Influence of the Crystallization Process on the Photoelectrochemical Behaviour of Anodic TiO_2 Films

摘要

On the basis of kinetic and photoelectrochemical studies we show that the formation of amorphous or strongly disordered TiO_2 films on electropolished titanium rods can occur upon anodization in 0.5 M H_2SO_4 solution in a range of thickness which depends on the anodization rate. This finding is confirmed both by the changes in the shape of the photocurrent vs. Potential curves with the energy of the incident photons, and by the impedance behaviour of the junction. Our data indicate that TiO_2 films having different degree of disorder are formed depending on the anodiza- Tion rate and oxide thickness.