School of Physics Science and Engineering,Zhongshan University, Guangzhou 510275,China; 2.Guangzhou Institute of Chemistry,Chinese Academy of Sciences, Guangzhou 510650,China; 3.School of Material Science and Engineering,South China University of Technology, Guangzhou 510641,China
Graphite oxide (GO) is an oxidation product of graphite. Due to the embedding of the functional groups in the carbon layers, GO exhibits rich intercalation chemistry but also loses the good electrical conductivity of graphite. To investigate the possibility of reducing GO by thermal treatment, the variation of the structures of the GO with the heat treatment conditions were studied by XRD, SEM, IR spectroscopy and elemental analysis. It is found that heating rate plays an important role in the structure of the thermal treated GO. When subjected to rapid heating, GO was decomposed into a very light soot containing many pores of different sizes in the range of 50?nm to 5μm. When subjected to slow heating, GO tended to return to the graphene structure. The higher the thermal treatment temperature, the closer the crystal structure of the pyrolyzed GO is to that of the graphite and the higher the electrical conductivity of the pyrolyzed GO. The fact that the electrical conductivity of GO can be higher than 1?S/cm when it is treated at a temperature higher than 180℃ suggesting that it is possible to use GO as a precursor to make conducting polymer/carbon nanocomposites.