High porosity mesoporous siliceous structures

Abstract

A process comprising: A) contacting one or more of sources of silicon oxide, selected from water soluble.silica sources arid alkali metal silicates, with an aqueous reaction medium, comprising one or more nonionic surfactants and thereby forming mesoporous structures comprising crosslinked silicon oxide units, wherein said crosslinked silicon oxide units have pores of about 1 to about 100 nanometers and wherein the aqueous reaction medium exhibits a pH of about 0 to about 4.0; B) exposing the aqueous reaction medium containing the mesoporous structures to elevated temperatures for a time sufficient to achieve the desired structure and pore size. Preferred water soluble silica sources comprise silicic acid, or polysilicic acids, The aqueous reaction, medium is prepared by combining one or more nonionic surfactants and water, theteby forming an aqueous, reaction medium, comprising micelles. Preferably, the aqueous reaction medium further comprises, a. micelle swelling agent capable of swelling micelles formed by the surfactant in the aqueous reaction medium. In one embodiment the process forms structures with struts comprised of crosslinked silicon oxides which connect at least some of the pore forming structures.