Catalysis Applications of Size-Selected Cluster Deposition

详细信息    查看全文

• 作者：Stefan Vajda ; Michael G. White
• 刊名：ACS Catalysis
• 出版年：2015
• 出版时间：December 4, 2015
• 年：2015
• 卷：5
• 期：12
• 页码：7152-7176
• 全文大小：1714K
• ISSN：2155-5435

文摘

In this Perspective, we review recent studies of size-selected cluster deposition for catalysis applications performed at the U.S. DOE National Laboratories, with emphasis on work at Argonne National Laboratory (ANL) and Brookhaven National Laboratory (BNL). The focus is on the preparation of model supported catalysts in which the number of atoms in the deposited clusters is precisely controlled using a combination of gas-phase cluster ion sources, mass spectrometry, and soft-landing techniques. This approach is particularly effective for investigations of small nanoclusters, 0.5鈥? nm (<200 atoms), where the rapid evolution of the atomic and electronic structure makes it essential to have precise control over cluster size. Cluster deposition allows for independent control of cluster size, coverage, and stoichiometry (e.g., the metal-to-oxygen ratio in an oxide cluster) and can be used to deposit on any substrate without constraints of nucleation and growth. Examples are presented for metal, metal oxide, and metal sulfide cluster deposition on a variety of supports (metals, oxides, carbon/diamond) where the reactivity, cluster鈥搒upport electronic interactions, and cluster stability and morphology are investigated. Both UHV and in situ/operando studies are presented that also make use of surface-sensitive X-ray characterization tools from synchrotron radiation facilities. Novel applications of cluster deposition to electrochemistry and batteries are also presented. This review also highlights the application of modern ab initio electronic structure calculations (density functional theory), which can essentially model the exact experimental system used in the laboratory (i.e., cluster and support) to provide insight on atomic and electronic structure, reaction energetics, and mechanisms. As amply demonstrated in this review, the powerful combination of atomically precise cluster deposition and theory is able to address fundamental aspects of size-effects, cluster鈥搒upport interactions, and reaction mechanisms of cluster materials that are central to how catalysts function. The insight gained from such studies can be used to further the development of novel nanostructured catalysts with high activity and selectivity.