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1. Science, 311 (2006), 362-365, “Solvent-Free Oxidation of Primary Alcohols to Aldehydes Using Au-Pd/ TiO2 Catalysts”, Enache#, Edwards#, Landon#, Solsona-Espriu#, Carley#, Herzing*, Watanabe*, Kiely*, Knight# & Hutchings# #School of Chemistry, Cardiff University MET DMR-0304738 *Center for Advanced Materials and Nanotechnology, Lehigh University TiO2-supported Au-Pd alloy catalysts The TiO2-supported Au-Pd alloy nanoparticles are the active component of a new environmentally friendly catalyst that efficiently promotes the oxidation of primary alcohols to aldehydes under mild solvent-free conditions. Fig. 1 shows comparison of the TiO2/Au-Pd alloy catalysts (triangles) with TiO2/Au (squares) and TiO2/Pd (circles) monometallic catalysts in terms of the oxidation of benzyl alcohol at 373 K. Although the benzaldehyde selectivity (open symbols) is decreased with an increase of Au addition to Pd, the Au-Pd catalysts remain high selectivity at high conversion rates (closed symbols). The catalytic performance is improved by alloying of Au to Pd. Characterization of TiO2-supported Au-Pd alloy catalysts Fig.2 shows an annular dark-field image and X-ray maps of Au and Pd obtained from a TiO2 -supported Au-Pd nanoparticle. To enhance weak X-ray signals, multivariate statistical analysis, which was developed under our NSF support DMR-0304738, was applied. The Pd signal originates from a slightly larger area than that of the Au map as clearly illustrated in the color overlay (red: Ti, green: Pd and blue: Au). Hence, Pd is segregated on the particle surface during calcination. It can be concluded that Au acts as an electronic promoter for Pd and the active catalyst has a surface that is significantly enriched in Pd. closed symbols open symbols Fig.2 Fig.1