The oscillatory reduction of hydrogen peroxide on an n-type gallium arsenide electrode was studied by means of the electrolyte electroreflectance technique. It is found that during the current oscillations both the reflectivity and electroreflectance oscillate with qualitatively different patterns. A simple model, which attributes the current oscillations to an anomalous dependence of the band bending in the semiconductor depletion layer on the potential drop across the semiconductor/electrolyte interface, is considered for comparison. It is concluded that the absolute reflectivity detects a slow variable of the system, most likely related to the chemical composition of the surface, and the electroreflectance detects a fast variable of the system, most likely related to the interfacial potential distribution.

Scanning Microscope for Semiconductor Characterization (SMSC): Study of the Influence of Surface Morphology on the Photoelectrochemical Behavior of an n-MoSe2 Single Crystal Electrode by Photocurrent and Electrolyte Electroreflectance Imaging.-Comparative studies on as-grown, photoelectrochemically aged, and on " peeled" n-MoSe2 single crystals, the upper layers of which are freshly peeled off, give complementary information on the semiconductor/ electrolyte interface in relation to the semiconductor topology. Major changes in the photoelectrochemical behavior after electrode aging are due to the detrimental effect of electrochemical corrosion. The effects of aging are explained in terms of the high anisotropy and structural parameters of n-MoSe2 crystals. -(MARTINEZ CHAPARRO, A.; SALVADOR, P.; MIR, A.; J.

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