Synthesis of large-pore SBA-15 silica from tetramethyl orthosilicate using triisopropylbenzene as micelle expander

Abstract

The low temperature synthesis of large-pore SBA-15 silicas with two-dimensional (2-D) hexagonal structure was elaborated using tetramethyl orthosilicate (TMOS) as a silica source, Pluronic P123 (EO 20PO 70EO 20) triblock copolymer as a template, and 1,3,5-triisopropylbenzene as a micelle expander. The adjustment of the initial synthesis temperature, the hydrothermal treatment time and the amount of the swelling agent allowed us to obtain well-ordered SBA-15 (with three or more peaks on small-angle X-ray scattering patterns) with (1 0 0) interplanar spacings tunable in the range from 15 to 22 nm and with pore diameters up to 21 nm. These materials exhibited narrow pore size distributions and large pore volumes (above 1 cm 3 g −1).