CO oxidation on cationic gold clusters: A theoretical study
- Authors: Prestianni, A; Martorana, A; Ciofini, I; Labat, F; Adamo, C
- Publication year: 2008
- Type: Articolo in rivista (Articolo in rivista)
- Key words: Engineering controlled terms: Adsorption; Carbon clusters; Carbon dioxide; Catalytic oxidation; Chemical oxygen demand; Chemical reactions; Flow interactions; Gold compounds; Oxidation Engineering uncontrolled terms: Catalytic sites; Cationic gold clusters; CO oxidations; Competitive interactions; Dioxygen; Elementary steps; Latter mechanisms; Molecular species; Neutral clusters; Oxidation of CO; Positively charged; Reaction paths; Supported golds Engineering main heading: Carbon monoxide
- OA Link: http://hdl.handle.net/10447/54066
Abstract
Aiming at understanding the elementary steps governing the oxidation of CO catalyzed by dispersed or supported gold nanoclusters, the reactivity of molecular species, such as O2 and CO, on neutral and positively charged Au13 clusters have been studied using a DFT approach. Two CO oxidation mechanisms have been simulated, involving respectively the adsorption of CO and O2 on adjacent catalytic sites (two-sites mechanism) and the competitive interaction of the reactants on the same site (single-site mechanism). It is demonstrated that in the former scheme a definite interaction of CO and O2 with both the charged and neutral cluster is effective, but that a chemical reaction between the adsorbates does not take place. Only the latter mechanism on positively charged Au13 cluster can give rise to the rupture of dioxygen and carbon dioxide formation. Detailed reaction paths corresponding to this case are calculated.