A novel way to synthesize nitrogen and oxygen co-doped porous carbon for high performance supercapacitors

Nitrogen and oxygen co-doped porous carbon materials were successfully synthesized by one-step pyrolysis of the mixture of polyacrylamide and potassium citrate. The optimized porous carbon material (NPC-700-2-2) exhibits high specific surface area, interconnected hierarchical porous structure and abundant nitrogen/oxygen functional groups (14.7 at.% O and 1.5 at.% N). Benefiting from their synergistic effect, the NPC-700-2-2 electrode displays a high specific capacitance of 351 F g(-1) at 1 A g(-1), excellent rate capability (226 F g(-1) at 50 A g(-1)) and excellent cycling stability (retaining 98.4% after 10,000 cycles) in 6 M KOH aqueous electrolyte. Moreover, the assembled symmetric supercapacitor using NPC-700-2-2 as positive and negative electrodes exhibits a high energy density of 21.4 Wh kg(-1) and excellent cycling stability in 1 mol L-1 Na2SO4 aqueous electrolyte. These exciting results exhibit a facile and low-cost way for the synthesis of heteroatoms doped porous carbon materials for high performance supercapacitors.