Chemistry Department Seminar

Achieving higher activity and selectivity of heterogeneous catalysts, electrocatalysts, and sensors requires advances in controlling structure and chemistry relevant to interfacial reactions at the nanoscale. One can now exploit an unprecendented ability to investigate such phenomena on ally surfaces to obtain new information about how and why composition, structure, and defects alter chemical reactions that occur at specific sites. We have been probing this "site-directed" chemistry at alloy surfaces in a wide range of chemisorption and catalytic reactivity studies. The talk will focus on how recent results for several Sn/Pt(111) and Sn/Pt(100) ordered surface alloys have helped to define the overall chemical reactivity of Pt-Sn bimetallic surfaces, clarified the role of a second metal in altering the chemistry of Pt alloys, and led to general principles for understanding the reactivity and selectivity of alloy catalysts. In addition, we have determined how to control formation of specific metal oxide nanostructures via oxidation of these alloys or by vapor deposition. Fundmental concepts emerging from all of these studies enhance our understanding and ability to tailor local properties of alloy and oxide surfaces, which should facilitate the design of new catalysts and sensors.