CeO_2-Al_2O_3/SiO_2微孔材料的结构及表面特性

STRUCTURES AND SURFACE PROPERTIES OF CERIA AND ALUMINA INCORPORATED INTO MICROPOROUS SILICA MATERIALS

以十二胺(DDA)为模板剂,采用原位掺入法制备了CeO2-Al2O3/SiO2微孔材料,并采用XRD、TEM、N2吸附,TG-DSC等手段对合成样品进行了结构和物性表征,考察了样品在沸水中的水热稳定性。XRD表明,在2θ为2.90处存在一个特征衍射峰,对应的d100值为3.05nm,Ce、Al的掺入引起SiO2骨架结构有序性降低;合成样品具有良好的水热稳定性,经沸水处理48h后仍能保持孔结构。由TEM图可见颗粒成球形。N2吸附分析表明,N2吸附等温线属于LangmuirⅠ型,所得样品的比表面积为635.6m2/g。

Ceria and alumina doped into silica microporous materials were synthesized by in-situ incorporation, using dodecylamine as template. The structures and surface adsorption properties of the sample were investigated by means of XRD, TEM, nitrogen isothermal adsorption and TG-DSC analysis, etc. The results of XRD show that the calcined sample has a single diffraction peak at 2 θ to 2.9° and the corresponding interplanar spacing is 3.05nm. The order of silica decreased evidently when aluminum and cerium were doped into the framework. The sample prepared exhibits high hydrothermal stability, and its microporous structure could be maintained after hydrothermal treatment for 48 hours in boiling water. The monolithic particles with spherical shape could be observed by TEM image. Nitrogen adsorption isotherm plot of the sample recorded belongs to Langmuir I with specific surface area of 570.3m^2/g.