▎ 摘 要
Graphene-metal interfaces have recently become popular for graphene growth and for making contacts in numerous thermal and photo-electronic devices. A number of studies have already been made to investigate the interfacial properties when single layer graphene is grown on metal substrates. In this study, we consider the physisorption of bilayer graphene on metals and find a significant bandgap opening which is otherwise absent in the single layer case. This gap arises from the asymmetry in the bilayer due to the charge transfer process at the interface. This charge transfer also causes doping in the bilayer graphene and a corresponding shift in the Fermi level. In this work, we present a thorough investigation into the induced bandgap and Fermi level shift when bilayer graphene is adsorbed on Cu, Al, Ag, Pt, and Au(111) surfaces first by reporting their values from Density Functional Theory (DFT) studies with Local Density Approximation functional used for exchange-correlation energy. Next, to obtain an enhanced picture of the surface physics at play (which is usually obscured by the complexities of DFT), we provide an analytical model to relate the induced bandgap and Fermi level shift to the metal work function and interface separation distance. The values predicted from the model shows a high degree of correlation with the values obtained from the DFT simulation. The results are expected to greatly facilitate the understanding of bilayer graphene adsorption on metals, which in turn may aid the study of graphene electronic devices. Published by AIP Publishing.