Electrodeposited Ternary Metal (Oxy)Hydroxide Achieves Highly Efficient Alkaline Water Electrolysis Over 1000 h Under Industrial Conditions

Large-scale green hydrogen production technology, based on the electrolysis of water powered by renewable energy, relies heavily on non-precious metal oxygen evolution reactions (OER) electrocatalysts with high activity and stability under industrial conditions (6 M KOH, 60°C–80°C) at large current density. Here, we construct Fe and Co co-incorporated nickel (oxy)hydroxide (Fe 2.5 Co 2.5 Ni 10 O y H z @NFF) via a multi-metal electrodeposition, which exhibits outstanding OER performance (overpotential: 185 mV @ 10 mA cm −2 ). Importantly, an overwhelming stability for more than 1100 h at 500 mA cm −2 under industrial conditions is achieved. Our combined experimental and computational investigation reveals the surface-reconstructed γ-NiOOH with a high valence state is the active layer, where the optimal (Fe, Co) co-incorporation tunes its electronic structure, changes the potential determining step, and reduces the energy barrier, leading to ultrahigh activity and stability. Our findings demonstrate a facile way to achieve an electrocatalyst with high performance for the industrial production of green hydrogen.