One-step solid state preparation of reduced graphene oxide

We have developed an easy and scalable chemical reduction method assisted by microwave irradiation for the synthesis of reduced graphene oxide (RGO) nanosheets in solid state. The as-synthesized RGO is characterized by Fourier transform infrared spectroscopy, Raman spectroscopy, thermogravimetry, X-ray diffraction, X-ray photoelectron spectroscopy and atomic force microscopy. It is revealed that the bulk of the oxygen-containing functional groups are removed from graphene oxide with this one-step reduction method and monolayer RGO sheets are got from its N,N-dimethyl formamide solution. It is found that the ammonium bicarbonate plays a key role in the preparation of RGO. Considering the analysis results, a mechanism for the formation of RGO is proposed. Besides being eco-friendly, when compared to previous chemical techniques, this process has several advantages like low cost, simplicity and short processing times, which may find practical applications in the preparation of graphene-based composites. (C) 2012 Elsevier Ltd. All rights reserved.