Superconductivity in metal-coated graphene

In this work we explore, by first-principles density functional theory (DFT) calculations, the possibility of inducing electronphonon mediated superconductivity in a graphene sheet by doping its surface with alkaline metal adatoms. We demonstrate that, contrary to what could be naively believed, simple exfoliation to one layer of superconducting graphite intercalated compounds (GICs) does not necessarily lead to superconducting graphene, as it is the case in CaC6. On the contrary, it is meaningful to look for superconductivity in monolayers obtained by exfoliating non-superconducting GICs. In particular, we demonstrate that Li coating and double-coating of graphene leads to superconductivity in graphene with T-c that could be as large as 18 K. (C) 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim