Cyclic Voltammetry of Electrocatalytic Films: Fast Catalysis Regimes

Abstract

AbstractUnderstanding how electrocatalytic films function is of considerable current interest in view of modern energy and analytical challenges. Application of cyclic voltammetry to the analysis of these systems is a worthy alternative to steady‐state techniques in terms of simplicity and rapidity of the current–potential curve recording and the larger extent by which the rate of substrate diffusion may be varied through the rate of potential scanning. The interplay between catalytic reaction, diffusive permeation of the substrate, and diffusion‐like transport of charge is analyzed for fast catalytic reactions as a function of two dimensionless parameters. Procedures for determining the kinetic constants that govern the responses and, particularly, the rate of the catalytic reaction, ensue, based upon on the variations observed when changing scan rate, substrate concentration, and film thickness. These analyses also provide a basis for rational benchmarking of catalysts.