The Spatial Dimension of Adsorption and Reaction of Metal Surfaces

这项研究项目在分析和表面化学计划的支持下，调查表面反应的空间维度。马里兰大学帕克分校的Reutt-Robey教授和她的同事利用扫描隧道显微镜和UHV光谱技术，研究了金属表面上的自扩散事件，以及这些事件与这些表面上的吸附和反应过程的相互作用。利用氢在Al(111)邻近表面上的吸附研究了台阶表面的位置分布以及吸附驱动的台阶运动和刻蚀。为了解决反应物的有序性和反应几率的空间相关性问题，监测了吸附在Ag(001)面上的碘苯和丙基碘的碳-碳偶联反应。在表面反应的空间依赖性研究中，Reutt-Robey教授正在研究多相催化的分子机制。使用微观和光谱方法解决这些问题，她能够阐明由反应物吸附引起的催化剂台阶运动的详细机制，以及反应物取向对特定反应发生的可能性的影响。从这些研究中获得的信息有助于详细了解多相催化这一具有重要技术意义的领域。

This research project, supported by the Analytical and Surface Chemistry Program, investigates the spatial dimension of surface reactions. Using scanning tunneling microscopy and UHV spectroscopic techniques, Professor Reutt-Robey and her coworkers at the University of Maryland-College Park are exploring self-diffusion events on metallic surfaces and the interaction of these events with adsorption and reaction processes on these surfaces. Hydrogen adsorption on vicinal Al(111) surfaces is used to probe stepped surface site distributions and adsorption driven step motion and facetting. Carbon-carbon coupling reactions of adsorbed iodobenzene and propyliodide are monitored on the Ag(001) surface in order to address the questions of reactant ordering and spatial dependences of reaction probabilities. In studies of the spatial dependence of surface reactions, Professor Reutt-Robey is addressing the molecular mechanisms of heterogeneous catalysis. Using microscopic and spectroscopic approaches to these questions, she is able to elucidate the detailed mechanisms of catalyst step motion induced by reactant adsorption, and the effect of reactant orientation on the likelihood of a particular reaction occurring. The information gained from these studies is useful in developing a detailed understanding of the technologically important field of heterogeneous catalysis.