▎ 摘　　要

The effects of the washing conditions of graphite oxide (GO) and pyrolysis times on the thermal reduction of graphene are discussed in this article. Graphene samples that had been pyrolyzed for 30s and 5 min remained homogeneous in N,N-Dimethylformamide (DMF) for one month, whereas those samples that had been pyrolyzed for 20 and 40 min precipitated after one day. The conductivity of graphene increased with pyrolysis time. The resistivity of graphene thermally post-treated for 40 min reached 0.01 Omega cm. Whether or not GO was washed with deionized water had little effect on the structure and electric properties of graphene. (C) 2011 Elsevier B.V. All rights reserved.