Iron-doped cobalt nitride nanoparticles (Fe–Co3N): An efficient electrocatalyst for water oxidation

The exploration of efficient, low-cost and earth-abundant oxygen-evolution reaction (OER) electrocatalysts and the understanding of the intrinsic mechanism are important to advance the clean energy conversion technique based on electrochemical water oxidation. In this work, Fe-doping Co 3 N catalysts were successfully synthesized by a simple nitridation reaction of the Co 3- x Fe x O 4 precursor. This material exhibited a low overpotential of 294 mV at a current density of 10 mA cm −2 , and a small Tafel slope of 49 mV dec −1 in 1 M KOH solution, superior to the performance of Co 3 N and IrO 2 . As revealed by the spectroscopic and electrochemical analyses, the enhanced OER performance mainly originates from the electronic modulation induced by the incorporation of Fe into Co 3 N, benefitting the formation of CoOOH as active surface species and thus facilitating the OER process. These findings also demonstrate the introduction of heterogeneous element is a simple and effective strategy to regulate the OER property of the cobalt nitrides (Co 3 N) catalysts. • It is the first report to research Fe-doping Co 3 N as OER catalysts. • Fe-doping catalysts exhibited superior performance than Co 3 N and IrO 2 . • The enhanced activity of OER is mainly due to the Fe inducing electronic modulation.