以硝酸铈、硝酸锆为无机源,十六烷基三甲基溴化铵(CTAB)为模板剂.采用水热法制备了介孔Ce_xZr_(1-x)O_2固溶体,考察了n(CTAB)/(n(Ce)+n(Zr))及铈锆物质的量比对其结构的影响.通过X射线衍射(XRD)、N_2吸附脱附、高分辨透射电镜(HRTEM)、FT-IR分析手段对其结构进行了表征.结果表明,n(CTAB)/(n(Ce)+n(Zr))对样品结构有很大影响,在优化条件下.合成的Ce_xZr_(1-x)O2固溶体具有与CeO_2相似的立方萤石结构;采用两步焙烧法去除模板剂后,HRTEM显示样品是由纳米粒子堆积而成,并具有孔道结构;介孔Ce_(0.5)Zr_(0.5)O_2的比表面积为175m~2/g,平均孔径和孔体积分别是5.9nm和0.257cm3/g;Ce~(0.75)Zr_(0.25)O_2的比表面积为110m~2/g,平均孔径和孔体积分别为9.4nm和0.261cm~3/g.
Mesoporous Ce_xZr_(1-x)Q_2 solid solutions is synthesized by hydrothermal method using cerium nitrate and zirconium nitrate as inorganic species, CTAB as surfactant, respectively. The influence, on textural, structural properties are investigated, such as the molar ratio of n(CTAB)/(n(Ce)+n(Zr))and composition(i. e Ce/Zr ratio). The samples are characterized by XRD, N_2 adsorption-desorption, HRTEM and FTIR techniques. The results show that the molar ratio of n(CTAB)/(n(Ce)+n(Zr)) greatly affect structural properties. Under the optimum synthesis conditions, Ce_xZr_(1-x)O_2 with the cubic fluorite-structure similar to CeO_2;After removing the template agent by two-step calcination method, HRTEM results show that the sample is formed by the accumulation of nano-particles with the pore structure. The surface area of mesoporous Ce_(0.5)Zr_(0.5)O_2 is 175m~2/g, the average pore diameter and total pore volume are 5. 9nm and 0. 257cm~3/g respectively; the specific surface area of Ce_(0.75) Zr_(0.25) O_2 is 110m~2/g, the average pore diameter and total pore volume are 9. 4nm and 0. 261cm~3/g , respectively.
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