A NUMERICAL AC-IMPEDANCE MODEL USED FOR THE ANALYSIS OF A POLYVINYLFERROCENE COATED ELECTRODE

A numeical model to calculate the impedance plane plot of a redox polymer coated electrode bathed in an electrolyte solution is presented and used for the analysis of the experimental measurements of a polyvinylferrocene system. The model takes into account Butler-Volmer type heterogeneous redox kinetics, electron flux by hopping, diffusion and migration of the electrolyte, the Poisson's equation, Donnan partition kinetics, an IR-drop and the double layer capacitance including a constant phase element. This numerical procedure offers a powerful tool for analysing impedance data of very complex systems.