First-principles study of the interaction and charge transfer between graphene and metals

Measuring the transport of electrons through a graphene sheet necessarily involves contacting it with metal electrodes. We study the adsorption of graphene on metal substrates using first-principles calculations at the level of density-functional theory. The bonding of graphene to Al, Ag, Cu, Au, and Pt (111) surfaces is so weak that its unique ``ultrarelativistic'' electronic structure is preserved. The interaction does, however, lead to a charge transfer that shifts the Fermi level by up to 0.5 eV with respect to the conical points. The crossover from $p$-type to $n$-type doping occurs for a metal with a work function $\ensuremath{\sim}5.4\text{ }\text{eV}$, a value much larger than the work function of…

• SV
  Stichting voor Fundamenteel Onderzoek der Materie
• NO
  Nederlandse Organisatie voor Wetenschappelijk Onderzoek