Density Functional Theoretical Study of Graphene on Transition-Metal Surfaces: The Role of Metal d-Band in the Potential-Energy Surface

The nature of graphene/substrate interfaces needs to be understood to improve the crystalline quality of graphene films grown with chemical vapor deposition (CVD). We have theoretically investigated the potential energy surface (PES) of graphene on catalyst transition-metal surfaces. The profile of PES highly depends on the type of underlying metals; the orders of the peak-to-valley (PV) values of PES are Cu < Ni < Co (3d), Pd < Rh < Ru (4d), and Pt < Ir < Os (5d). High PV values were found to be provided by metals with d-band close to the Dirac point of graphene. Our results indicate that the d-band of catalyst metals greatly influences the PES profile of graphene on the metals, which should be helpful for further understanding of the graphene/metal interfaces and its behavior in CVD growth process.