Graphene have been promising as an alternative to silicon in electronic industrial application since the experimental discovery and characterization of monolayer graphite in 2004.As a novel organic electronic material,the molecular structures and their electronic properties depend on carbon atomic array through covalent binding,precision of length and width of single layer.Generally,the critical requirements for large-scale production of ideal graphene are (1) precision of molecular structures of graphene,(2) high yield of single layer,(3) accessibility of processing and (4) ease of functionalization.Current popular preparation of graphene includes exfoliation of graphite,reduction of graphene oxide and epitaxial growth of graphene film on copper foils.