By a News Reporter-Staff News Editor at Journal of Engineering -- Data detailed on Ultramicroscopy have been presented. According to news reporting from Oxford, United Kingdom, by VerticalNews journalists, research stated, "A major practical challenge in heterogeneous catalysis is to minimize the loading of expensive platinum group metals (PGMs) without degrading the overall catalytic efficiency. Gaining a thorough atomic-scale understanding of the chemical/structural changes occurring during catalyst manufacture/operation could potentially enable the design and production of 'nano-engineered' catalysts, optimized for cost, stability and performance."
The news correspondents obtained a quote from the research from the University of Oxford, "In the present study, the oxidation behavior of a Pt-31 at% Pd alloy between 673-1073 K is investigated using atom probe tomography (APT). Over this range of temperatures, three markedly different chemical structures are observed near the surface of the alloy. At 673 K, the surface oxide formed is enriched with Pd, the concentration of which rises further following oxidation at 773 K. During oxidation at 873 K, a thick, stable oxide layer is formed on the surface with a stoichiometry of PdO, beneath which a Pd-depleted (Pt-rich) layer exists. Above 873 K, the surface composition switches to enrichment in Pt, with the Pt content increasing further with increasing oxidation temperature. This treatment suggests a route for tuning the surfaces of Pt-Pd nanoparticles to be either Pd-rich or Pt-rich, simply by adjusting the oxidation temperatures in order to form two different types of core-shell structures."
According to the news reporters, the research concluded: "In addition, comparison of the oxidation behavior of Pt Pd with Pt Rh and Pd Rh alloys demonstrates markedly different trends under the same conditions for these three binary alloys."
For more information on this research see: Atomic engineering of platinum alloy surfaces. Ultramicroscopy, 2013;132():205-211. Ultramicroscopy can be contacted at: Elsevier Science Bv, PO Box 211, 1000 Ae Amsterdam, Netherlands.
Our news journalists report that additional information may be obtained by contacting T. Li, University of Oxford, Dept. of Chem, Wolfson Catalysis Center, Oxford OX1 3QR, United Kingdom. Additional authors for this research include P.A.J. Bagot, E.A. Marquis, S.C.E. Tsang and G.D.W. Smith.
Keywords for this news article include: Oxford, Europe, Engineering, United Kingdom, Ultramicroscopy
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