A visible light-sensitive tungsten carbide/tungsten trioxde composite photocatalyst

A photocatalyst composed of tungsten carbide (WC) and tungsten oxide (WO(3)) has been prepared by the mechanical mixing of each powder. Its photocatalytic activity was evaluated by the gaseous isopropyl alcohol decomposition process. The photocatalyst showed high visible light photocatalytic activity with a quantum efficiency of 3.2% for 400-530 nm light. The photocatalytic mechanism was explained by means of enhanced oxygen reduction reaction due to WC, which may serve as a multielectron reduction catalyst, as well as the photogeneration of holes in the valence band of WO(3). (c) 2008 American Institute of Physics.