Importance of surface reactions in the photochemistry of ZnS colloids

Abstract

The photochemistry of colloidal ZnS has been studied under a variety of experimental conditions. The time dependence of the photocorrosion has been examined by using time-resolved fluorescence, static fluorescence, and electron spectroscopy for chemical analysis (ESCA) techniques. A qualitative model for the semiconductor and its electrolyte interface is developed to explain the experimental observations where elemental Zn, S, and SO42- formed on the surface act as e-/h+ recombination centers. The photocorrosion products have been identified as SO42-, SO32-, and S. The importance of the surface chemistry in the photochemistry is shown via the correlation between the growth in the emission in..