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采用XRD、TPR、XPS技术，分别研究了Co3O4／γ－Al2O3样品的晶相结构、还原性能及表面状态．XRD结果表明，不同前驱物的钴负载于γ－Al2O3后，钴是以Co3O4的结构存在，还原后的钴皆α－Co的形式存在，但以CoCl2为前驱物时，还原后的样品中钴的晶粒较大．TPR结果表明，负载于γ－Al2O3表面的Co3O4出现两个还原峰，这是因为负载于γ－Al2O3表面的Co3O4以晶柱与分散两种状态存在．随着钴负载量的增加，Co3O4的还原峰逐渐向低温移动，钴的还原更加容易．XPS表面分析结果表明，还原后，KCl在催化剂表面富集，覆盖了部分钴而使活性中心Co的数量减少，催化剂的活性下降．由于前驱物不同，使得催化剂表面钴的状态不同．以Co（NO3）2为前驱物的Co3O4／γ－Al2O3样品中，Co3O4与载体之间的相互作用较强；而以CoCl2为前驱物的Co3O4／γ－Al2O3样品，其Co3O4与载体之间的相互作用较弱．钴与载体间的强相互作用不利于肉桂醛分子中羰基的加氢．
The crystal structure, reduction performance and surface state of Co3O4 / γ-Al2O3 samples were investigated by XRD, TPR and XPS techniques. The results of XRD show that the cobalt is present in the form of Co3O4 after the cobalt of different precursors is loaded on γ-Al2O3, and the reduced cobalt is all in the form of α-Co. However, when CoCl2 is used as precursor, cobalt Larger grains. The results of TPR show that there are two reduction peaks of Co3O4 supported on the surface of γ-Al2O3, because Co3O4 supported on the surface of γ-Al2O3 exists in both the column and the dispersed state. With the increase of cobalt loading, the reduction peak of Co3O4 gradually moves to low temperature, and cobalt reduction is easier. The results of XPS analysis showed that after the reduction, KCl was enriched on the surface of the catalyst, covering part of cobalt and reducing the amount of Co in the active site and reducing the activity of the catalyst. Due to the different precursors, the state of cobalt on the catalyst surface is different. In Co3O4 / γ-Al2O3 samples with Co (NO3) 2 as precursor, the interaction between Co3O4 and the support is stronger; while for Co3O4 / γ-Al2O3 with CoCl2 as precursor, the Co3O4 / Interaction is weak. The strong interaction between cobalt and support is not conducive to the hydrogenation of carbonyl groups in cinnamic aldehyde molecules.