Physical Interpretation of Mixed Ionic‐electronic Conductive Polymer‐coated Electrodes by a Simple Universal Impedance Model

Electroanalysis, vol. 35

Abstract

Abstract A simple equivalent electrical circuit is used to obtain the physical parameters of electrical circuit elements from measured electrochemical impedance spectra. This model consists of four circuit elements with a clear physical meaning for each of the elements. Compared to complex models with multiple constant phase elements or Warburg impedances, our model is suitable for extracting physical values for important electrode parameters with low errors. The feasibility of the model was shown by investigating pure metal or polymer‐coated electrodes. Here, gold electrodes were coated either with Poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT : PSS), Polypyrrole:poly(styrenesulfonate) (PPy : PSS), or (PEDOT/PPy) : PSS by means of electropolymerization. The model could demonstrate the ionic‐electronic differences such as the ion accessibility of the differently coated electrodes. To prove the correctness of the model, the obtained results were compared to the literature.

Authors 7

1. Marcel Tintelott Aachen Institute of Materials in Electrical Engineering 1

   RWTH Aachen University

   Affiliation as printed

   Institute of Materials in Electrical Engineering 1 RWTH Aachen University Sommerfeldstraße 24 D-52074 Aachen Germany

   These authors contributed equally

2. Tom Kremers Aachen Institute of Materials in Electrical Engineering 1

   RWTH Aachen University

   Affiliation as printed

   Institute of Materials in Electrical Engineering 1 RWTH Aachen University Sommerfeldstraße 24 D-52074 Aachen Germany

   These authors contributed equally

3. Anabel Mernitz Aachen Institute of Materials in Electrical Engineering 1

   RWTH Aachen University

   Affiliation as printed

   Institute of Materials in Electrical Engineering 1 RWTH Aachen University Sommerfeldstraße 24 D-52074 Aachen Germany

4. Sven Ingebrandt Aachen Institute of Materials in Electrical Engineering 1

   RWTH Aachen University

   Affiliation as printed

   Institute of Materials in Electrical Engineering 1 RWTH Aachen University Sommerfeldstraße 24 D-52074 Aachen Germany

5. Vivek Pachauri Aachen Institute of Materials in Electrical Engineering 1

   RWTH Aachen University

   Affiliation as printed

   Institute of Materials in Electrical Engineering 1 RWTH Aachen University Sommerfeldstraße 24 D-52074 Aachen Germany

6. Xuan Thang Vu Aachen Institute of Materials in Electrical Engineering 1

   RWTH Aachen University

   Affiliation as printed

   Institute of Materials in Electrical Engineering 1 RWTH Aachen University Sommerfeldstraße 24 D-52074 Aachen Germany

7. Uwe Schnakenberg corresponding Aachen Institute of Materials in Electrical Engineering 1

   RWTH Aachen University

   Affiliation as printed

   Institute of Materials in Electrical Engineering 1 RWTH Aachen University Sommerfeldstraße 24 D-52074 Aachen Germany