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-dopedporous carbons via carbonization of a mixture containing ferric citrate (FC) and ammonium chloride (NH4CI). 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 NaCI, the utilization of NH(4)C1 as porogen shows the best ORR performance in this work might due to the dual functions of NH(4)C1. Ferric citrate-NH4CI carbonized at 700 C-o 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 NH4CI are cheap and easily available, this work provides a facile and effective method to obtain carbons with superb electrochemical performances. (C) 2016 Elsevier Ltd. All rights reserved.