Tunstophosphoric acid immobilized on core-shell silica-titania microspheres with visible light absorption for the photodegradation of 4-chlorophenol

GUSTAVO PABLO ROMANELLI,; MARÍA DE LOS ÁNGELES ORELLANA; LUIS RENÉ PIZZIO; LILIAN OSIGLIO

Madrid

Simposio; 3rd International Symposium on Catalysis for Clean Energy and Sustainable Chemistry; 2016

TiO2 has been the most widely used photocatalysts because it is easily available, inexpensive, nontoxic, and shows relatively high chemical stability. It is reported that titania performance in the photodegradation of contaminants contained in wastes depends on the crystal structure, the crystallinity, the surface area, the band gap energy, and the morphology, among other factors. The low surface area and the fast recombination of the photoinduced electrons and holes are the main effects that can lead to a low photocatalytic activity.Composites based on silica and titania, can have the photocatalytic properties from titania and the high stability from silica In the last years, the synthesis of shell and core-shell particles (@TiO2 and SiO2@TiO2 respectivelly) has attracted much attention due to their large surface area, low density, and highly efficient light-harvesting properties. Additionally, shell and core-shell materials may be less harmful to biological systems than TiO2 nanoparticles.Tungstophosphoric and tungstosilícic acid (TPA and TSA respectively) were employed to modify TiO2 in order to reduce the charge recombination and to enhance the visible light absorption. We report here the shynthesis and characterization of silica-titania core-shell microspheres modified with TPA. The influence of some preparati