly
useful for electrode treatment• working electrode conditioning
before running experiment:
programmable 3 steps

Automatic ip ~ v1/2 plot.
36• rotating disk electrode: rotation
speed, on/off control during
deposition, quiescent time, run,and between runs
• stripping mode: enable/disable,
deposition potential and time, stirand purge conditions

Graphical Display• present data plot
• 3D surface plot: front, rear, side,
top and bottom view
• overlay plots: several sets ofdata overlaid for comparison• add data to overlay: adding data
files to overlay plot
• parallel plots: several sets ofdata plotted side by side
• add data to parallel: adding
data files to parallel plot
• zoom in/out: visually selectedzoom area• manual results: visually
selected baseline• peak definition: shape, width,
and report options• Special Plots: x-y, ip-v, ip-v1/2,
Ep-log v, semilog plots, linear
polarization resistance plot
• graph options: video or printeroptions, axis, parameters,baseline, results, grids, axis
inversion, axis freeze, axis titles,
data sets, XY scales, current
density option, referenceelectrode, header, and notes• 3d plotting (NEW): interactive
visualization of impedance data
and SECM results; Laplaciansmoothing, Delaunay
triangulation, and stereoscopic
3D anaglyph imaging (no special
video card or display required)

Automatic semilog plot.

Highlights• color and legend: background,axis, grid, curves, legend size,
thickness, and display intervals• font: font, style, size and color
for axis labels, axis titles, header,parameters, and results• copy to clipboard: for pasting thedata plot to word processors

Data Processing• standard addition: calculationand plot• data file report: analyticalreport from existing data files• time dependence report• corrosion rate calculation

AC Impedance
Simulation and Fitting

Digital CV Simulation andFittingView• calibration curve: calculationand plot• fast implicit finite difference
algorithm• reaction mechanisms: 10
predefined mechanisms (lowend models); or any
combination involving electrontransfer, first- and second-orderchemical reactions (high end
models)• system: diffusive or adsorptive• maximum equations: 12• maximum species: 9• simulation parameters:
standard redox potentials, rateof electron transfer, transfer
coefficient, concentration,diffusion coefficient, forward
and reverse chemical reaction
rate constants, temperature,electrode area, andexperimental parameters• simultaneous display ofvoltammogram andconcentration profiles• automatic search anddetermine over-determinedequilibrium constants• dimensionless current• equilibrium data

Concentration-time dependence plot.

Fourier spectrum.

• smoothing: 5-49 point leastsquare and Fourier transform• derivatives: 1st - 5th order, 5-49
point least square• integration• convolution: semi-derivative andsemi-integral• interpolation: 2× - 64× datainterpolation• baseline correction: visually
selected baseline, slope and dc
level compensation• baseline fitting and subtraction:
selectable fitting function,
polynomial order and potential
range for best fitting and baseline
subtraction; particularly useful for
trace analysis• data point removing• data point modifying: visual data
point modification• background subtraction:difference of two sets of data
• signal averaging• mathematical operations: both X
and Y data array• Fourier spectrum

Analysis

37• visual entry of equivalentcircuitry• automatic equivalent circuit
parameters fitting• data information: date, time,
filename, data source,
instrument model, dataprocessing performed, header
and notes• data listing: data informationand numerical data array• equations: general equations
and equations relating tovarious electrochemical
techniques• SECM probe status: probe
position and current display• clock• toolbar• status bar

Help• context sensitive help
• help topics• about the application

System requirements• operating system: Microsoft
Windows 7 / 10
• USB port for communication

Nyquist plot of impedance data.

Highlights

System setup allows any convention of current
and potential polarity.

A large repertoire of electrochemical techniques.

The Macro command allows a series command
to be executed in a sequence..

Experimental parameter dialog box for Cyclic
Voltammetry.

User interface for digital simulator.
Experimental parameter dialog box for SECM.

38

Highlights

CV Simulation displays both current response and theconcentration profiles of different species during the simulation
process.

Equations relating to various techniques
can be viewed from our software.

Impedance data plot.

Chronocoulometric data.

Multi-cycle chronopotentiometric data.

Multi-segment sweep-step functions data..

39

Accessories
Part No.
CHI101
CHI101P
CHI102
CHI102P
CHI103
CHI104
CHI104P
CHI105
CHI105P
CHI106
CHI106P
CHI107
CHI107P
CHI108
CHI108P
CHI111
CHI111P
CHI112
CHI112P
CHI115
CHI116
CHI116P
CHI117
CHI117P
CHI120
CHI125A
CHI127
CHI128
CHI129Description
2 mm dia. Gold Working Electrode2 mm dia. Gold Working Electrode2 mm dia. Platinum Working Electrode2 mm dia. Platinum Working Electrode2 mm dia. Silver Working Electrode3 mm dia. Glassy Carbon Working
Electrode
3 mm dia. Glassy Carbon Working
Electrode
12.5 µm dia. Gold Microelectrode12.5 µm dia. Gold Microelectrode25 µm dia. Gold Microelectrode25 µm dia. Gold Microelectrode
10 µm dia. Platinum Microelectrode
10 µm dia. Platinum Microelectrode25 µm dia. Platinum Microelectrode25 µm dia. Platinum Microelectrode
Ag/AgCl Reference Electrode, (porous
Teflon tip)
Ag/AgCl Reference Electrode, (porous
Teflon tip)
Non-Aqueous Ag/Ag+ ReferenceElectrode 1
Non-Aqueous Ag/Ag+ ReferenceElectrode 1
Platinum Wire Counter Electrode
10 µm dia. Platinum SECM Tip
10 µm dia. Platinum SECM Tip
25 µm dia. Platinum SECM Tip
25 µm dia. Platinum SECM Tip
Electrode Polishing Kit 2
Polished, Bounded, Mounded 100A Ti +1000 A Gold Crystal for EQCM
EQCM Cell
Reference Electrode for EQCM Cell
Pt Wire Counter Electrode for EQCM Cell

Part No.
CHI130
CHI131
CHI132
CHI133
CHI134
CHI135
CHI140A
012167

Unit
1
3/pk
1
3/pk
1
1
3/pk
1
3/pk
1
3/pk
1
3/pk
1
3/pk
1

012171
CHI150
CHI151
CHI152
CHI172Model #CHI200
CHI201
CHI202
CHI220
CHI221

3/pk
1
3/pk

CHI222
CHI223012125012126012127012033011121012026
TE100
SE101

1
1
3/pk
1
3/pk
1
1
1
1
1

Description
Thin-Layer Flow Cell
GC Working Electrode for Flow Cell
Au Working Electrode for Flow Cell
Pt Working Electrode for Flow Cell
Reference Electrode for Flow Cell
25 um Spacer for Flow Cell
Spectroelectrochemical Cell
Ag/AgCl Reference electrode for
CHI140A
Ag/Ag+Non Aqeous Ref electrode for
CHI140A
Calomel Reference ElectrodeMercury/Mercurous Sulfate ReferenceElectrode
Alkaline/Mercurous Oxide ReferenceElectrode
Electrode leads for a particular
instrument model number
Picoamp Booster and Faraday Cage 3
Picoamp Booster
Faraday Cage
Simple Cell Stand 4
Cell Top (including Pt wire counterelectrode, not a replacement part for the
CHI200 cell stand) 5
Glass Cell
Teflon Cap 5
IDA Gold Electrode
IDA Platinum Electrode
IDA Carbon ElectrodeCS-3 Remote Controllable Cell StandQCM Flow Cell Kit (no ref electrode)
EQCM Flow Cell Kit (no ref electrode)
Printed Electrodes (3-electrodes)
3mm dia. Printed carbon electrode

Unit
1
1
1
1
1
4/pk
1
1
1
1
1
1
1
1
1
1
1
1

1
1
1
1
1
1
1
40/pk
40/pk

Notes:
1. Ag+ solution (typically 10 mM) should be prepared with the supporting electrolyte and AgNO3 (not included).
This solution is then filled into the reference electrode compartment using a syringe (not included). The
instructions will come with the components.
2. The electrode polishing kit contains 1 bottle of 1.0 micron Alpha alumina powder, 1 bottle of 0.3 micron Alphaalumina powder, 3 bottles of 0.05 micron Gamma alumina powder, 2 glass plates for polishing pads, 5 pieces of
73 mm diameter 1200 grit Carbimet disks (grey in color), 5 pieces of 73 mm diameter Mastertex polishing pads
(white in color), and 10 pieces of 73 mm diameter Microcloth polishing pads (brown in color).
3. The Picoamp Booster and Faraday Cage allow current measurements down to 1 pA. Usage is fully automatic andcompatible with our model 600F and 700F series instruments (primary channel only)..
4. Made of stainless steel and Teflon (see figure below). Not remote-controllable. Four glass cells are included.
5. Not a replacement part for the CHI220 Cell Stand.

40

Accessories and Instrument Chassis

Front and rear view of the Model 400C,
600F, 700F, 800D, and 1100C series
instruments

CHI130 Thin-Layer Flow Cell

41

42

TE100 Screen Printed Electrode.

SE101: single disk working electrode (3mm diameter)

TE100: three electrodes with 3mm diameter working
electrode.

43Bridge on Colorado River,
Austin, Texas

Our office building inAustin, Texas.

Warranty:
One-year warranty on electronic parts and labor, 90-day warranty on mechanical parts.
Demo Software:Free demo software available upon request.

CH Instruments, Inc.
3700 Tennison Hill Drive • Austin, TX 78738 • USA
Tel: (512) 402-0176 • Fax: (512) 402-0186
E-mail: info@chinstruments.com
Web Page: http://www.chinstruments.com
 October 2020 CH Instruments, Inc.
All rights reserved.

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