OXIDATION OF CARBON-MONOXIDE AND ETHYLENE ON PD(001)-C(2X2)MN

Oxidation of carbon monoxide and ethylene on an in situ prepared order ed Pd(001)-C(2x2)Mn alloy surface was investigated by LEED and HREELS. At 140 K, coadsorption of carbon monoxide and oxygen gives anew HREEL S feature at 2300 cm(-1) which is tentatively assigned to the formatio n of adsorbed carbon dioxide with the molecular axis nearly perpendicu lar to the alloy surface. Meanwhile, ethylene reacts with oxygen on th e ordered alloy surface at temperatures higher than 230 K to produce s urface hydroxyl species and adsorbed CO. Bimetallic composition and th e buckled structure of the alloy surface are responsible for the high reactivity and the stabilization of reaction intermediates in the two oxidation processes.