A hierarchical NiPOx@NiFe LDH nanoarray for durable seawater oxidation

Seawater electrolysis, benefiting from the closeness to coastal areas, is recognized as a promising alternative for hydrogen (H 2 ) production to replace conventional technologies. However, the effectiveness of this method is limited by anode catalysts that exhibit high energy consumption and short lifespans due to chloride-induced chemical corrosion. Herein, we propose a hierarchical Ni phosphate@NiFe layered double hydroxide on Ni foam (NiPO x @NiFe LDH/NF) towards alkaline seawater oxidation (ASO). In terms of its unique hierarchical structure, NiPO x @NiFe LDH/NF delivers an industrial current density reaching up to 1 A cm −2 with 352 mV overpotential. Electrochemical experiments and in situ characterizations reveal that self-released PO 4 3− can act as a robust barrier for chloride ions adsorption through strong electrostatic repulsion, promoting unstable activity phase NiOOH drive at 1 A cm −2 for 600 h, farther than NiFe LDH/NF (75 h). Moreover, the honeycomb-like NiFe LDH shell facilitates the rapid and uniform release of O 2 bubbles, which enhances the mechanical stability of the electrode during long-term ASO. In general, this work offers valuable potential for designing an advanced anodic electrode with remarkable electrochemical performance and superior anti-corrosion for ASO.