Photoinduced charge property of Ag‐TiO2 films and its relationships with photocatalytic activity under visible illumination

In this article, TiO2 films were synthesized by traditional spin coating method. To improve their photocatalytic activities, we deposited silver on these films by photodeposition. These films also were characterized by several testing techniques, such as X-ray diffraction, ultraviolet–visible diffuse reflection spectrum, XPS, Raman spectroscopy (Raman), surface photovoltage spectroscopy, and SEM. The activity of different films was evaluated for degrading rhodamine B solution under visible illumination. The effects of AgNO3 solution concentration on photoinduced charge property and photocatalytic activity were investigated. The results show that the Ag-TiO2 film immersed in 10−3 mol·L−1 AgNO3 solution exhibits higher activity, which is in good agreement with the characterization results. The weaker the surface photovoltage spectroscopy signal, the higher the photocatalytic activity. Moreover, the activity of some films is higher than that of international Degussa P-25 TiO2 under visible illumination. Copyright © 2012 John Wiley & Sons, Ltd.