SIMULATION OF TIME-DEPENDENT PROCESSES AT REDOX POLYMER ELECTRODES

A numerical simulation of a polymer-coated electrode is presented. The model accounts for the mass transport by diffusion and migration, electron transfer through the membrane by a hopping mechanism, homogeneous chemical reaction in the membrane, heterogeneous reactions and double-layer capacitance at the interface between electrode and membrane, and the Donnan partition equilibrium at the interface between membrane and diffusion layer. The set of partial differential equations is transformed into ordinary differential equations using the method of lines with cubic Hermitian polynomials. The time integration is performed by a semi-implicit method. Calculated and measured data of cyclic voltammograms of a ruthenium polymer-coated electrode are compared and demonstrate the reliability of the model.