Coulostatic pulse relaxation at the TiO2 (single crystal)/electrolyte solution interface

Abstract

The relaxation ofcoulostatic pulses at the TiO2 (single crystal)/electrolyte solution interface is analyzed in terms of an equivalent circuit which distinguishes among the capacity of the semiconductor space charge, the capacity of surface states, two adsorption capacities, and a diffusion process in the liquid phase. The semiconductor space charge capacity is characterized by a Mott-Schottky-like dependence on the potential drop over the interface; it can be used to calculate the donor concentration and the fiat band potential. The latter shifts to more negative values (toward SCE) with increasing pH.