[Background irradiated photocatalysis of TiO2 thin films]

In terms of the UV irradiating directions, photocatalysis with TiO2 thin films can be divided into two types, the background irradiated photocatalysis and the foreground irradiated one. Comparatively, background irradiated photocatalysis has an advantage of avoiding the UV light attenuation which foreground irradiated one suffers when the light is going through the solution. In this article, the influence of the thickness of the films, the wavelength of light source and non-uninformly doping with V on the photocatalytic efficiency of the catalyst in case of background irradiated photocatalysis is investigated, and simultaneously it is compared with foreground irradiated one. The results show that in case of background irradiated photocatalysis there is an optimal thickness of the film according to the wavelength of the light source that is limited in the range of 300 nm to 388 nm, which is quite different from foreground irradiated one. But in both cases, the catalyst's photocatalytic activities are improved by non-uniformly doped with V.