Direct growth of F-doped TiO2 particulate thin films with high photocatalytic activity for environmental applications

Here we report on a novel and facile approach to directly grow F-doped TiO2 particulate thin films with superb visible light photoelectrical response and high photocatalytic efficiency by oxidizing titanium plates in the presence of H2O vapor assisted with NaF at relatively low temperatures. The effects of the oxidation temperature and the amount of the NaF coated on the titanium plates on the morphology and the photocatalytic properties of the formed F-doped TiO2 particulate thin films have been investigated. The formed F-doped TiO2 particulate thin films show a significant increase in the photocurrent of photoinduced splitting of water into hydrogen and oxygen compared with that of commercial P-25 TiO2, under irradiation of either UV or visible light. In addition, the photocatalytic activity of the formed F-doped TiO2 particulate thin films out perform the commercial P-25 TiO2 for the photodegradation of 4-nitrophenol under UV and visible light irradiation. The approach described in this study can be easily commercialized to fabricate F-doped TiO2 particulate thin films on a large-scale for very promising environmental applications in the photodegradation of organic pollutants and photoinduced splitting of water into hydrogen, a green energy source. (C) 2007 Elsevier B.V. All rights reserved.