AVS 52nd International Symposium
    Surface Science Thursday Sessions
       Session SS3-ThM

Paper SS3-ThM2
Pd-Au Model Catalysts: From Planar Surfaces to Nano-clusters

Thursday, November 3, 2005, 8:40 am, Room 203

Session: Reactivity of Bimetallic Surfaces
Presenter: K. Luo, Texas A&M University
Authors: K. Luo, Texas A&M University
C.-W. Yi, Texas A&M University
T. Wei, Texas A&M University
D.W. Goodman, Texas A&M University
Correspondent: Click to Email
Pd-Au bimetallic model catalysts were synthesized as planar surfaces and as well-dispersed alloy clusters on Mo(110) and SiO2 ultra-thin films, respectively, under ultrahigh vacuum (UHV) conditions. The surface composition, geometric and electronic structures, and CO adsorption properties have been characterized using ion scattering spectroscopy (ISS), X-ray photoelectron spectroscopy (XPS), infrared reflection absorption spectroscopy (IRAS), and temperature programmed desorption (TPD). Stable Pd-Au alloy surfaces, where the surface is significantly enriched in Au relative to the bulk, are obtained upon sequential deposition of Pd and Au followed by an anneal. Characteristic isolated Pd sites are identified on the Pd-Au planar and supported Pd-Au clusters. Ethylene absorption and dehydrogenation show a clear structure-activity correlation with respect to these Pd-Au model surfaces.