High\nVolumetric\nEnergy Density Hybrid Supercapacitors Based on Reduced Graphene Oxide\nScrolls

Abstract

The low volumetric energy density\nof reduced graphene oxide (rGO)-based\nelectrodes limits its application in commercial electrochemical energy\nstorage devices that require high-performance energy storage capacities\nin small volumes. The volumetric energy density of rGO-based electrode\nmaterials is very low due to their low packing density. A supercapacitor\nwith enhanced packing density and high volumetric energy density is\nfabricated using doped rGO scrolls (GFNSs) as the electrode material.\nThe restacking of rGO sheets is successfully controlled through synthesizing\nthe doped scroll structures while increasing the packing density.\nThe fabricated cell exhibits an ultrahigh volumetric energy density\nof 49.66 Wh/L with excellent cycling stability (>10 000\ncycles).\nThis unique design strategy for the electrode material has significant\npotential for the future supercapacitors with high volumetric energy\ndensities.