Dynamic Ti-Cl Bonding Enables Corrosion-Resistant and Robust Seawater Electrolysis

Seawater electrolysis is essential for sustainable green hydrogen production but remains hindered by chloride ions (Cl-)-induced corrosion of electrode catalysts. Herein, we report an "adsorption-guided protection" strategy to achieve the trade-off between corrosion resistance and oxygen evolution reaction (OER) activity for NiFe layered double hydroxide (NiFe-LDH). Unlike conventional strategies that aim solely to repel Cl-, this strategy incorporates Ti dopants as preferential Cl--trapping centers. The Cl- dynamically adsorbed on Ti sites shields the OER-active Ni/Fe centers from corrosive attack and concurrently creates a localized electrostatic repulsion that inhibits further Cl- accumulation on the catalyst surface. NiFeTi-LDH exhibits high OER performance in alkaline seawater, achieving ampere-level current density with outstanding stability exceeding 3000 h. In situ spectroscopic analysis combined with theoretical calculations reveals that the Ti-Cl bonding not only lowers the energy barrier of the rate-determining step for OER intermediates but also induces an electrostatic repulsion effect that further excludes additional Cl- from approaching the active surface. This study offers insights into the reasonable design of high-performance and corrosion-resistant non-noble-metal catalysts for practical seawater electrolysis.