Rational Design of a Stable Fe‐rich Ni‐Fe Layered Double Hydroxide for the Industrially Relevant Dynamic Operation of Alkaline Water Electrolyzers

Nickel-iron layered double hydroxides (Ni-Fe LDHs) consist of stacked Fe3+-doped positively charged Ni-hydroxide layers containing charge-balancing anions and water molecules between the layers. Although Ni-Fe LDHs are highly active in oxygen evolution reaction (OER) under alkaline conditions, their poor operational stability remains an issue. Herein, based on density functional theory calculations, it is proposed that inclusion a higher Fe content (>40%) than theoretical Fe3+ limit (≈25%) permitted by can lead to improved structural stability. An Fe-rich LDH electrode therefore prepared via growth strategy controlled corrosion substrate, enabling incorporation additional Fe2+ into Ni2+-Fe3+ structure. Indeed, microstructural elemental analysis confirm presence Fe2+. This not only offers low OER overpotential (≈270 mV at 200 mA cm−2) but also exhibits excellent dynamic operating environments without any significant performance degradation or metal ion dissolution. Finally, practical feasibility demonstrated single-cell (34.56 cm2) operation. These findings expected aid development reliable electrodes for use commercial electrolyzers.