Recent advances in Ni‐Fe (Oxy)hydroxide electrocatalysts for the oxygen evolution reaction in alkaline electrolyte targeting industrial applications

Abstract Due to its high gravimetric energy density, abundance, wide applicability, and potential to be a zero‐carbon emission energy carrier, hydrogen is considered to be highly important for future sustainability. Currently, 96% of hydrogen is produced from fossil fuels, with relatively low purity and high associated CO 2 emissions. Only 4% of hydrogen is produced by water electrolysis with high purity mainly due to the inefficiency of oxygen evolution reaction (OER). Therefore developing high performance OER electrocatalysts for water electrolysis powered by renewables is an urgent and crucial task for long‐term sustainability. Recently, low‐cost Ni‐Fe (oxy)hydroxides have demonstrated high OER activities and great potentials for hydrogen production through water electrolysis. This review commences with discussion of the mechanism of the OER and OER evaluation criteria. This is followed by a brief history of Ni‐Fe (oxy)hydroxides. Most importantly, the recent development of Ni‐Fe (oxy)hydroxide OER electrocatalysts in terms of material design, synthesis methods, morphology, and electrochemical performance, is comprehensively reviewed. In addition, in‐situ techniques for the characterization of Ni‐Fe (oxy)hydroxide OER electrocatalysts are introduced. Finally, strategies for the rational design of improved Ni‐Fe (oxy)hydroxide OER electrocatalysts for industrial water electrolysis are also discussed.