Equivalent Electrical Circuits and Their Use Across Electrochemical Impedance Spectroscopy Application Domains

Abstract

When studying electrochemical systems, EIS practitioners face the challenge of choosing a relevant equivalent electrical circuit to analyze their measurement data and interpreting the role of its components. In this review, we take a closer look at the use of equivalent electrical circuits (EEC) across various application domains. We aim to aid EIS practitioners in determining and evaluating their EEC-based data analysis methodology in light of recent progress from all EIS application domains. We review EEC usage and its interpretation while additionally providing software to automatically search for equivalent electrical circuits from the relevant application domain literature that fit EIS measurements supplied by users. Finally, we make a comparison of the impedimetric behaviour and circuit modelling approaches of a range of different electrochemical systems and discuss some complementary EIS data analysis strategies.

Synthesis and characterization of a nanostructure conductive copolymer based on polyaniline and polylactic acid as an effective substrate in proteins impedimetric biosensing

“…Moreover, by performing the faradaic reaction on the surface of the electrode, two other parameters including resistance to charge transfer by faradaic reactions ( R ct ) and Warburg diffusion resistance ( W ) parallel to the double layer charge ( C dl ) are observed. 36 A CV and EIS response was examined for characterization of the electrochemical profiles of PLA- b -PANI immersed in a solution containing Fe(CN) 6 3−/4− (5 mM) and KCl (0.1 M).…”

Effect of the deposition process on the stability of Ti3C2T x MXene films for bioelectronics

“…To further investigate the changes at the Ti 3 C 2 T xelectrolyte interface over the course of the study, we also fit the impedance spectra of the electrodes at t 0 and t f using previously established equivalent circuit models for Ti 3 C 2 T x MXene (detailed in Supplementary Information) [4,33]. All circuit models were built using Gamry's EChem Analyst software package and featured a charge-transfer resistance (R ct ), Warburg impedance (W), and constant phase element (CPE) to describe the Ti 3 C 2 T x electrodes, while saline was described by its spread resistance (R s ).…”

“…To characterize the changes in the electrochemical response of the electrodes, we fit the total electrochemical impedance at t 0 and at t f with previously established equivalent circuit models for Ti 3 C 2 T x electrodes [4,33]. From the fitting, we extracted the equivalent circuit parameters representing chargetransfer resistance (R ct ), double-layer capacitance (C dl ), and the Warburg impedance (W, supplementary figure S5 and table 3), and compared their values before and after aging.…”

“…We also observed a thickness dependence in the Warburg impedance magnitude, as the thin spraycoated films had higher diffusion occurring than both types of thicker films. Since the Warburg element models mass-transport and diffusion reactions [33], these changes could be indicative of moisture ingress in the films.…”

Bioimpedance Measurement under Feature Combination of Time-Frequency Domain and Application for E. coli Detection

“…5 However, most studies only analyze impedance data in the frequency domain by fitting an equivalent circuit and using charge transfer resistance Rp as the main reference index to establish a linear relationship between this index and the concentration of the target molecule. [6][7][8][9] As a result, when microbial bacteria or insulation layer cover the surface of the electrode, changes in the impedance of the interface layer and other impedance parameters cannot be ignored. Analyzing concentration solely based on a single feature Rp may result in large errors, and the applicable range of the obtained standard curves is extremely limited.…”