Direct synthesis of sulfonic acid-functionalized periodic mesoporous benzene–silicas with large pores

Abstract

Periodic mesoporous benzene–silicas containing sulfonic acid groups were directly synthesized by the co-condensation of 1,4- bis (triethoxysilyl) benzene organosilica precursor and 3-mercaptopropyltrimethoxysilane (MeO) 3Si(CH 2) 3SH in the presence of H 2O 2 using non-ionic block copolymer templates such as a Pluronic P123 (EO 20PO 70EO 20) and poly(ethylene oxide)–poly( dl-lactic acid- co-glycolic acid)–poly(ethylene oxide) (EO 16(L 29G 7)EO 16) under low acidic conditions. The sulfonic acid functional groups (–SO 3H) were generated in situ by the oxidation of the propylthiol using H 2O 2 as an oxidant during the sol–gel synthetic process, which was observed by FT-IR and solid-state 13C NMR spectroscopy. Well-defined 2D hexagonal ( p6 mm) mesostructures were also observed using BET, TEM, and SAXS measurements. The sulfonated mesoporous benzene–silicas prepared in this study also exhibit spherical macrostructures with diameters of 2–5 μm.