Synergistic Morphological and Electronic Engineering of NiFeOOH via Ultrafast Room Temperature Fabrication for Enhanced OER

ABSTRACT Low‐cost, high‐performance oxygen evolution reaction (OER) catalysts are considered pivotal to enabling the industrial‐scale production of green hydrogen via water electrolysis. Herein, we report an ultrafast (30 s) room‐temperature approach to fabricating a biomimetic NiFeOOH electrocatalyst directly on nickel foam. The resulting material featuring a chloroplast‐inspired hierarchical nanosheet architecture and is enriched with oxygen vacancies. This unique design achieves exceptional OER activity, requiring an overpotential of only 260 mV to deliver 100 mA cm −2 , alongside remarkable stability for over 100 h. The enhanced mechanism was unraveled through in situ Raman spectroscopy and electrochemical impedance spectroscopy, which revealed accelerated reaction kinetics and facilitated structural evolution. Density functional theory calculations further verified that the oxygen vacancies effectively lower the energy barrier of the rate‐determining step. This work provides a scalable strategy for integrating bio‐inspired morphology and electronic modulation in high‐performance catalyst design for efficient water oxidation.