Abstract:

WO3/TiO2 samples were prepared by sol-gel process and characterized by means of XRD、LRS、TEM、DRS、BET、XPS.It has been shown that the mean crystal diameter and mean particle diameter of WO3/TiO2 samples decreased while the percent of anatase and specific surface area increased owing to the doping of WO3.New LRS peaks presented at 797,967 and 969cm-1,respectively,when the concentration of doped WO3 was 2%,5%and 8%.The reflectance percentate of WO3/TiO2 samples was less than that of pure TiO2 in the range of 380-460nm.The XPS fitting analyses showed that there were W6+、W5+、W4+ and Ti4+、Ti3+ in the lattice of WO3/TiO2.Being a model reaction,the photo-catalytic degradation of methylene blue was investigated in TiO2 and WO3/TiO2 nanopowder suspension irradiated by high-pressure mercury lamp.As a result,the addition of WO3 to TiO2 greatly enhanced its photo-catalytic behavior,and the optimum concentration of WO3 in TiO2 was 2%(molar percent).Moreover,the relationship between photo-activity and the physical and chemical properties of the samples have been discussed.

Key words: Photo-catalysis, Titanium dioxide, Tungsten oxide, Coupled semiconductor, Methylene blue