Adsorption Energetics on Well-Defined Surfaces by Microcalorimetry

在分析和表面化学计划的支持下，华盛顿大学的坎贝尔教授和他的同事们正在直接测量小分子在特征良好的单晶金属表面上的吸附热。利用在NSF支持下开发的独特微量热计方法，该小组正在研究与催化、微电子制造、化学传感和纳米技术相关的表面化学反应中几个关键吸附中间体的形成热。特别是，正在测定几个吸附在fcc(111)表面的中间物种的生成热，包括CH3、CH2、烯丙基、羟基和甲氧基。还研究了金属在半导体表面如Si(100)上的吸附和附着能。这些基本信息对微电子加工和多相催化体系的设计是有用的。坎贝尔教授和他的同事们正在使用灵敏的微量热方法测量过渡金属表面上重要催化中间体形成的热力学。对表征良好的表面反应热的准确测量为催化工艺的设计和微电子制造方法提供了基本的理解。学生们正在接受作为这些重要技术领域基础的基础科学培训。

AbstractCHE-0502177Campbell/WashingtonWith the support of the Analytical and Surface Chemistry Program, Professor Campbell and his coworkers at the University of Washington are directly measuring the enthalpies of adsorption of small molecules on well characterized single crystal metal surfaces. Using unique microcalorimetry methods developed with NSF support, this group is examining the enthalpies of formation of several key adsorbed intermediates in surface chemical reactions of relevance to catalysis, microelectronics fabrication, chemical sensing and nanotechnology. In particular, heats of formation are being determined for several adsorbed intermediate species on fcc(111) surfaces, including CH3, CH2, allyl, hydroxyl, and methoxy. Adsorption and adhesion energies of metals on semiconductor surfaces such as Si(100) are also being examined. This fundamental information is useful for the design of microelectronics processing and heterogeneous catalytic systems. Using sensitive microcalorimetric methods, Professor Campbell and his colleagues are measuring the thermodynamics of formation of important catalytic intermediates on transition metal surfaces. Accurate measurements of the heats of reaction on well characterized surfaces provide fundamental understanding for the design of catalytic processes, and microelectronics manufacturing approaches. Students are being trained in the basic science that underlies these important technological areas.