Adsorbate Photochemical Dynamics

这个研究项目，在分析和表面化学计划的支持下，解决了吸附在过渡金属表面上的分子光激发的详细动力学问题。 纳秒可调谐脉冲激光系统用于引发吸附在Pt（111）表面上的吸附物分子如甲烷、氮气和一氧化碳的光脱附、光碎裂和光反应。 角分辨飞行时间质谱用于检查解吸到气相中的物质，并且表面分析工具用于检查衬底的变化。 电子介导的光过程将通过使用碱吸附物来降低金属基底的功函数来检查。 在这项研究中获得的详细信息将有助于我们不断增长的理解多相催化和光辅助电子材料加工。 光与吸附分子的相互作用形成了分析和表面化学计划支持的该研究项目的主要焦点。 激光引发的过程，如解吸，碎裂和反应将通过检查过程的气相产物以及金属基材的变化来探测。 洞察到操作的非均相催化系统，以及有关激光辅助加工的电子材料的机械信息，应导致从这些研究。

This research project, supported in the Analytical and Surface Chemistry Program, addresses the question of the detailed dynamics of molecules photoexcited while adsorbed on transition metal surfaces. A nanosecond tunable pulsed laser system is used to initiate photodesorption, photofragmentation, and photoreaction of adsorbate molecules such as methane, nitrogen, and carbon monoxide adsorbed on the Pt(111) surface. Angle resolved time of flight mass spectrometry is used to examine species desorbing into the gas phase, and surface analytical tools are used to examine changes to the substrate. Electron mediated photoprocesses will be examined by the use of alkali adsorbates to lower the work function of the metallic substrate. Detailed information obtained in this research will be useful for our growing understanding of heterogeneous catalysis and photoassisted electronic materials processing. The interaction of light with adsorbed molecules forms the primary focus of this research project supported in the Analytical and Surface Chemistry Program. Laser initiated processes such as desorption, fragmentation, and reaction will be probed by examining the gas phase product of the process as well as changes to the metallic substrate. Insights into the operation of heterogeneous catalytic systems, as well as mechanistic information about laser assisted processing of electronic materials, should result from these studies.