Atomic level studies of structure and reactivity of bimetallic surfaces are carried out in this research project supported by the Analytical and Surface Chemistry Program and the Office of Multidisciplinary Activities. Professor Koel and his coworkers at the University of Southern California have developed ultra high vacuum scanning tunneling microscope instrumentation which allows the identification of adsorption sites and molecular adsorbates on metallic surfaces. Correlations between reactivity of model bimetallic surfaces and the atomic level structure and occupation of step and defect sites on these surfaces will be made. Pt-Sn alloy surfaces, and Pd thin films on refractory metal substrates are being examined, and various hydrocarbon reactions on these surfaces, including acetylene trimerization to form benzene, are being probed. Insights gained from these studies will be valuable in developing our understanding of important catalytic processes. Correlations between atomic level structure of bimetallic surfaces and the reaction chemistry of these surfaces are being made in this research project. Hydrocarbon reactions relevant to heterogeneous catalysis are examined on well characterized Pt-Sn and Pd-Mo substrates, in order to probe the effect of metal atom ensembles and defect sites on these surfaces. Atomic level characterization using scanning probe microscopy forms the basis of these studies which will provide insight into the operation of important catalytic systems.
