The influence of thermal treatment conditions on the structures and electrical conductivities of graphite oxide

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 50nm 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 1S/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.