Nitrogen-Mediated Lanthanide Electronic Perturbations Boost Oxygen Spillover on Nickel–Iron Electrocatalysts for Ultralong-Lifetime Oxygen Evolution

Highly active oxygen evolution reaction catalysts allow high-efficiency water electrolysis for green hydrogen production, but prevalently encounter severe activity degradation when operated at industrial ampere-level current densities. Here we demonstrate configurating heterostructure interfaces in nickel–iron-based catalysts to exceptionally improve their oxygen evolution reaction electrocatalytic durability at >1000 mA cm–2 by incorporating nitrogen-doped lanthanide oxides, which enable supplementary oxygen intermediate spillover via a modified lattice oxygen mechanism. By virtue of nitrogen-mediated flexible electronic perturbation of cerium, there reversibly form oxygen vacancies in nitrogen-doped cerium dioxide to sustainably accommodate the oxygen intermediates spilled from nickel–iron (oxy)hydroxide and boost *O–O coupling and desorption kinetics, which significantly suppresses the formation of soluble high-valence iron species. This enlists nickel–iron-based heterostructure electrocatalysts with a hierarchical nanoporous architecture to exhibit outstanding oxygen evolution reaction activity and durability, achieving 2000 mA cm–2 at an ultralow overpotential of 310 mV and maintaining stability for >9000 h in 1 M KOH.