Reconstructing Interfacial H-Bond Networks via Surface Lewis-Base Silicate Species for Durable Seawater Oxidation

The interface between the electrocatalyst and electrolyte is critical in seawater electrolysis for hydrogen production, yet optimizing interfacial H-bond for enhanced catalytic activity and stability remains a significant challenge. This work demonstrates surface Lewis base (LB)-mediated reconstruction of interfacial water H-bond network within the electrochemical double layer toward enhanced seawater oxidation. The LB silicate species can be effectively immobilized on the surface of Ni(OH)₂ by electrochemical activation. In situ spectroscopy experiments show the LB-induced reconstruction of the H-bond network facilitates rapid OH⁻ enrichment, reduces local acidity, and prevents surface Cl⁻ corrosion on Ni(OH)₂, significantly improving seawater oxidation activity and long-term stability. Theoretical calculation further elucidates the key mechanism of the highly wettable silicate layers that can preferentially adsorb OH⁻ while resisting Cl⁻. The optimized Ni(OH)₂-Silicate achieves 121 mV reduction in overpotential at 200 mA cm⁻², stable operation for 620 h at industrial 1 A cm⁻², and robust activity for over 270 h at 1 A cm⁻² in alkaline anion-exchange membrane seawater electrolyzer. This LB-induced strategy paves an avenue of regulating the interfacial microenvironment for durable chloride-resisting electrocatalysis. © 2025 Wiley-VCH GmbH.