ELECTROCHEMICAL AND PHOTOELECTROCHEMICAL BEHAVIOR OF N-GAAS AND P-GAAS IN THE PRESENCE OF H2O2

The electrochemical and photoelectrochemical behavior of surfaces of (100) n-GaAs and p-GaAs were studied in acid and alkaline solutions containing H2O2. Hydrogen peroxide shifted the flatband potential of p-GaAs, while it did not affect that of n-GaAs. The direction of the shift depended on the pH of the electrolyte: cathodically in acid and anodically in alkaline solution. The reduction of H2O2 in the dark and under illumination was studied by dark current and by photocurrent potential measurements. A mechanism for the decomposition of GaAs at the electrode/electrolyte interface was formulated. © 1990, The Electrochemical Society, Inc. All rights reserved.