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采用多元醇法合成了一系列具有立方萤石结构的介孔Ce0.5Zr0.5O2(m-Ce0.5Zr0.5O2)复合氧化物,考察了前驱物和PVP浓度、反应时间、焙烧温度和时间等条件对m-Ce0.5Zr0.5O2复合氧化物性能的影响,并运用XRD、Raman、BET、FT-IR和TG等手段对样品进行了表征。结果表明,制备条件对m-Ce0.5Zr0.5O2复合氧化物的性能具有较大的影响,在前驱物和PVP浓度为0.04 M和0.16 M、反应时间7 h、焙烧温度和时间为673 K和4 h时,所制m-Ce0.5Zr0.5O2的性能最好,其比表面积、孔容和平均孔径分别为181 m2.g-1、0.282 cm3.g-1和3.75 nm。活性的测定结果表明,富氢条件下CuO/m-Ce0.5Zr0.5O2催化剂的CO氧化活性比CuO/cp-Ce0.5Zr0.5O2催化剂有较大幅度的提高.
A series of mesoporous Ce0.5Zr0.5O2 (m-Ce0.5Zr0.5O2) composite oxides with cubic fluorite structure were synthesized by polyhydric alcohol method. The concentration of precursor and PVP, reaction time, calcination temperature and time Conditions on the properties of m-Ce0.5Zr0.5O2 composite oxide, and the samples were characterized by XRD, Raman, BET, FT-IR and TG. The results show that the preparation conditions have a great influence on the properties of m-Ce0.5Zr0.5O2 composite oxide. When the precursor and PVP concentrations are 0.04 M and 0.16 M, the reaction time is 7 h, the calcination temperature and time are 673 K and 4 h, the prepared m-Ce0.5Zr0.5O2 has the best performance. The specific surface area, pore volume and average pore diameter are 181 m2.g-1, 0.228 cm3.g-1 and 3.75 nm, respectively. The results of activity measurement show that the CO oxidation activity of CuO / m-Ce0.5Zr0.5O2 catalyst is higher than that of CuO / cp-Ce0.5Zr0.5O2 catalyst under hydrogen enrichment condition.