极稀溶液体系中自组装合成纳米介孔氧化硅及其铝修饰材料

Preparation of Nano-sized Mesoporous Silica Dioxide and Al-doped Silica Dioxide at Extremely Low Reactant Concentration

在极稀溶液中,通过改变反应溶剂去离子水的量或原料中铝源的量,可控合成了不同粒径(20～70nm)、形貌和孔道结构的纳米介孔氧化硅颗粒和纳米介孔铝掺杂氧化硅材料.这种材料具有高比表面积(BET比表面积1000 m2/g)和较大的孔容(1.1～1.8 cm3/g).反应物浓度降低或反应物中添加铝源后,介孔材料的有序性下降,粒径减小,孔容增大,并产生大量的间隙孔.通过小角X射线衍射(SAXRD)、透射电镜和氮气吸附-脱附实验表征了样品.

Syntheses of nano-sized mesoporous silica dioxide and that with Al doped were preformed at extremely low reactant concentration, and the products were controllable in size （20-70 nm） , morphology and pore structure by changing the amount of deionized water or Al source in the reaction. The samples were of high BET surface area（more than 1000 m^2/g） and pore volume（ 1.1-1.8 cm^3/g）. The pore structure became less ordered, the particle size decreased, the pore volume increased and a certain accumulation of holes appeared when decreasing reactants concentration or introducing Al source in the reaction. The nano-sized mesoporous samples were characterized by transmission electron microscopy （TEM）, small-angle X-ray diffraction, and nitrogen adsorption/desorpfion techniques.