采用十六烷基三甲基溴化铵(CTAB)作为模板剂,正硅酸乙酯(TEOS)为硅源,在碱性条件下,用低温合成方法合成了有序介孔硅,并以此为硬模板,蔗糖为碳前驱体,采用液相浸渍方法填充碳源,制备出有序介孔碳.通过XRD、TEM、N2吸附-脱附等测试方法对其表征,结果表明合成的介孔材料高度有序,均具有很高的比表面积(介孔硅,992～1096 m2/g;介孔碳,930～1208 m2/g),较大的孔容和较窄的孔径分布.还发现随着反应温度的升高,介孔硅的结构从二维六方相(p6mm)转变为三维立方相(Ia3d);介孔碳在复制介孔硅后,其结构也从三维立方相(Ia3d)转变为四方相(I41/a),并对相转变机理做了初步探讨.%Mesoporous silica materials have been synthesized at low temperature under alkaline condition using tetraethyl orthosilicate as the silica source and cetyltrimethylammonium bromide as the structure directing agent. And the ordered mesoporous carbon was synthesized by liquid impregnation method with sucrose as the carbon precursor and mesoporous silica as template. The resulting materials were characterized by X-ray diffraction, transmission electron microscopy and N2 adsorption-desorption. The results show that the mesoporous materials have highly ordered structure, high specific surface area (mesoporous silica, 992～1096 m2/g; mesoporous carbon, 930～1208 m2/g), large pore volume and narrow pore size distribution. In addition, with the rising of reaction temperature, the phase transformation of mesoporous silica from hexagonal p6mm to cubic la3d was observed, and the structure of mesoporous carbon replicated from silica template transformed from cubic la3d to tetragona1141/a. The preliminary discussion on phase transition was carried on.
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