Chemisorption and reactions studies on well-characterized bimetallic and alloy surfaces. Final report.

摘要

The authors have investigated the following major areas important to understanding bimetallic and alloy surface chemistry and catalysis: (1) the influence of potassium on the interactions of ethylene and other hydrocarbon species with platinum, (2) the determination of ensemble size requirements for adsorption and reaction on platinum surfaces, (3) the influence of oxygen adatoms on the bonding of nitric oxide to platinum, and (4) the role of the electronic structure of the metal surface in controlling surface chemistry. All of these studies were carried out using surface science techniques on well-characterized metal surfaces. A major effort and a major achievement of work have been to study model systems designed to explain how changes in geometric and electronic structure of metal surfaces affect surface chemistry. Specifically, the influence of potassium and bismuth coadsorption with small molecules on a Pt(111) single crystal surface can be compared to separate electronic effects from those of ensemble size effects. We also report the first measurements of the heat of adsorption of carbon monoxide as a function of Pd film thickness for thin films which have dramatically altered geometric and electronic structure.