Ultra-stable seawater oxidation at 1.5 A cm^-2 enabled by heptafluorotantalate intercalated NiFe layered double...

Seawater electrolysis is a facile, economical, and ecologically friendly approach for large-scale hydrogen production. However, the presence of chloride ions (Cl^-) in seawater can cause severe anode corrosion, which hinders its further application. Herein, a heptafluorotantalate (TaF₇^2-) intercalated NiFe layered double hydroxide on Ni foam (TF-NiFe LDH/NF) is proposed for efficient and durable alkaline seawater oxidation (ASO). Such TF-NiFe LDH/NF requires an overpotential of only 375 mV to achieve a current density (j) of 1 A cm^-2 and maintains stable operation for 1000 h at a j of 1.5 A cm^-2. In situ Raman characterization and stability tests indicate that TaF₇^2- can not only facilitate the dynamic reconstruction process of the catalyst but also effectively repel Cl^- at ampere-level j. This study highlights a novel anion (TaF₇^2-) intercalation strategy, providing new insights into the design of efficient and stable electrocatalysts, thus offering a new approach to enhance corrosion resistance for ASO.