Hydrangea-like nanosheets of Co(OH)2@NiFe-LDH/NF as an efficient electrocatalyst for the oxygen evolution reaction

Abstract

The rational design of an efficient and low-cost OER electrocatalyst is critical to overall water splitting. One of the well-known electrocatalysts is hydroxide. In this work, a simple and rapid hydrothermal–electrodeposition method was used to prepare Co(OH)₂@NiFe-LDH/NF. First, NiFe-LDH nanospheres were grown directly on a nickel foam (NF) surface via a hydrothermal method, and then NiFe-LDH/NF was converted into amorphous Co(OH)₂@NiFe-LDH/NF using an electrodeposition method. Particularly, the optimized material exhibits excellent OER performance in alkaline electrolytes. Overpotentials of 209 mV and 229 mV were required to drive current densities of 50 mA cm⁻² and 100 mA cm⁻². Besides, the material possesses a small Tafel slope (38.7 mV dec⁻¹) and displays outstanding durability for 100 h. This strategy opens up new possibilities for future non-precious metal OER electrocatalysts.