Electron Excitation and Chemical Steps during Anodic Decomposition of n‐GaAs Electrodes: A Hole Injection Study

The contribution of electron excitation to the anodic dissolution of the n-GaAs electrode was studied quantitatively by measuring the increase in the anodic blocking current when hole-injecting agents such as Ce4+ or Fe(CN)3−6 were added to the electrolyte solution. The experimental relationship between the anodic current and the cathodic hole injection current was interpreted on the basis of the anodic decomposition mechanism, including a chemical step, proposed previously to explain stabilization results. This mechanism is complemented by an electrochemical step involving electron excitation from a decomposition intermediate occurring in parallel to the chemical step.