Stabilizing the Lattice Oxygen Oxidation Pathway via a Dynamic Hydrogen-Bond Network for Industrial-Current Seawater...

Seawater electrolysis for green hydrogen is severely limited by the competing chloride oxidation reaction (ClOR) and the sluggish kinetics of oxygen evolution reaction (OER). This study introduces a lattice renormalization strategy to direct the reconstruction of Co-Mo-O catalysts in alkaline electrolyte, effectively shifting the OER pathway from the traditional adsorbate evolution mechanism (AEM) to the more efficient lattice oxygen mechanism (LOM). Selective Mo leaching induces the construction of a CoOOH/Co(OH)₂ with a stable Co³⁺-O-Co²⁺ electron-withdrawing chain, which significantly enhances Co-O covalency and activates lattice oxygen. The optimized catalyst, r-CoO_xH_y@NF, achieves low overpotentials of 330 and 380 mV at 500 and 1000 mA cm^{- 2} in simulated alkaline seawater, respectively. When configured into a membrane electrode assembly (MEA) electrolyzer, the system attains a low cell voltage of 1.66 V at 1.0 A cm^{- 2} for 480 h. In situ characterization and theoretical analysis reveal a "lattice oxygen-hydrogen-bonding network" synergy, where dynamically evolving hydrogen-bonding network at the interface not only facilitates rapid proton transfer but also electronically modulates the lattice oxygen orbitals via polarization effects, with stabilizing the LOM pathway and conferring superior chloride resistance. This work underscores the pivotal role of metal-ligand covalency and interfacial microenvironment in steering reconstruction pathways for industrial seawater splitting.