Preparation And Defects Of Graphene Research,

Due to the magnificent physical properties and potential applications, Graphene stir up a great wave in the community. Graphene is a two-dimension material with zero gaps, whose carbon atoms make up two-dimension cellular structure by SP2 orbitalhybridization. Graphene possesses good thermal conductivity, high strength and extra large specific surface area, which lead the wide application prospects in energy storage, electron device, composite materials and sensors.In this work, graphene were prepared by oxidoreduction process, and the mechanism of nucleation was investigated. Beside, the effect of monovacancy defect, bivacancy defect and Stone-Wales defect on the electronic structure of graphene, and the effect of Fe-doping on the electricity and magnetic properties of graphene were calculated by first-principles methods based DFT (Density Functional Theory). The main work and conclusions are following:(1) Graphene were successfully fabricated by oxidoreduction process. Owing to the limitation of prepare process, as-prepared graphene have some defects, including monovacancy defect, bivacancy defect and Stone-Wales defect.(2) Monovacancy defect, bivacancy defect and Stone-Wales defect can affect the electronic structure of graphene, and have different influence on the gap of graphene. The gaps of graphene with monovacancy defect, bivacancy defect and Stone-Wales defect are 1.591 eV,1.207eV and 0.637eV, respectively.(3) Intrinsic graphene is a material with zero gap and nonmagnetic. Fe-doping can change both the gap and the magnetic properties of graphene. Fe-doped graphene owns the gap of 1.51 eV and existence of magnetism.