Heterogeneous polymer of aniline and benzoquinone enabled high energy density of graphene-based supercapacitors

Abstract

Polyaniline and benzoquinone with powerful electrochemical activity and reversibility were widely used to boost specific capacitance of graphene electrode material and energy density of the corresponding supercapacitor devices. Inspired by these previous reports, herein, a novel heterogeneous polymer (polyAHQDME) containing both aniline units and benzoquinone ones were designed and synthesized, and finally grafted on reduced graphene oxide (rGO) framework. As expected, redox-active polyAHQDME modifier enabled rGO with an ultrahigh specific capacitance of 685.4 F g−1, five folds bare rGO counterpart. When assembled into symmetric two-electrode devices in quasi-solid-state aqueous and organic electrolytes, respectively, the key energy density parameter could reach as high as 21.6 and 100.6 Wh kg−1, outperforming most recently-reported modified carbon electrode materials.