Abstract
A facile and environmentally friendly approach to produce self-doped hierachically porous carbon as electrode material for high-performance supercapacitor was demonstrated. 3D honeycomb-like hierarchically porous carbon was successfully obtained by one-step carbonization and activation of sodium carboxymethyl cellulose (CMC) via K2CO3. With the optimized temperature of carbonization and activation, the porous carbon material achieved well-shaped hierarchically pores (micro-, meso and macropores) like a honeycomb, ultrahigh specific surface area (1666 m2·g-1), as well as highly O-self-doping (3.6 at.%), endowing an excellent electrochemical properties for the electrode in three-electrode system. The porous carbon electrode material delivered a high specific capacitance of 300.8 F·g-1 at 1 A·g-1, an eminent rate capability of 228.4 F·g-1 at the current density up to 20 A·g-1 and outstanding cycle stability of 94.3% retention after 10000 cycles. Therefore, the CMC derived hierarchical porous carbon activated by K2CO3 would have promising foreground in application of supercapacitors.
One-step cathodic electrodeposition of a cobalt hydroxide–graphene nanocomposite and its use as a high performance supercapacitor electrode material