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研究了以纯单斜（ｍ）和四方（ｔ）晶相ＺｒＯ２为催化剂的ＣＯ加氢反应．尽管两种晶相催化剂均有较高的低碳烯烃的选择性，但是也发现了两者催化性能的显著差别．ｍ－ＺｒＯ２催化剂对异丁烯有突出的选择性，而ｔ－ＺｒＯ２催化剂，则只有乙烯和丙烯，几乎没有Ｃ４烯烃的选择性．室温下ＣＯ吸附的原位ＩＲ谱测试可见，只有在ｔ－ＺｒＯ２催化剂上观测到不可逆含氧吸附物种．吡啶吸附的Ｒａｍａｎ谱显示出它们之间表面性质的差别，ｍ－ＺｒＯ２催化剂表面存在等强度的Ｌｅｗｉｓ和Ｂｒｏｎｓｔｅｄ酸中心，而在ｔ－ＺｒＯ２催化剂表面几乎只有Ｂｒｏｎｓｔｅｄ酸中心．催化过程的一些模型分子电子结构计算也表明了ＺｒＯ２催化剂对低碳烯烃选择性内在的电子结构条件．我们推测ＣＯ在ｍ－ＺｒＯ２催化剂表面的孪式吸附物种可能是导致异丁烯产物的根源
The hydrogenation reaction of CO with pure monoclinic (m) and tetragonal (Zr) as catalyst was investigated. Although both of the two catalysts exhibit higher selectivity to light olefins, significant differences in their catalytic properties have also been found. The m-ZrO2 catalyst has outstanding selectivity to isobutylene, whereas the t-ZrO2 catalyst has only ethylene and propylene with almost no selectivity to C4 olefins. In-situ IR spectra of CO adsorption at room temperature showed that only irreversible oxygen-containing species were observed on the t-ZrO2 catalyst. The Raman spectra of pyridine adsorbed showed the difference of the surface properties between them. There were Lewis and Bronsted acid sites on the surface of m-ZrO2 catalyst with almost the same Bronsted acid sites on the surface of t-ZrO2 catalyst. The calculation of the electronic structure of some model molecules in the catalytic process also indicates the intrinsic electronic structure conditions of the selectivity of ZrO2 for light olefins. We speculate that the twin adsorbed species of CO on the m-ZrO2 catalyst surface may be the source of the isobutene product