Iron Foam-Derived Nickel-Iron Hydroxide Nanosheets via Solution Etching as Robust Catalysts for Alkaline Seawater Oxidation

Traditional electrocatalyst fabrication techniques, such as hydrothermal/solvothermal method and electrodeposition may result in excessive energy consumption and safety concerns that hinder their scalability and practical application. Herein, we report a facile room-temperature solution corrosion method to synthesize nickel-iron hydroxide (NiFe(OH)x) nanosheets on by using five different nickel salts (NiCl2、NiSO4、Ni(NO3)2、(CH3COO)2Ni、NiF2) for efficient seawater oxidation. By simply immersing Fe foam (FF) in the nickel salt solution, we achieved in situ growth of ultrathin NiFe(OH)x nanosheets with abundant active sites and enhanced charge transfer properties.The as-prepared NiFe(OH)x/FF electrode exhibits excellent electrocatalytic activity for the oxygen evolution reaction (OER) in alkaline seawater oxidation, delivering high current density at low overpotentials with remarkable durability. This work provides a simple and scalable strategy for designing cost-effective electrocatalysts for seawater splitting, offering potential applications in renewable hydrogen production.