02314nas a2200241   4500008004100000022001400041245011900055210006900174260008900243300001200332490000800344520137100352653002601723653002801749653001901777653001401796653001201810653002501822100003201847700003201879700003001911856013101941       2009                        eng d  a0169-433200aElectronic decoupling of surface layers from bulk and its influence in oxidation catalysis: a molecular beam study0 aElectronic decoupling of surface layers from bulk and its influe  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbInst Phys; Indian Assoc Cutivat ScicOCT  a443-4480 v2563 a<p>Interactions between oxygen and Pd-surfaces have important implications, especially towards oxidation reactions, and influence of subsurface oxygen to oxidation reactions is the focus of the present study. In our efforts to understand the above aspects, CO oxidation reactions have been carried out with mixed molecular beam (MB), consisting CO and O(2), on Pd(1 1 1) surfaces under a wide variety of conditions (T = 400-900 K, CO: O(2) = 7: 1 to 1: 10). A new aspect of the above reaction observed in the transient kinetics regime is the evidence for oxygen diffusion into Pd subsurface layers, and its significant influence towards CO oxidation at high temperatures (&gt;= 600 K). Interesting information derived from the above studies is the necessity to fill up the subsurface layers with oxygen atoms to a threshold coverage (theta(O-sub)), above which the reactive CO adsorption occurs on the surface and simultaneous CO(2) production begins. There is also a significant time delay (G) observed between the onset of oxygen adsorption and CO adsorption (and CO(2) production). Above studies suggest an electronic decoupling of oxygen covered surface and subsurface layers, which is slightly oxidized, from the metallic bulk, which induces CO adsorption at high temperatures and simultaneous oxidation to CO(2). (C) 2009 Elsevier B.V. All rights reserved.</p>10aElectronic decoupling10aheterogeneous catalysis10amolecular beam10aOxidation10aPd(111)10aSubsurface diffusion1 aThirunavukkarasu, Kandasamy1 aNagarajan, Sankaranarayanan1 aGopinath, Chinnakonda, S.  uhttps://library.ncl.res.in/content/electronic-decoupling-surface-layers-bulk-and-its-influence-oxidation-catalysis-molecular-0