Preparation of Silica Nanosphere with Vertical Pore and Its Application in Oil-water Separation

Uniform monodispersed mesoporous silica nanospheres with vertical pores were successfully synthesized using chiral amphiphilic small molecule L-16Ala5PyClO(4) and solvents as dual templates via solgel transcription. The morphologies and pore sizes of silicas are adjustable by changing the type and amount of solvents in the reaction systems. With the increase of the organic solvent content, the morphologies of the obtained silica changed from nanospheres with vertical pore structures to nanosheets structures. When 1 mL of benzene, cyclohexane or toluene were used as solvents, only silica nanospheres were obtained, the BET surface areas of silica nanospheres reached 600.7, 669.5, and 560.8 m(2)/g, respectively. The pore sizes were 3.51, 3.54, and 3.46 nm, respectively. Significantly, these ordered silica nanospheres/poly(vinyl alcohol-co-ethylene) (PVA-co-PE) nanofiber membranes have high separation efficiencies (>99%) for n-hexane/water mixtures.