Synthesis of titania-silica xerogels by co-solvent induced gelation at ambient temperature

A series of binary titania-silica mixed oxides was prepared by sol-gel synthesis at room temperature. The hydrolysis of titanium isopropoxide (Ti((OPr)-O-i)(4)) and tetraethylorthosilicate (TEOS) was facilitated by co-solvent induced gelation in acidic media. The resulting gels were dried, calcined, and then characterized by powder X-ray diffraction analysis, nitrogen sorption studies (at 77 K), diffuse reflectance spectroscopy, Raman microscopy, and transmission electron microscopy. The nitrogen sorption studies indicate that the porosities could be tuned when simple aromatic solvents such as toluene, p-xylene, or mesitylene were added as a co-solvent to the synthesis gel. The binary mixed metal oxide materials obtained in this study showed high activity towards the degradation of phenol, and possessed high surface areas, and large pore volumes with narrow pore size distribution without the need for additional hydrothermal synthesis or supercritical drying. (C) 2011 Elsevier B.V. All rights reserved.