Preparation of nanosized TiO2 powders from hydrolysis of TiCl4

By controlling the hydrolysis of titanium tetrachloride with adding (NH4)(2)SO4 and NH4OH, the preparation process of superfine titania ponder was investigated. As-prepared powders were characterized by XRD,TEM, SAEDand TG-DTA techniques. Both XRD and SAED results showed that anatase phase existed in the sample dried at room temperature under vacuum and its primary particle size was about 3.8nm. When calcined at 400 degrees C for 2h, it was the single anatase phase of titania and its primary particle size increased to 6.8nm, but rutile phase occurred at the temperature over 700 degrees C for 2h.