Polyvinylalcohol (PVA) induced wormhole-like mesoporous silica nano-fibers

High yield of mesoporous silica nano-fibers has been prepared by a two-phase system in the presence of polyvinylalcohol (PVA), which intensely increased the viscosity of the aqueous phase. Transmission Electron Microscopy (TEM) images show that these fibers possess wormhole-like mesopore architecture and imperfect hexagonal cross sections. The use of PVA made the silica precursor diffusion rate decelerated according to the character of viscosity, thus resulted in the high yield of mesoporous nano-fibers. The fractions of PVA chains co-assembled with the surfactant (cetyltrimethylammonium bromide, CTAB) micelles, and disturbed the hexagonally packed mesochannels, giving rise to the formation of wormhole-like mesopore architecture.