Preparation and characteristics of core-shell rutile titania/wollastonite at room temperature

TiO2/wollastonite composites with core-shell structure were prepared at room temperature. The size of the core, wollastonite, was ca. 200-300 nm and a film of rutile TiO2 with thickness of ca. 10-20 nm coated around the core. Samples were successfully prepared by dissolving the amorphous TiO2 of TiO2/wollastonite in HNO3 solution and then directly re-precipitating rutile TiO2 onto the surface of wollastonite with introduction of induced matter SnO2. When content of SnO2 surpassed 18%, we could obtain complete rutile TiO2/wollastonite; while lower than 12% anatase TiO2/wollastonite would be synthesized. (C) 2003 Elsevier B.V. All rights reserved.