Sonochemical incorporation of nanosized TiO 2 inside mesoporous silica with high photocatalytic performance

Abstract

Highly dispersed of nanosized TiO 2 inside mesoporous silica was reported for the first time by using a sonochemical approach. The amount of TiO 2 inside the pores of SBA-15 has been controlled through the irradiation time. Characterizations by powder X-ray diffraction, nitrogen adsorption–desoprtion, X-ray photoelectron spectra (XPS), UV–vis spectroscopy and Fourier transform infrared (FT-IR) spectra have been carried out to understand the nature of TiO 2 formed inside the pores. At low titania loading of 7–18.5 wt.%, TiO 2 is monoatomically dispersed and the pore size of SBA-15 is not altered. With higher titania loading (28 wt.%), the incorporation of TiO 2 inside the mesopores of SBA-15 results in a slight reduction of the pore size without blocking the pores. The photocatalytic activities of the resultant nanocomposites with titania loading of 28 wt.% were assessed by measuring the percentage degradation of methyl blue (MB) using UV–vis spectroscopy. The results indicate the sample exhibits an improved photocatalytic performance together with a high adsorption capability as compared with that of the commercial P25. This facile strategy may be extended to other metal oxides, with potential high performance in many applications.