High-Performance Supercapacitors Based on Poly(ionic liquid)-Modified Graphene Electrodes

We report a high-performance supercapacitor incorporating a poly(ionic liquid) modified reduced; graphene oxide (PIL:RG-0) electrode and an ionic liquid (IL) electrolyte (specifically, 1-ethyl-3-methylimidazolium bis(trifluoromethylsuffonyl)amide or EMIM-NTf2). PIL:RG-0 provides enhanced compatibility with the IL thereby increasing the effective electrode surface area accessible to electrolyte ions. The supercapacitor assembled. with PIL:RG-0 electrode and EMIM-NTf2 electrolyte showed a stable electrochemical response up to 35 V operating voltage and was capable of yielding a maximum energy density of 65 W . h/kg with a power density of 24 kW/kg. These results demonstrate the potential of the PIL:RG-0 material as an electrode In high-performance supercapacitors.