The effect of thermal treatment at low temperatures on graphene oxide films

Abstract

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 ℃.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.