Construction of a hierarchical NiFe layered double hydroxide with a 3D mesoporous structure as an advanced electrocatalyst for water oxidation

Abstract

The exploitation of highly active, cost-effective, and stable electrocatalysts toward the oxygen evolution reaction (OER) is essential for the development of various energy conversion and storage systems, such as water splitting and metal–air batteries. In this report, 3D mesoporous NiFe layered double hydroxide (LDH) microclusters with a hierarchical architecture are in situ grown on Ni foam through a facile and cost-effective one-step hydrothermal method by using Ni foam as both a Ni source and support. Thanks to the unique architecture and strong synergistic electronic effect between Ni and Fe, the as-synthesized NiFe LDH exhibits remarkable catalytic OER performance with a small overpotential of 211 mV to achieve a current density of 10 mA cm⁻², which outperforms most of the reported non-noble metal-based catalysts and almost all the documented LDH-based electrocatalysts.