Probing photochemical transformations at TiO2/Pt and TiO2/Ir interfaces using x-ray absorption spectroscopy

Structural transformations at the TiO2∕Pt and TiO2∕Ir interfaces during UV-irradiation have been probed by X-ray absorption spectroscopy. Oxidation by the photogenerated holes results in the intercalation of Pt and Ir into the Titania matrix. The structural transformations observed with Pt and Ir nanoparticles anchored on TiO2 is different than the clustering of gold atoms observed in the TiO2/Au system. Implications of such structural transformations on the photocatalytic activity of semiconductor photocatalyts are discussed.