title: Reversible hydrogenation of graphene on ni(111)-synthesis of "graphone".
abstract: Understanding the adsorption and reaction between hydrogen and graphene is of fundamental importance for developing graphene-based concepts for hydrogen storage and for the chemical functionalization of graphene by hydrogenation. Recently, theoretical studies of single-sided hydrogenated graphene, so called graphone, predicted it to be a promising semiconductor for applications in graphene-based electronics. Here, we report on the synthesis of graphone bound to a Ni(111) surface. We investigate the formation process by X-ray photoelectron spectroscopy (XPS), temperature-programmed desorption (TPD), and density-functional theory calculations, showing that the hydrogenation of graphene with atomic hydrogen indeed leads to graphone, that is, a hydrogen coverage of 1 ML (4.2 wt %). The dehydrogenation of graphone reveals complex desorption processes that are attributed to coverage-dependent changes in the activation energies for the associative desorption of hydrogen as molecular H2 .
authors: Lehrstuhl für Physikalische Chemie II, Universität Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen (Germany).
authors: Wei
authors: W
authors: Zhao
authors: Julian
authors: J
authors: Gebhardt
authors: Florian
authors: F
authors: Späth
authors: Karin
authors: K
authors: Gotterbarm
authors: Christoph
authors: C
authors: Gleichweit
authors: Hans-Peter
authors: HP
authors: Steinrück
authors: Andreas
authors: A
authors: Görling
authors: Christian
authors: C
authors: Papp
keywords: X-ray photoelectron spectroscopy; dehydrogenation; density functional calculations; graphene; graphone; hydrogenation