Abstract
Supercapacitors, as a new type of green electrical energy storage device, are a potential solution to environmental problems created by economic development and the excessive use of fossil energy resources. In this work, nitrogen/oxygen (N/O)-doped porous carbon materials for high-performance supercapacitors are fabricated by calcining and activating an organic crosslinked polymer prepared using polyethylene glycol, hydroxypropyl methylcellulose, and 4,4-diphenylmethane diisocyanate. The porous carbon exhibits a large specific surface area (1589 m(2)·g(-1)) and high electrochemical performance, thanks to the network structure and rich N/O content in the organic crosslinked polymer. The optimized porous carbon material (C(OCLP-4.5)), obtained by adjusting the raw material ratio of the organic crosslinked polymer, exhibits a high specific capacitance (522 F·g(-1) at 0.5 A·g(-1)), good rate capability (319 F·g(-1) at 20 A·g(-1)), and outstanding stability (83% retention after 5000 cycles) in a three-electrode system. Furthermore, an energy density of 18.04 Wh·kg(-1) is obtained at a power density of 200.0 W·kg(-1) in a two-electrode system. This study demonstrates that organic crosslinked polymer-derived porous carbon electrode materials have good energy storage potential.