关键词: 介孔硅, 介孔碳, 相转变

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 di?raction, 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 Ia3d was observed, and the structure of mesoporous carbon replicated from silica template transformed from cubic Ia3d to tetragonal I4₁/a. The preliminary discussion on phase transition was carried on.

Key words: mesoporous silica, mesoporous carbon, phase transition