The conductivity and mobility of electrons would be the potential candidate behind the supercapacitors. If you may think about supercapacitors rGO would be ideal material than biomass carbon. The main reason would be the presence of SP2 hybridized carbon atoms with "pi" conjugation. You can use graphite as the starting material for synthesizing rGO. Also, considering the number of graphene layers in rGO, fewer layers gives extraordinary conductivity.
Article PHOTOCATALYTIC ACTIVITY OF GO/Fe3O4 FABRICATED BY SRI LANKAN...
Article PHOTOCATALYTIC ACTIVITY OF GO/Fe3O4 FABRICATED BY SRI LANKAN...
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