Time resolved impedance spectroscopy analyzer

Time resolved impedance spectroscopy analyzerSpecially designed for time-resolved impedance spectroscopy. Usually, when conducting impedance spectroscopy measurements, the impedance of the sample is subsequently measured for each frequency applied. However, if examining dynamically changing samples, their properties may undergo significant changes during frequency scanning. In this case, the generated impedance spectrum may be difficult to interpret. The time-resolved impedance spectroscopy analyzer can obtain the entire spectrum and optional scan limits at once. All frequencies are processed simultaneously. To observe the temporal evolution of the sample, many frames can be recorded at given time intervals. This instrument is capable of studying the dynamics of different types of samples, such as electrochemical sensors, materials whose properties change when exposed to a given reagent (light, temperature, catalyst, etc.), etc.

The time-resolved impedance spectroscopy analyzer measures the current flowing through the sample and the voltage on the sample, in response to the voltage signal generated by frequency superposition.

Classical impedance spectroscopy (IS) or electrochemical impedance spectroscopy (EIS) assumes that the sample is linear and time invariant (LTI).

However, as is well known, most electrochemical samples have both nonlinearity and memory.

nonlinear effect

Therefore, you can explore the following nonlinear effects in the sample:

• High harmonic generation/

• Intermodulation (when two input frequencies generate a third frequency at the output),

• Current rectification (when the resistance/impedance of the sample in one direction is different from the resistance/impedance in the other direction of the current),

• Overlay subdivision (the superposition of input frequencies will not be retained in the output).

Memory Effect Example

• Under stable environmental conditions, the time evolution of the sample impedance spectrum reveals whether previous measurements will affect the next measurement.

The results show

The measurement results are as follows:

• Three dimensional Nyquist (Argand) plot over time/

• Time Bode plot/

• Generate a time evolution graph of impedance at a given frequency contained in the signal,

• Difference chart used to observe relative changes in time/

• Collected plots of raw current and raw voltage frames.

application

Time resolved impedance spectroscopy analyzer is an ideal choice for observing real-time changes in impedance of electrochemical sensors. This type of measurement is a supplement to static photocurrent/photovoltage measurements, such as
Using photoelectrochemical (PEC) measurement station:.

Equipment module

The instrument includes:

• Measurement electronic component module

• Measuring head: Basic/Electrical,

• 12V power supply,

Time resolved impedance spectroscopy analyzer for electrochemical measurements

Time resolved impedance spectroscopy analyzerCombined with an electrochemical head and an electrochemical shielding box, it can serve as a specialized measuring device for electrochemical samples that require screening from ambient light and external electromagnetic fields.

Specifications

Time resolved impedance spectroscopy analyzer

• Number of frames in the sequence: unlimited

• Number of frequencies in the frame: unlimited

• The range of the generated potential signal is -1 ÷ 1 V,

• Measurement head type: Basic (dual electrode)/Electrochemical (three electrode),

• Sampling rate: 1.22 kHz ÷ 10 MHz,

Basic Head

• Current range: 10 mA, 1 mA

• Frequency range: 1 mHz ÷ 1 MHz,

Electrochemical head

• Current range: 1 mA, 100 μ A, 10 μ A, 1 μ A, 100 nA, 10 nA

• Bandwidth range: 2.5 MHz, 1.3 MHz, 300 kHz, 35 kHz, 3kHz, 300 Hz

measurement results

The measurement results shown below are obtained for parallel RC circuits, where the resistance depends on the intensity of oscillating illumination.

The Nyquist (or Azz) plot represents the real and imaginary parts of impedance measured at different times within a frequency range. It can be seen that the impedance value increases in the middle of the measurement sequence, and the impedance semicircle increases in diameter.

Select the same frequency measurement time point in green. If only the capacitance is changed, in an RC circuit, all semicircles have the same size, but the position of a given frequency point will move along the circle.

Single frame 3D Nyquist (Argand) plot.

Bode plots the time amplitude.

Bode draws time stages.