Enhanced photocatalytic activity of silver-doped nanoparticulate TiO2 thin films with respect to the method of doping

摘要

A nanoparticle photocatalysts based on silver-doped titanium dioxide were synthesized using a modified sol-gel route and also a dip-and-pull step photochemical method. The catalysts were characterized by UV/Vis absorption spectroscopy, atomic force microscopy, X-ray photoelectron spectroscopy, electron microprobe analysis, and Raman spectroscopy. The effects of the experimental parameters on the photoreactivity of the catalysts were evaluated for the decolorization of Rhodamine B in water and by photoelectrochemistry. The activity results show that silver doping significantly promotes the photoreactivity of the titanium dioxide catalyst with some phase transformation from anatase to brookite. The enhanced photoactivity of new nanoparticulate photocatalysts is predominantly attributable to an improvement in crystallinity, band gap lowering, the nature of precursor materials used, and also the method of doping.