Preparation and characterization of nanosized TiO2 powders from aqueous TiCl4 solution

A solution-based processing method has been used to synthesize nanocrystalline TiO₂ powders by controlling the hydrolysis of TiCl₄ in aqueous solution. As-prepared powder was characterized by TEM, HREM, XRD, BET and ED techniques. In the presence of a small amount sulphate ions, the powder was pure anatase and its primary particle size is finer than that of alkoxide-derived powder, moreover the transformation of anatase to rutile was retarded. Both hydrolysis temperature and amount of sulfate ions had effects on the morphology and crystallization of the powder. In an optimum process, TiO₂ powder in the anatase phase was fabricated without calcination and its primary size was 4nm, BET surface area was 290m²/g.