Single Crystal Adsorption Microcalorimetry

9319234坎贝尔关于吸附过程的准确热力学信息对于从机理上理解表面反应至关重要。这些信息在很大程度上不能用于反应性分子物种在特征良好的固体表面上的吸附。这项研究项目得到了分析和表面化学计划的支持，旨在为许多催化重要的系统获得这类信息。这一信息将通过在超高真空条件下对特征良好的薄金属和金属氧化物单晶样品进行仔细的微量热测量来获得。这项工作将强调不能用更传统的方法(如热脱附谱)研究的体系。将获得有关吸附键强的详细信息，以及表面结构和组成对这些热力学性质的影响。%需要对吸附分子和催化表面之间的键合强度有基本的了解，才能开发和探索这些重要技术过程的反应机理。这项研究项目旨在开发和应用一种技术来直接测量这种吸附强度在性能良好的催化剂表面上。获得的热力学信息将对评估可能的表面反应机理和发展对催化重要过程的基本理解非常有用。***

9319234 Campbell Accurate thermodynamic information about adsorption processes is essential to developing a mechanistic understanding of surface reactions. This information is not available, for the most part, for adsorption of reactive molecular species on well characterized solid surfaces. This research project, supported in the Analytical and Suface Chemistry Program, is designed to obtain this sort of information for a number of catalytically important systems. This information will be obtained by careful microcalorimetry measurements on well characterized thin metal and metal oxide single crystal specimens under ultra high vacuum conditions. The work will emphasize systems which can not be studied by more traditional methods such as thermal desorption spectroscopy. Detailed information about adsorption bond strengths, and the effect of surface structure and composition on these thermodynamic properties will be obtained. %%% A basic understanding of the strength of bonding between an adsorbed molecule and a catalytic surface is needed in order to develop and probe reaction mechanisms for these technologically important processes. This research project is designed to develop and apply a technique for the direct measurement of this adsorption strength on well characterized catalytic surfaces. The thermodynamic information obtained will be very useful for evaluating possible surface reaction mechanisms and developing a basic understanding of catalytically important processes. ***