【摘要】 通过Mo(CO) 6的热分解制备了Al2 O3 薄膜负载的金属钼模型催化剂,并采用热脱附谱(TDS)和X射线光电子能谱(XPS)原位研究了CO在金属态Mo/Al2 O3 模型催化剂表面的化学吸附.结果表明,在低温下CO可与Al2 O3 表面的金属钼纳米粒子发生多重配位形成类似于羰基钼的物种.CO在Mo/Al2 O3 模型催化剂表面的吸附导致Mo 3dXPS峰向高结合能方向位移,所生成的羰基钼物种表现为TDS谱中在2 4 0K处有脱附峰.负载的金属钼模型表面与体相金属钼的化学性质完全不同,表现出明显的粒子尺寸效应更多还原

【Abstract】 The thin alumina film-supported metallic molybdenum model catalyst was prepared by thermal decomposition of Mo（CO）₆, and CO chemisorption on the catalyst was investigated in-situ by thermal desorption spectroscopy （TDS） and X-ray photoelectron spectroscopy （XPS）. The results showed that a molybdenum-carbonyl-like species was formed on the alumina surface at low temperature by high coordination of CO with the surface metallic molybdenum nanoparticles, indicating a reversible regeneration of molybdenum carbonyl on the alumina surface. CO chemisorption on the model catalyst surface caused the Mo 3 d XPS peak to shift toward higher binding energy. The formed molybdenum carbonyl species appeared at about 240 K in the TDS. The supported metallic molybdenum nanoparticles were quite different from the bulk molybdenum in chemical properties, which indicated a prominent particle-size effect of the clusters.更多还原