Onfroy Thomas, Clet Guillaume, Houalla Marwan
Laboratoire de Catalyse et Spectrochimie (UMR CNRS 6506), ENSICAEN-Université de Caen, 6 Bd. du Maréchal Juin, 14050 Caen (Cedex), France.
J Phys Chem B. 2005 Mar 3;109(8):3345-54. doi: 10.1021/jp048435m.
The relationship between the acidity, catalytic activity, and surface structure for tungsten oxide supported on zirconia was investigated for a series of solids prepared by equilibrium adsorption on monoclinic zirconia. The catalysts were active for propanol dehydration only above a threshold in W loading. The acidity was studied by infrared spectroscopy of adsorbed probe molecules (2,6-dimethylpyridine and CO), and the onset of activity was correlated with that of the formation of relatively strong Brønsted acid sites. The variation in the abundance of these sites correlated with the catalytic activity. Lewis sites were present but could not be directly associated with the activity. Raman, IR, and UV spectroscopy results indicated that the active sites were related to polymeric W surface species.
通过在单斜氧化锆上进行平衡吸附制备了一系列固体，研究了氧化锆负载的氧化钨的酸度、催化活性和表面结构之间的关系。这些催化剂仅在钨负载量高于阈值时对丙醇脱水具有活性。通过吸附探针分子（2,6-二甲基吡啶和一氧化碳）的红外光谱研究酸度，活性的起始与相对强的布朗斯特酸位点的形成相关。这些位点丰度的变化与催化活性相关。存在路易斯位点，但不能直接将其与活性联系起来。拉曼光谱、红外光谱和紫外光谱结果表明，活性位点与聚合物态钨表面物种有关。
