Controllable Synthesis of Single-Crystal Monolayer Graphene on Copper Foils by Low-Pressure Chemical Vapor Deposition

~50 μm single crystal graphene with hexagonal flower shape was synthesized on copper foils by low pressure chemical vapor deposition (LPCVD). The strong influence of Cu foils annealing on suppressing the nucleation of graphene was observed. Scanning electron microscopy (SEM), Optical microscopy (OM), and Raman spectrum showed that single crystal graphene as grown was monolayer with high quality. Suppressing nucleation through an annealing procedure offers an promising way to grow large-scale single crystal graphene controllably.