Efficient electrocatalytic oxygen evolution by Fe3C nanosheets perpendicularly grown on 3D Ni foams

Abstract

The development of efficient and earth-abundant catalyst for the oxygen evolution reaction (OER) is an important challenge for the renewable energy research community. Here, we report a facile method to design a nanosheet-like structure of Fe3C, perpendicularly grown on Ni foam (NF) as a catalyst for OER by hydrothermal reaction and annealing treatment at a low temperature. The synthesized Fe3C has good conductivity, small charge transfer resistance (Rct), high active site density, and excellent stability, which make it highly efficient OER catalyst. Fe3C/NF has a low overpotential of 262 mV at a current density of 10 mA cm−2 and a small Tafel slope of 49 mV dec−1. Remarkably, Fe3C/NF also has good electrochemical stability, which helps maintain its activity in 1.0 M KOH solution for at least 100 h. Therefore, the simple method to prepare perpendicularly grown Fe3C on a NF substrate can enhance the OER properties, which make Fe3C/NF a promising material for replacing noble metal-based catalysts for OER applications.