Cyclic Voltammetry of Metal Alloys Dissolution Facilitated by a Homogeneous Follow Up Chemical Reaction

This work presents a theoretical analysis of cyclic voltammetry (CV) for electrode processes involving the dissolution of metal alloys coupled with a homogeneous follow-up chemical reaction in solution (see the reaction scheme). The model describes a modified EC-type mechanism, where the initial electron transfer from the metallic surface to the electrolyte generates a transient species that undergoes a subsequent homogeneous reaction, influencing both the anodic and cathodic current responses. Analytical and numerical simulations were employed to examine the effect of kinetic parameters, such as the chemical rate constant, equilibrium constant, and diffusion coefficients, on the shape and position of voltammetric peaks. Particular emphasis is placed on the diagnostic criteria that distinguish simple electrochemical dissolution from dissolution–reaction sequences, including peak asymmetry, hysteresis behavior, and potential-dependent current amplification. The theoretical framework provides fundamental insight into coupling phenomena relevant to alloy corrosion, passivation, and electrocatalytic dissolution processes.
Rection scheme of this mechanism is:
M(solid) - ne- = Mn+(aq);
Mn+(aq) + Y(aq) = MY(aq)