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4092065 
Journal Article 
Hydrogen activation on silver: A computational study on surface and subsurface oxygen species 
Mohammad, AB; Yudanov, IV; Lim, KokHwa; Neyman, KM; Roesch, N 
2008 
Yes 
Journal of Physical Chemistry C
ISSN: 1932-7447
EISSN: 1932-7455 
112 
5 
1628-1635 
WOS:000252814800048 
Clean silver is known to be inert toward H-2 dissociation. Nevertheless, silver catalysts recently have been found to exhibit a noteworthy selectivity in the hydrogenation of unsaturated aldehydes to unsaturated alcohols. Experimental studies indicate that pretreatment in oxygen atmosphere activates the catalyst. To examine the role of oxygen in activation of hydrogenation catalysts, we carried out a density functional study on periodic slab models of H-2 dissociation at various oxygen species on silver surfaces, including subsurface oxygen. According to our calculations all oxygen forms under scrutiny promote dissociation of molecular hydrogen. With hydrogenation reactions in mind, we discuss a mechanism according to which an oxygen species, before it desorbs as a water molecule, produces one or two active hydrogen atoms on a metal terrace.