Novel sol–gel preparation of V-TiO2 films for the photocatalytic oxidation of ethanol in air

Abstract

Abstract A series of vanadium-doped TiO 2 catalysts were synthesized by a novel non-aqueous sol–gel method. Ammonium metavanadate was used as dopant source and diethanolamine as chelating agent. The effect on the crystallization, optical properties and photocatalytic activity of the doped TiO 2 films was investigated. Furthermore, to identify the effective composition of the samples, they were characterized by X-ray photoelectron spectroscopy (XPS). The characterization reveals the presence of some N originating from the chelating agent in all samples and confirms V incorporation into the doped samples. Undoped TiO 2 shows high activity under UV + visible and only visible illumination due to the presence of nitrogen. Among the V doped catalysts, the 1 wt.% doped film exhibited the highest photocatalytic activity. This synthetic method leads to V doped titania catalysts which performed much better and in which vanadium ions are more homogeneously distributed than V doped samples synthesized using V 2 O 5 and vanadium alkoxide as V dopant sources. The V + N doped TiO 2 films yield higher activity than single V doped films, but lower than the single N doped TiO 2 film. The co-doping of films requires tuning of concentrations to optimize the photocatalytic activity.