title: Hydrogen-graphite interaction: Experimental evidences of an adsorption barrier.
abstract: The interaction of H atoms having relatively low average kinetic energy (∼0.025 eV) with both perfectly clean and D-covered HOPG surfaces is investigated using high resolution electron energy loss spectroscopy. From this study we confirm, in a controlled fashion, the presence of the theoretically predicted adsorption barrier since no adsorption is detected for such H atoms on HOPG. Moreover, we demonstrate that the exposure of a D saturated HOPG surface to these H atoms results in the complete removal of adatoms, with no further adsorption despite the prediction of the adsorption barrier to vanish for H dimers in para configuration. Therefore, the recombinative abstraction mechanism which competes with the adsorption process is more efficient.
authors.affiliation: Laboratoire de Physique des Interactions Ioniques et Moléculaires, UMR 6633 CNRS-Université de Provence, Centre de Saint-Jéro^me, Case 241, Avenue de l'Escadrille Normandie-Niemen, 13397 Marseille Cedex 20, France. etienne.areou@etu.univ-provence.fr
authors.forename: E
authors.initials: E
authors.lastname: Aréou
authors.forename: G
authors.initials: G
authors.lastname: Cartry
authors.forename: J-M
authors.initials: JM
authors.lastname: Layet
authors.forename: T
authors.initials: T
authors.lastname: Angot
mesh_terms: D000327:Adsorption; D006108:Graphite / Q000737:chemistry*; D006859:Hydrogen / Q000737:chemistry*; D007700:Kinetics; D013499:Surface Properties
chemical_list: D006108:Graphite; D006859:Hydrogen