Genuine anodic and cathodic current components in cyclic voltammetry

Abstract

Implicit anodic and cathodic current components associated with the real net current at a given potential of a simple quasireversible electrode reaction can be accurately estimated using basic mathematical modeling within the framework of Butler-Volmer electrode kinetics. This methodology requires only prior knowledge of the formal potential of the dissolved redox couple, offering direct insight into the electrode kinetics. The proposed approach facilitates a unique transformation of a conventional cyclic voltammogram, allowing the replacement of the common, net current with authentic anodic and cathodic current components. This simple methodology introduces a novel perspective in analyzing voltammetric data, particularly enabling the kinetic characterization of fast, seemingly electrochemically reversible electrode processes on macroscopic electrodes at slow scan rates. Theoretical predictions are experimentally demonstrated using the electrode reaction for the reduction of the hexaammineruthenium(III) complex, serving as an example of one of the fastest electrode processes involving a dissolved redox species.