Dresden 2011 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
O: Fachverband Oberflächenphysik
O 67: Graphene IV
O 67.5: Talk
Thursday, March 17, 2011, 12:15–12:30, WIL B321
DFT and Photoemission Study of Water and Ammonia Adsorbed on Graphene/Ni(111) — •Stefan Böttcher1,2, Martin Weser1, Karsten Horn1, Yuriy Dedkov1, Elena Voloshina2, and Beate Paulus2 — 1Fritz-Haber Institut der Max-Planck Gesellschaft, Berlin, Germany — 2Freie Universität Berlin, Berlin, Germany
In order to use graphene in "real-world" application, the influence of ambient conditions has to be examined. We investigate the interaction of small molecules, H2O and NH3, with graphene/Ni(111) as model for ambient environment. We compare our results obtained with spectroscopical methods (ARPES and NEXAFS) and their comparison with DFT calculations. The live-PES measurements were performed in order to study the growth mode and the amount of adsorbed molecules. For NEXAFS and ARPES experiments we have prepared a reproducible amount of less than one molecular layer of water or ammonia on the graphene/Ni(111) interface. The inert properties of graphene/Ni(111) are confirmed, but we found a weak interaction of the physisorbed molecules with the graphene/Ni(111) system. The DFT calculations with GGA-PBE and PBE-D2 functionals were performed for several system geometries, which are based on the NEXAFS data. From the combination of ARPES and NEXAFS we can compare the experimentally and theoretically obtained electronic structures, to assign possible origins for the obtained interactions.