Abstract: TiO₂-SiO₂ composites with large specific surface a reas (up to 308.6 m²/g) were synthesized from wollastonite and titanium sulfate in the absence of any surfactants under finely tuned several experimental conditions. Calcium sulphate, as a faintly soluble substance in water, plays an important role in the formation of pores in the nanocomposites. The microstructure and chemical composition of nanocomposites were characterized by means of X-ray diffractometry, transmission electron microscopy and N₂ adsorption and desorptionanalysis. The as prepared titanium dioxidesilicon dioxide nanocomposites with high specific surface areas and wellcrystallized anatase contents could be used as an efficient photocatalyst.

Key words: TiO₂, SiO₂, wollastonite, porous, calcium sulfate