Mechanochemical preparation of graphene nanosheets and their supercapacitor applications

•Gram scale production of graphene sheets was obtained via mechnochemical method.•HR-TEM micrographs revealed the formation of few layered graphene sheets.•XPS and Raman analysis confirmed the reduction of GO into graphene sheets.•Graphene sheets exhibited a specific capacitance of 169F/g. A facile method for the preparation of graphene nanosheets via mechanochemical reduction of graphene oxide (GO) has been reported. XPS and Raman analyses revealed the removal of oxygenated functional groups and the restoration of sp2 domains in graphene after the mechanochemical reaction. Cyclic voltammetry curves showed a rectangular behavior suggesting the presence of double layer capacitance in the graphene electrodes. Graphene electrodes delivered a specific capacitance of 169F/g as observed from the charge–discharge analysis at a current density of 1mA/cm2. The cyclic stability analysis revealed that about 98% of its initial capacitance was retained after 1000 cycles.