We report the synthesis of high quality few-layer graphene on a large scale using high purity natural graphite from Sri Lanka. A novel thermal method was adapted to prepare graphene from intermediate graphite oxide, w...We report the synthesis of high quality few-layer graphene on a large scale using high purity natural graphite from Sri Lanka. A novel thermal method was adapted to prepare graphene from intermediate graphite oxide, which was obtained by heating the intermediate at low temperature （above 150 ℃） in air for 5 min and subsequent heating at 500℃ in Argon for 15 min. The samples were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, Raman spec- troscopy etc. The properties and the performance of graphene were observed to depend on the graphite source. The reduced graphite oxide from Kahatagaha graphite source exhibits higher Brunauer-Emmett- Teller specific surface area -500 m^2 g^-1 and stable specific capacity as an anode in Li-ion batteries, whereas Bogala graphite showed higher initial irreversibility and higher capacity as anode, exceeding the theo- retical specific capacity of graphite. Both graphenes showed high electrical conductivity. The graphene, which exists in stacks of only a few layers, supposed to be 2-6 layers, would be promising for a vast variety of applications.展开更多
基金provided by the Australian Research Council (ARC) Discovery Project (DP 0987805)NRC (12-022)/Treasury Grants (ITI) Sri Lanka
文摘We report the synthesis of high quality few-layer graphene on a large scale using high purity natural graphite from Sri Lanka. A novel thermal method was adapted to prepare graphene from intermediate graphite oxide, which was obtained by heating the intermediate at low temperature （above 150 ℃） in air for 5 min and subsequent heating at 500℃ in Argon for 15 min. The samples were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, Raman spec- troscopy etc. The properties and the performance of graphene were observed to depend on the graphite source. The reduced graphite oxide from Kahatagaha graphite source exhibits higher Brunauer-Emmett- Teller specific surface area -500 m^2 g^-1 and stable specific capacity as an anode in Li-ion batteries, whereas Bogala graphite showed higher initial irreversibility and higher capacity as anode, exceeding the theo- retical specific capacity of graphite. Both graphenes showed high electrical conductivity. The graphene, which exists in stacks of only a few layers, supposed to be 2-6 layers, would be promising for a vast variety of applications.
