Microwave-assisted synthesis of periodic mesoporous organosilicas with ethane and disulfide groups

Ethane and disulfide-bridged periodic mesoporous organosilicas have been synthesized under microwave conditions. These materials were obtained by co-condensation of 1,2-bis(triethoxysilyl)ethane and bis(triethoxysilylpropyl) disulfide organosilica precursors and poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymer template under weakly acidic conditions. Incorporation of bridging groups into the framework and the presence of ordered mesopores were confirmed by nitrogen adsorption at -196 degrees C, transmission electron microscopy (TEM), elemental analysis, and powder X-ray diffraction. The resulting organosilica samples have the specific surface area, single-point pore volume and pore width in the ranges of 960-1220 m(2)/g, 1.14-1.56 cm(3)/g, and 7.1-8.4 nm, respectively. TEM images show domains of hexagonally ordered mesopores in these samples, although this ordering is much less pronounced as in the case of purely siliceous SBA-15. (C) 2008 Elsevier Inc. All rights reserved.