Photoinduced hydrophilicity of TiO(2) film as the effect of H(2)O(2) addition

Abstract

TiO(2) thin film photocatalysts coated onto glass plates were prepared by thermal decomposition of tetraisopropyl orthotitanate with a dip-coating process. In this Letter, the mechanism for photoinduced hydrophilicity of TiO(2) film is clarified by adding the extra H(2)O(2) on TiO(2) surface. Results show that the photoinduced hydrophilicity of TiO(2) film is inhibited with the presence of H(2)O(2). The amount of Ti-OH bonds on the surface oppositely increased by the addition of H(2)O(2). It indicates the photoinduced hydrophilicity of TiO(2) results from surface oxygen vacancy, not Ti-OH bonds.