微波法直接合成Ce/SBA-15介孔分子筛

Direct Synthesis and Characterization of Cerium-Incorporated SBA-15 Mesoporous Molecular Sieve

以三嵌段共聚物(P123)作为模板剂,正硅酸乙酯(TEOS)为硅源,利用溶胶凝胶法,在微波条件下快速地将Ce金属离子直接掺杂到SBA-15介孔分子筛骨架中。通过X射线粉末衍射(XRD)、傅立叶变换红外(FT-IR)、紫外可见漫反射(UV-Vis)、透射电镜(TEM)和N2的等温吸附-脱附法等手段对合成的样品进行表征。结果表明:稀土Ce金属离子以Ce3+,Ce4+两种价态存在于SBA-15介孔分子筛中。合成的Ce/SBA-15分子筛具有规则六方孔道结构,较高的比表面积和孔容(分别为714.85 m2.g-1和0.67 cm3.g-1),其孔半径主要集中在1.8 nm。

Using P123 as a template and TEOS as a source of silica, Ce-silica mesoporous SBA-15-type material was synthesized rapidly via microwave technique and characterized by XRD, FT-IR, DRS and low temperature N2 adsorption-desorption measurements. The results showed that Ce was successfully incorporated into the framework of SBA-15 molecular sieve with the valence of three and four. The synthesized material not only retained the hexagonal order and physical properties of purely siliceous SBA-15 but also possessed the high surface area and the narrow pore-size distribution （714. 85 m2·g^-1 and 0. 67 cm3·g^-1, respectively）. The pore size distribution of Ce/SBA-15 was concentrated at a radius of 1.8 nm.