Synthesis of graphene from dry ice in flames and its application in supercapacitors

We have synthesized graphene by reducing carbon dioxide in magnesium and calcium metal flames. The as-prepared graphene has been used as conductive additive to improve the electrical conduction of activated carbon-based supercapacitor electrodes. The graphene/activated carbon composite electrode showed an outstanding specific capacitance of 220 and 180 F g−1 at a current density of 0. 1 A g−1 in 6 M KOH electrolyte when using graphene obtained in magnesium and calcium flames, respectively.