Synthesis and characterization of mesoporous titania and silica-titania materials by urea templated sol-gel reactions

Mesoporous titania and mesoporous silica-titania materials have been succes sfully synthesized by using organic compound urea as template (or pore-form ing agent) via sol-gel reactions of tetrabutyl titanate alone and with tetr aethyl orthosilicate, respectively, followed by removing the urea by extrac tion with water. The pore parameters and morphology were characterized by N -2 adsorption-desorption measurement, powder X-ray diffraction and transmis sion electron microscopy. The pore diameters of synthesized titania, tip to 5.5 nm, were larger than those mesoporous titania materials prepared by ot her nonsurfactant compounds reported previously by us. The pore diameters o f silica-titania materials decreased with the increase of Si/Ti ratio from 1/100 to 2/1 under the same template concentration. (C) 2001 Elsevier Scien ce B.V. All rights reserved.