ELECTROCATALYTIC REDUCTION OF DIOXYGEN BY AN ELECTROCHEMICALLY POLYMERIZED FLAVIN ADENINE-DINUCLEOTIDE FILM

An electrochemically polymerized flavin adenine dinucleotide (FAD) film electrode is reported for the first time. The polymerized film was prepared by a two-step method. The electrocatalytic reduction of dioxygen at a glassy carbon electrode (GCE) modified with polymerized FAD (PFAD) was studied using cyclic voltammetry. Dioxygen accepts two electrons from a reduced mediator to form hydrogen peroxide. The catalytic reaction is controlled by the diffusion process. The rotating disk electrode was used to study the kinetics of the electrocatalytic reduction of dioxygen. The rate constants of the catalytic reaction in various pH solutions were obtained. The effect of the solution pH on the electrocatalytic activity of a PFAD/GCE for dioxygen reduction is discussed.