Synthesis of TiO2 (anatase) by sol-gel process performed in metal chlorides saturated aqueous solutions

Titania powders were synthesized by a sol-gel process using titanium tetrab utoxide as a precursor. The syntheses were performed in water or in saturat ed aqueous solutions of KCI, CaCl2, NiCl2, CoCl2, and MnCl2. It is demonstr ated, by X-ray diffraction patterns of the synthesized powders that the sam ples obtained in saturated aqueous solutions of metal chlorides are crystal line (anatase phase) with some minor amount of brookite phase, whereas the sample synthesized in water is amorphous in nature. Thus, it is shown that the anatase phase can be obtained independently on any previous or further treatment of the synthesized powder, such as hydrothermal or heat treatment , providing a new, simple, quick, and inexpensive route to synthesize anata se powders. (C) 2001 Academic Press.