Nickel-Iron-Layered Double Hydroxide Electrocatalyst with Nanosheets Array for High Performance of Water Splitting.

Developing high-performance and cost-competitive electrocatalysts have great significance for the massive commercial production of water-splitting hydrogen. Ni-based electrocatalysts display tremendous potential for electrocatalytic water splitting. Herein, we synthesize a novel NiFe-layered double hydroxide (LDH) electrocatalyst in nanosheets array on high-purity Ni foam. By adjusting the Ni/Fe ratio, the microstructure, and even the behavior of the electrocatalyst in the oxygen evolution reaction (OER), changes significantly. The as-obtained material shows a small overpotential of 223 mV at 10 mAcm as well as a low Tafel slope of 48.9 mV·dec in the 1 M KOH electrolyte. In addition, it can deliver good stability for at least 24 h of continuous working at 10 mAcm. This work proposes a strategy for engineering catalysts and provides a method for the development of other Ni-based catalysts with excellent performance.