Berlin 2012 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
O: Fachverband Oberflächenphysik
O 53: Graphene IV
O 53.6: Talk
Wednesday, March 28, 2012, 18:00–18:15, MA 041
Nitrogen doped graphene on Ni(111) — •Roland J. Koch1, Martin Weser2, Markus Ostler1, Julian Gebhardt3, Francesc Vines3, Wei Zhao4, Christian Papp4, Andreas Görling3, Hans-Peter Steinrück4, Karsten Horn2, and Thomas Seyller1 — 1Lehrstuhl für Technische Physik, Universität Erlangen-Nürnberg, 91058 Erlangen — 2Fritz-Haber-Institut der Max-Planck-Gesellschaft, 14195 Berlin — 3Lehrstuhl für Theoretische Chemie, Universität Erlangen-Nürnberg, 91058 Erlangen — 4Lehrstuhl für Physikalische Chemie II, Universität Erlangen-Nürnberg, 91058 Erlangen
We report on the N doping of CVD-grown graphene on Ni(111) using a N-containing precursor. After in-situ growth, the graphene film was investigated using ARPES to study the valence band structure, and XPS was used to determine the N content and bonding situation. The results from PES were supplemented by DFT calculations for various slab models that mimic different possible doping situations. The valence band spectra show a broadening of the photoemission features as well as a shift of the bands with respect to the Fermi level. In order to decouple the N doped graphene film from the strongly interacting Ni substrate and to recover the Dirac cone, Au was intercalated. The XPS spectra show that the N doping is present in two different configurations. The majority of the N atoms are present in a pyridinic configuration, which involves a carbon vacancy. The minority of the N atoms is occupying a substitutional site. The observed variation of the electronic structure of N doped graphene compared to pristine graphene depends on the ratio of pyridinic to substitutional N.