Periodic Mesoporous Organosilicas with Domain Functionality: Synthesis and Advanced Characterization

Abstract

Bifunctional periodic mesoporous organosilicas (PMOs) with —CH2—CH2—/—CH═CH— bridges have been synthesized using a salt assisted nonionic templating method. The ability to direct locations of the individual organic groups using a novel silica precursor prehydrolysis step is demonstrated. Depending on the prehydrolysis conditions the products showed either structural heterogeneities consisting of domains of the same functionality or a structurally homogeneous system, confirmed by 1H−29Si heteronuclear correlation (HETCOR) experiments. The resulting PMOs show large pore volumes (up to 1.34 cm3 g−1) and high surface areas (up to 1310 m2 g−1). The ability to form domain structures within the same mesostructure may have potential applications in molecular recognition and separation.