Synthesis of graphene through the carbidization of Gd on pyrolytic graphite

The formation of graphene on the surface of a Gd film on a highly oriented pyrolytic graphite substrate has been studied by photoelectron spectroscopy using synchrotron radiation. It has been demonstrated that the formation of graphene passes through the phase of gadolinium carbidization, which is transformed with increasing annealing temperature. It has been established that, at a temperature of 1300 K, gadolinium carbide with the Gd$_2$C$_3$ stoichiometry is transformed into the carbide with the GdC$_2$ stoichiometry. The analysis of all transient phase processes has been performed on the basis of the fine structure of photoelectron lines and dispersion of electron states. It has been shown that the Dirac cone of electron states of graphene is retained.