Preparation and characterization of Pt(RuO2)/TiO2 catalysts : test in a continuous water photolysis system

Abstract Aqueous suspensions of Pt(RuO 2 )/TiO 2 photocatalysts, where Pt has been reduced by different techniques, have been irradiated with UV light in a photoreactor with a continuous gas phase composed of Ar and photoproducts. The performance of the catalysts in the water-splitting process has been related to these different Pt reduction methods by consideration of the physical characteristics of the powders (deposits and support), such as crystal structure, specific surface area, particle size, quality of the metal dispersion, as well as the oxidation state and doping changes brought about by these techniques. Long-term activity could be studied given the nature of the photoreactor system used, where photoproducts do not build up and steady conditions can be reached. The catalytic role of RuO 2 has been specifically studied in connection with the preparative treatments followed.