Common surface structures of graphene and Au(111): The effect of rotational angle on adsorption and electronic properties.

Graphene adsorption on the Au(111) surface was explored to identify its common surface structures by means of van der Waals corrected density functional theory calculations. The alignment of graphene in the form of certain rotational angles on the gold surface has an important role in lattice matching, which causes Moiré patterns, and in the electronic properties of the resulting common cell structures. Dispersive weak interactions between carbon and gold layers lead to a downward shift of Fermi energy of the adsorption system with respect to the Dirac point of graphene showing a p-type doping character. Moreover, the shift was shown to depend on the rotational angle of graphene on Au(111).