| Title |
A Study on the Electrical Circuit Model of the Electrode/Electrolyte Interface for Improving Electrochemical Impedance Fitting |
| Authors |
장종현(Chang, Jong-Hyeon) ; 박정호(Pak, Jung-Ho) |
| Keywords |
Electochemical Impedance Spectroscopy ; Electrode/Electrolyte Interface ; Electrical Circuit Model |
| Abstract |
Exact impedance modeling of the electrode/electrolyte interface is important in bio-signal sensing electrode development. Therefore, the investigation of the equivalent circuit models for the interface has been pursued for a long time by several researchers. Previous circuit models fit the experimental results in limited conditions such as frequency range, type of electrode, or electrolyte. This paper describes a new electrical circuit model and its capability of fitting the experimental results. The proposed model consists of three resistors and two constant phase elements. Electrochemical impedance spectroscopy was used to characterize the interface for Au, Pt, and stainless steel electrode in 0.9% NaCl solution. Both the proposed model and the previous model were applied to fit the measured impedance results for comparison. The proposed model fits the experimental data more accurately than other models especially at the low frequency range, and it enables us to predict the impedance at very low frequency range, including DC, using the proposed model. |