Unravelling the origin of the high-catalytic activity of supported Au: a density-functional theory-based interpretation.
Using first principles DF calculations we have studied the structural and catalytic properties of Au supported on TiOx-Mo(112) films. Our theoretical models are consistent with an initial (8 x 2) Mo(112)-Ti2O3 pattern which after Au deposition gives rise to ordered Au films that completely wet the surface. The oxidation of CO on model surfaces at coverage 1, 4/3, and 5/2 ML has been analyzed. The oxidation proceeds through a peroxo-like complex in which molecular oxygen is simultaneously bound to the CO and the surface. The energy barrier computed for a Au coverage of 4/3 ML is found significantly lower in agreement with the unusual high activity observed for this catalyst. The detailed analysis of the geometry and electronic structure provides a fundamental understanding of the reaction.
Hernandez
Norge Cruz
NC
Departamento de Química Física, Facultad de Química, Universidad de Sevilla, E-41012 Sevilla, Spain.
Sanz
Javier Fdez
JF
Rodriguez
José A
JA