Structure influence of Fe3+ doped TiO2/SiO2 film on the photocatalytic properties

Fe3+ ion doped titanium dioxide films coated on silica (Fe3+ -TiO2/SiO2) were prepared by sol-gel method. The obtained films were more effective than TiO2 nano-size powder in decomposing Rhodamine B under irridation with Xe lamp. In the Fe3+ doping system, the optimum value of the Fe3+/Ti4+ (atomic ratio) was 0.03% for the photocatalytic degradation of Rhodamin B. The experimental results suggested that the photocatalytic reactions with the titanium dioxide nanosize powder and film as the catalyst proceed in two different degradation mechnisms. By the characterization using XRD, SEM, Raman, and FTIR technologies, we can conclude that the surface layer structure of TiO2 film on silica and the formation of Ti-O-Si bond play important roles with the increasing of degradation efficiency, and result in two different decomposition mechanisms for film and power.