Scalable NiFe layered double hydroxides for efficient electrocatalytic seawater oxidation at high current density

Seawater electrolysis is emerging as a compelling route for green hydrogen production, but its practical implementation is severely limited by chloride-induced corrosion. Herein, we report a sulfate-intercalated NiFe layered double hydroxide on nickel foam (S-NiFe LDH/NF) as a scalable and efficient electrocatalyst for alkaline seawater oxidation (ASO), which achieves 1 A cm^-2 with a low overpotential of 375 mV and exhibits remarkable stability for 1800 h at this current density. MEA testing further confirms its durability, with stable operation over 200 h at 500 mA cm^-2. In situ Raman spectroscopy characterization and stability tests indicate that sulfate accelerates the formation of catalytically active γ-NiOOH and effectively repels chloride ions.