Confining\nRedox Electrolytes in Functionalized Porous\nCarbon with Improved Energy Density for Supercapacitors

Abstract

It is a big challenge\nto improve the energy density of the carbon-based\nsupercapacitors for wide applications. In this work, considering the\nproperties of redox electrolytes, functionalized porous carbon has\nbeen synthesized with interconnected pores and oxygen functional groups,\nwhich is employed to well hold the redox electrolyte ions. As a result,\nthe functionalized porous carbon shows a high capacitance of 454 F\ng^–1 at a current density of 1 A g^–1 and can maintain 88% of the initial capacitance after 10 000\ncharge–discharge cycles at 10 A g^–1. Especially,\nthe as-prepared asymmetric supercapacitor obtains high energy density\nof 36.9 W h kg^–1 at the power density of 225 W kg^–1. This new design strategy by coordinating carbon\nmaterials with the redox electrolytes will guide the development of\nhigh-energy density supercapacitors.