Oxalic acid assisted expansion-reduction exfoliation of graphene oxide into graphene nanosheets

A novel approach to prepare graphene nanosheets was developed by exfoliating graphene oxide (GO) assisted with oxalic acid (H2C2O4). The expansion and reduction of GO were synchronously fulfilled through the decomposition of H2C2O4 impregnated into the interlayer of GO. The structure of the as-exfoliated graphene nanosheets were determined by a series of characterizations. The results showed that the as-exfoliated graphene nanosheets possessed ca. 10-layered thickness and the lower oxygen content. The mechanism was proposed that H2C2O4 played a role of the expansion-reduction associated effect in exfoliation.