Protonated g-C3N4@polypyrrole derived N-doped porous carbon for supercapacitors and oxygen electrocatalysis

Preparation of high-performance carbon materials with an abundance of heteroatoms, edges, and defects for sustainable energy-conversion technologies, such as supercapacitors and oxygen reaction reduction (ORR), are still a challenge. Herein, we reported a facile strategy for the large-scale synthesis of nitrogen-doped porous carbon via carbonization of core-shell structured protonated g-C 3 N 4 @polypyrrole (P- g -C 3 N 4 @PPy) nanocomposites . Polypyrrole provided both the carbon and heteroatom sources, while P-g-C 3 N 4 acted not only as a sacrificial template but also as nitrogen sources. Porous carbon derived from P-g-C 3 N 4 @PPy (denoted as PCN@PPy-C-900) exhibited a specific capacitance of 350 F g −1 at a current density of 5 A g −1 and a high-rate capability (320 F g −1 ) at 20 A g −1 in 6 M KOH aqueous solution, as well as good long-term stability after 1000 cycles. In addition, PCN@PPy-C-900 also displayed excellent electrocatalytic performances in ORR in 0.1 M KOH aqueous solution. The excellent electrochemical performances provide guidance for the structure design of this promising class of multifunctional carbon-based materials which can be large scale applied to supercapacitors, ORR, and other fields.