title: Controlling the Adsorption of Carbon Monoxide on Platinum Clusters by Dopant-Induced Electronic Structure Modification.
abstract: A major drawback of state-of-the-art proton exchange membrane fuel cells is the CO poisoning of platinum catalysts. It is known that CO poisoning is reduced if platinum alloys are used, but the underlying mechanism therefore is still under debate. We study the influence of dopant atoms on the CO adsorption on small platinum clusters using mass spectrometry experiments and density functional calculations. A significant reduction in the reactivity for Nb- and Mo-doped clusters is attributed to electron transfer from those highly coordinated dopants to the Pt atoms and the concomitant lower CO binding energies. On the other hand Sn and Ag dopants have a lower Pt coordination and have a limited effect on the CO adsorption. Analysis of the density of states demonstrates a correlation of dopant-induced changes in the electronic structure with the enhanced tolerance to CO poisoning.
authors.affiliation: Laboratory of Solid State Physics and Magnetism, KU Leuven, Celestijnenlaan 200d, Box 2414, 3001, Leuven, Belgium.
authors.forename: Piero
authors.initials: P
authors.lastname: Ferrari
authors.affiliation: Department of Theoretical, Atomic and Optical Physics, Universidad de Valladolid, Paseo Belén 7, 47011, Valladolid, Spain. lmolina@fta.uva.es.
authors.forename: Luis M
authors.identifier: 0000-0001-9559-2851
authors.initials: LM
authors.lastname: Molina
authors.affiliation: Laboratory of Solid State Physics and Magnetism, KU Leuven, Celestijnenlaan 200d, Box 2414, 3001, Leuven, Belgium.|Laboratory of Nanomaterials, Southern Federal University, 344090, Rostov-on-Don, Russia.
authors.forename: Vladimir E
authors.identifier: 0000-0003-0285-9815
authors.initials: VE
authors.lastname: Kaydashev
authors.affiliation: Department of Theoretical, Atomic and Optical Physics, Universidad de Valladolid, Paseo Belén 7, 47011, Valladolid, Spain.
authors.forename: Julio A
authors.identifier: 0000-0002-8604-8608
authors.initials: JA
authors.lastname: Alonso
authors.affiliation: Laboratory of Solid State Physics and Magnetism, KU Leuven, Celestijnenlaan 200d, Box 2414, 3001, Leuven, Belgium.
authors.forename: Peter
authors.identifier: 0000-0001-6570-0559
authors.initials: P
authors.lastname: Lievens
authors.affiliation: Laboratory of Solid State Physics and Magnetism, KU Leuven, Celestijnenlaan 200d, Box 2414, 3001, Leuven, Belgium. ewald.janssens@fys.kuleuven.be.
authors.forename: Ewald
authors.identifier: 0000-0002-5945-1194
authors.initials: E
authors.lastname: Janssens
keywords: carbon monoxide; clusters; density functional calculations; kinetics; mass spectrometry