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Mesoporous titania–silica composite (MTSC) with a large surface area (387 m2/g) and large pore volume was
synthesized by a two step condensation sol–gel method. Transparent TiO2 sol was formed at room temperature
through condensation and peptization of titanium oxychloride solution using ammonium hydroxide and
aqueous nitric acid respectively. Sodium silicate was used as a silica source to form a composite with the preformed
TiO2 sol. The physical properties of the composite were examined by Fourier Transform infrared
(FTIR), BET surface area, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), transmission
electron microscopy (TEM) and X-ray diffraction (XRD). The nitrogen physisorption behavior of the synthesized
composite was compared to that obtained from grafting and one-pot co-condensation methods
using the same precursors in the presence of cetyltrimethylammonium bromide (CTAB). It was found that
MTSC synthesized under this method possessed large pore sizes and pore volume but its thermal stability
was comparatively low. FTIR spectra showed the formation of a Ti\O\Si bond at 940 cm−1 suggesting
that titania was incorporated in silica to form a composite. The XRD patterns showed that the major phase
of the titania had an anatase phase up to 900 °C but it transforms into rutile when calcined at 1000 °C. Furthermore
the EDS studies of the as-synthesized and calcined samples substantiated the formation of titania–silica
composites.