A novel composite photocatalyst for water splitting hydrogen production

A novel composite photocatalyst, Pt-TiO2−xNx-WO3 was synthesized by the template method and characterized by X-ray diffraction (XRD), ultraviolet–visible light diffusion spectroscopy (UV–vis), and element analysis. XRD spectra indicated that the photocatalyst was in anatase form and the diagnostic peak for WO3 existed. Combined with the XRD spectra and the results of elemental analysis, the formula of the composite photocatalyst was determined to be Pt-TiO2−xNx-WO3. UV–vis spectra showed the absorption edge was red-shifted to around 750 nm. Under the irradiation of ultraviolet, and with Na2S/Na2SO3 as the sacrificial reagent, the composite photocatalyst showed higher hydrogen production activity than anatase TiO2, and under irradiation with visible light (λ > 400 nm) it showed higher hydrogen production activity than TiO2−xNx while the anatase TiO2 showed negligible activity. An explanation was put forward for the mechanism of the red-shift of the absorption edge and the hydrogen production activity improvement.