Abstract
We report on the facile synthesis of SiO(2) @nitrized-TiO(2) nanocomposite (NST) by calcination of TiO(2) xerogel with OctaAmmonium POSS® (N-POSS; POSS=polyhedral oligomeric silsesquioxanes). The as-obtained nanoporous mixed oxide is constituted by uniformly distributed SiO(2) and nitrized-TiO(2) , where the silica component is present in an amorphous state and TiO(2) in an anatase/rutile mixed phase (92.1 % vs. 7.9 %, respectively) with very small anatase crystallites (3.7 nm). The TiO(2) lattice is nitrized both at interstitial and substitutional positions. NST features a negatively charged surface with a remarkable surface area (406 m(2) g(-1) ), endowed with special adsorption capabilities towards cationic dyes. Its photocatalytic behavior was tested by following the degradation of standard aqueous methylene blue and methyl orange solutions under UV and visible light irradiation, according to ISO 10678:2010. For comparison, analogous investigations were carried out on a silica-free N-TiO(2) , obtained by using NH(4) Cl as nitrogen source.