Impedance spectroscopy is an experimental method of characterizing electrochemical systems. This technique measures the impedance of a system over a range of frequencies, and therefore the frequency response of the system, including the energy storage and dissipation properties, is revealed. Often, data obtained by electrochemical impedance spectroscopy (EIS) is expressed graphically in a Bode plot or a Nyquist plot.

The electrochemical workstation can be used for the control and detection of electrochemical parameters such as potentials, currents, etc. The workstation uses electrodes to input and output electrical signals. The commonly used electrochemical workstation is mainly a three-electrode system, which includes a working electrode, a counter electrode, and a reference electrode. The working electrode is the place where most electrochemical reactions occur and is the most direct sensor. [Xiaoli Zhu, Liu Shi, in Nano-Inspired Biosensors for Protein Assay with Clinical Applications, 2019]