▎ 摘　　要

Graphite oxide Was synthesized by the Hummers and Offemann method, followed by ultrasonic delamination in water to produce a stable hydrosol of graphene oxide sheets. The graphene oxide films were prepared from the hydrosol by a vacuum-assisted self-assembly technique. These films were further treated in a vacuum oven at different temperatures, and characterized by Fourier transform infrared spectroscopy, X-ray diffraction, Raman spectroscopy, and scanning and transmission electron microscopy. Results indicate that the graphene oxide films exhibit good electrical conductivity up to 527 S/m after the thermal treatment at temperatures from 130 to 200 degrees C. This environmentally friendly and easy approach is promising for the large scale preparation of graphene oxide films with no need of hydrazine and other toxic chemicals.