Model Supported Metal Catalysts

结构简单、高度分散的负载型金属催化剂 制备并表征。 该催化剂由以下物质制备： 将有机金属前体转化为 在表面上具有确定结构的有机金属簇 碱性载体（氧化镁和氧化镧）;随后 脱羰得到负载的金属原子簇， 与前体相同数量的原子。 这里面使用的金属 铱和铂。 样品的特征在于 红外光谱，扩展X射线吸收精细结构 （EXAFS）和透射电子显微镜;催化 测量烃类的活性和选择性 转化反应 这是一个基本的研究分散的影响， 上限（或者说，集群大小的影响 在小簇中）对金属的催化性能的影响。 的 问题是系统优化的关键问题 将稀有金属催化剂用于各种工业能源， 和环境目的。

Structurally simple, highly dispersed, supported metal catalysts are prepared and characterized. The catalysts are prepared from organometallic precursors which are converted into organometallic clusters of defined structures on the surfaces of basic supports (magnesia and lanthana); subsequent decarbonylation gives clusters of supported metal atoms with the same number of atoms as the precursors. The metals used in this study are iridium and platinum. Samples are characterized with infrared spectroscopy, extended X-ray adsorption fine structure (EXAFS), and transmission electron microscopy; catalytic activities and selectives are measured for hydrocarbon conversion reactions. This is a fundamental study of the effects of dispersion near the upper limit (or, equivalently, the effects of cluster size in small clusters) on the catalytic properties of metals. The issue is a critical one for the optimization of systems employing rare-metal catalysts for a variety of industry energy and environmental purposes.