Dynamic Hydrogen‑Bond Network Accelerates Lattice Oxygen Regeneration for High‑Current‑Density Seawater Electrolysis

ABSTRACT Seawater electrolysis for green H 2 production is hindered by the sluggish oxygen evolution reaction (OER) and chloride corrosion at the anode. Although the lattice oxygen mechanism (LOM) can effectively reduce the overpotential, the sluggish mass transport of OH − at high current densities disrupts the oxygen release–regeneration balance, ultimately leading to a trade‐off between activity and stability. Here, we demonstrate that yttrium (Y) and carboxylate co‐doping reconstruct the interfacial hydrogen‐bonding network of NiFe oxyhydroxide, dynamically accelerating OH − delivery and enabling rapid regeneration of lattice oxygen. This catalyst maintains a high LOM contribution (51.7%–54%) while achieving exceptional durability and Cl − resistance. In situ Raman, differential electrochemical mass spectrometry (DEMS), and rotating ring‐disk electrode (RRDE) analyses confirm rapid peroxide intermediate formation, lattice oxygen participation, and negligible chlorine evolution. The anion‐exchange membrane (AEM) electrolyzer delivers 1000 mA cm −2 at 1.79 V and operates stably for 800 h in alkaline seawater. This work establishes interfacial hydrogen‐bonding engineering as a generalizable strategy to break the activity–stability trade‐off for robust seawater electrolysis.