Ferric citrate-derived N-doped hierarchical porous carbons for oxygen reduction reaction and electrochemical supercapacitors

This work reports a facile strategy for the preparation of Nitrogen-doped porous carbons via carbonization of a mixture containing ferric citrate (FC) and ammonium chloride (NH 4 Cl). FC provides carbon and iron element sources, while ammonium chloride acts as both the porogen and nitrogen dopant during the carbonization process . The formed hierarchical porous structures facilitate the ion diffusion/transport, and nitrogen-doping provides more active sites, which contribute to both oxygen reduction reaction (ORR) and supercapacitor applications. Compared with KOH and NaCl, the utilization of NH 4 Cl as porogen shows the best ORR performance in this work might due to the dual functions of NH 4 Cl. Ferric citrate-NH 4 Cl carbonized at 700 °C exhibits good capacity of 242 F g −1 and stability in 6 M KOH at a current density of 1 A g −1 . Since both FC and NH 4 Cl are cheap and easily available, this work provides a facile and effective method to obtain carbons with superb electrochemical performances.