PHASE STRUCTURE OF W-DOPED NANO-TiO₂ PRODUCED BY SOL-GEL METHOD

With Ti(OBu)₄ as precursor, and HAc as complexing agent, pure and W-doped TiO₂ gelatins were prepared by a sol-gel method. During the process of gel formation, metal ions were dispersed in the porous TiO₂ matrix. Then, powders of nano-TiO₂ and W-doped nano-TiO₂ were prepared by drying, grinding and heat treatment at different temperatures. The grain size and structure of the samples, pure TiO₂ and W-doped, and treated at different temperatures, were studied by X-ray diffraction (XRD), Beckman Coulter Sorption Analysis and TEM. Results showed that, with increasing temperature, the TiO₂ transformed from anatase to rutile and the grain size increased. This transformation and grain growth of TiO₂ could be retarded by doping with W.