The purpose of this research was to study phase transformation and photocatalytic properties of TiO2powders. TiO2powders were prepared by microwave-assisted sol-gel method. The prepared powders were refluxed at 18 W to 450 W for 1 h and dried at 180 W for 1 h by a conventional microwave oven. The phase transformations of powders were characterized by XRD and photocatalytic activities of powders were evaluated by UV-Vis spectrophotometer. The results show all samples reveal that only the anatase phase and has the crystallite size is 13.8, 10.3 and 9.2 nm when the refluxed at 180, 300 and 450 W. It was found that TiO2powders refluxed at 450 W were found to give the highest photocatalytic efficiency is about 90.06% under UV irradiation for 6 h.
