Functionalized periodic mesoporous organosilica fibers with longitudinal pore architectures under basic conditions

Hierarchically organized functionalized periodic mesoporous organosilica (PMO) fibers with longitudinal pore architectures have been prepared via a simple one-pot synthesis procedure from the co-condensation of 1,2-bis(triethoxysilyl)ethane (BTESE) with either of two kinds of trialkoxysilanes, (3-triethoxysilylpropyl) isocyanate (ICP), or 1-[3-(trimethoxysilyl)propyl] urea (UREDO) under basic conditions. The influence of organosilica source and temperature on the formation and the internal pore architecture of the functionalized PMO fibers were investigated. The pore channels in both types of PMO nanofibers are hexagonally packed, in which pore channels are aligned parallel to fiber axis. The diameters of the fibers range from 50 to 300 nm, and the lengths are up to 7 μm. Electron microscopy and X-ray diffraction investigations were carried out to elucidate the morphological and structural features of the functionalized PMO fibers. The formation of well-condensed and interconnected organosiloxane network was proven by 29Si CP/MAS NMR spectroscopy. How the nature of organic groups has impacted on the surface areas and pore volumes were evaluated by N2 isotherms.