Electrochemical Kinetics of Diffusion Problems with a Moving Phase Boundary

Abstract

The growth and dissolution of nuclei and a deposit film on a solid electrode are considered. The diffusion problems of the growth and dissolution of hemispherical nuclei and a thin deposit film are solved. Equations are derived to describe the I–V characteristics and chronoamperograms of reversible, irreversible, and quasi-reversible electrode processes, and the dependences of the peak current, the amount of deposit on an electrode, the potential of the peak current, and the full width at half-maximum of an I–V characteristic on the preelectrolysis parameters are determined. The formation of a new phase at the solid–solution interface and the mass-exchange processes at the weakly soluble film–solution interface are discussed. Anodic films are experimentally studied. In the case of nuclei or a thin anodic film, the amount of compound formed on the electrode surface linearly depends on the ionic concentration and the preelectrolysis time.