High-Density NiMnFe Hydroxide Hierarchical Nano-arrays for Industrial-level Electro-chemical Oxygen Evolution Reaction

Oxygen evolution reaction (OER) play a key role in the energy efficiency of electro-catalytic systems. However, the sluggish kinetics and accumulated gas slugs under the industrial operation condition limit the application of OER. Herein, Mn, Fe co-doped nickel hydroxide with highly dense hierarchical nano-sheets array is obtained through a simple and mild two-step etching strategy, which exhibits a remarkable OER performance. Doping Mn and Fe can modulate the electronic structure and redox behavior of active site, leading to an excellent intrinsic activity toward OER. Moreover, highly dense hierarchical array structure is conducive to provide more active sites and inhibit the accumulation of gas slugs under industrial current density. Thus, the obtained catalyst provides an impressing current density of 1.8 A cm−2 at a small overpotential of 370 mV and sustains the performance more than 100 h.