Photoinduced charge property of Ag‐TiO 2 films and its relationships with photocatalytic activity under visible illumination

In this article, TiO 2 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 AgNO 3 solution concentration on photoinduced charge property and photocatalytic activity were investigated. The results show that the Ag‐TiO 2 film immersed in 10 −3 mol·L −1 AgNO 3 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 TiO 2 under visible illumination. Copyright © 2012 John Wiley & Sons, Ltd.