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

Abstract

Abstract 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.