Rational hetero-interface design of Fe3N@Ni2Co-LDHs as high efficient electrocatalyst for oxygen evolution reaction

Abstract

The design of low-cost and efficient electrocatalysts is critical for oxygen evolution reaction (OER) to overcome the high overpotential and sluggish kinetics. Herein, a new non-precious metal electrocatalyst by synergistically coupling spindle-like Fe3N hollow nanorods with Ni2Co layered double hydroxides (Fe3N@Ni2Co-LDHs) was fabricated via annealing spindle-like Fe2O3 hollow nanorods in NH3 atmosphere, followed by refluxing in oil bath in the existence of Co(NO3)2·6H2O, Ni(NO3)2·6H2O, urea and polyvinylpyrrolidone (PVP). Impressively, the Fe3N@Ni2Co-LDHs nanohybrids with heterointerfaces shows remarkable OER performance with extremely low overpotential (only 240 mV to achieve a current density of 10 mA cm−2) and small Tafel slope (38.9 mV dec−1) for OER in alkaline medium. The enhanced OER performance could be attributed to the strong interfacial interaction between Fe3N and Ni2Co-LDHs, and improved electrical conductivity of the nanohybrids. This work might provide a feasible route for the development of efficient electrocatalysts with hetero-interfaces in renewable energy system.