Model Nanocluster Catalysts: The Role of Size, Shape and Composition on the Catalytic Activity of Monometallic, Bimetallic and Metal Oxide Clusters on Oxide Surfaces

在这项由分析和表面化学计划支持的研究中，Buratto，Bowers和Metiu教授及其团队将制备，表征和测试三种新型纳米催化剂，它们具有一个共同特征：非常小，孤立，定义明确的催化活性位点。 他们将准备和研究（a）非常小的Aun和Agn质量选择的簇支持在氧化物上，（B）非常小的质量选择，二元簇，如PdmAun支持在氧化物上，和（c）非常小的，质量选择的氧化物簇支持在氧化物上。 将以协调一致的方式使用各种技术来研究这些重要的催化过程：将通过在氧化物表面沉积质量选择的簇来制备模型催化系统，以确保逐个原子控制催化剂的大小;将通过表面科学技术在超高真空中制备和研究所有样品（AES、XPS）以及STM/ AFM在催化化学之前、期间和之后;并且密度泛函理论（DFT）将用于计算簇的结构、它们的XPS谱和它们的化学活性。通过这里提出的工作，他们将详细了解这些材料的催化化学，并找出这种化学如何取决于尺寸，成分和基材的性质。 虽然研究的重点是特定纳米催化剂的催化活性，但研究结果很有可能适用于其他系统。 此外，希望通过这项研究开发的概念将有助于优化使用这些纳米级催化剂的重要工业过程，并为发现新的纳米级催化材料提供见解。 研究生将与三个不同的研究小组不断互动，将与其他杰出的科学家进行日常接触，并将获得大量表面科学，气相化学，扫描探针显微镜和高级理论技术的实践经验。 这项研究将为研究生教育提供宝贵的机会，在世界上很少有地方发现。 由该补助金（包括PI）支持的研究人员也将积极推广到圣巴巴拉地区的K-12学校，以提供关于多相催化的原子论观点的教程，并展示我们模型催化剂系统的原子分辨率图片。 这将包括在UCSB化学系目前活跃的外展计划中。 一系列关于纳米结构催化的讲座将被开发并作为目前材料化学课程中教授的纳米科学课程的一部分。

In this research supported by the Analytical and Surface Chemistry Program, Professors Buratto, Bowers, and Metiu and their groups will prepare, characterize, and test three new types of nanoscale catalysts, having one feature in common: very small, isolated, well-defined, catalytically active sites. They will prepare and study (a) very small Aun and Agn mass-selected clusters supported on oxide, (b) very small mass-selected, binary clusters such as PdmAun supported on oxides, and (c) very small, mass-selected oxide clusters supported on oxides. A variety of techniques will be used, in a concerted manner, to study these important catalytic processes: model catalytic systems will be prepared by depositing mass-selected clusters on oxide surfaces to ensure atom-by-atom control of catalyst size; all samples will be prepared and studied in ultra-high vacuum by surface science techniques (AES, XPS) as well as by STM/ AFM before, during and after the catalytic chemistry; and density functional theory (DFT) will be used to calculate the structure of the clusters, their XPS spectrum and their chemical activity. Through the work proposed here they will develop a detailed understanding of the catalytic chemistry of these materials and find out how this chemistry depends on size, composition and the nature of the substrate. While the focus of the research is on the catalytic activity of specific nanoscale catalysts, there is a high probability that the results will be applicable to other systems. In addition, it is hoped that the concepts developed through this research will help optimize important industrial processes using these nanoscale catalysts and provide insight into the discovery of new nanoscale catalytic materials.The research funded by this grant will be interdisciplinary. Graduate students will interact continuously with three different research groups, will have daily contact with other outstanding scientists, and will acquire hands-on experience in a large number of techniques of surface science, gas-phase chemistry, scanned probe microscopy, and high level theory. The research will provide a valuable opportunity for graduate education, found in very few places in the world. Researchers supported by this grant (including PIs) will also be active in outreach to K-12 schools in the Santa Barbara area to present a tutorial on an atomistic view of heterogeneous catalysis and to show an atomically-resolved picture of our model catalyst systems. This will be included in the currently active outreach program in the chemistry department at UCSB. A series of lectures on catalysis by nanostructures will be developed and included as part of a course in nanoscience currently taught in the materials chemistry curriculum.