Platinization of sunlight active Ti–W mixed oxide photocatalysts

The photocatalytic effects of the platinization on sunlight-active nanosize Ti–W mixed oxide materials with anatase structure were investigated. Platinization was shown to promote the photocatalytic mineralization of toluene, leading to an enhanced reaction rate of ca. 2.3 with respect to the parent Ti–W mixed oxide. This reaction rate increase is significantly higher than that obtained using ultraviolet excitation for titania-based oxides in the degradation of toluene and seems intimately related to the presence of PtO bonds located at the platinum–anatase interface. The chemical/physical bases of such behavior are discussed on the light of a structural/electronic characterization of the solids with the help of X-ray diffraction and Raman/UV–visible spectroscopy, along with additional in situ experiments run under sunlight excitation using infrared and electron paramagnetic resonance spectroscopy.