Periodic mesoporous organosilicas with domain functionality: Synthesis and advanced characterization

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 H-1-Si-29 heteronuclear correlation (HETCOR) experiments. The resulting PMOs show large pore volumes (up to 1.34 cm(3) g(-1)) and high surface areas (up to 1310 m(2) g(-1)). The ability to form domain structures within the same mesostructure may have potential applications in molecular recognition and separation.