Surface-Engineering strategies for chloride-resistant oxygen evolution electrocatalysts in direct seawater electrolysis

Abstract

Direct seawater electrolysis represents a sustainable pathway for large-scale hydrogen production but is severely limited by the corrosion and selectivity challenges of oxygen evolution reaction (OER) catalysts in chloride-rich environments. Surface engineering has emerged as a powerful approach to simultaneously enhance catalytic activity, stability, and selectivity by tailoring the surface composition, electronic structure, and interfacial microenvironment of catalysts. This review comprehensively summarizes the recent advances in four representative surface modification strategies, namely, core–shell structure construction, surface atomic doping, surface functionalization, and heterostructure interface engineering. This review elucidates their underlying enhancement mechanisms, such as physical shielding, electrostatic repulsion, and electronic modulation. The advantages and limitations of each strategy are critically analyzed, highlighting how rational surface design can mitigate Cl⁻-induced corrosion, suppress the competitive chlorine evolution reaction, and promote long-term operational durability. Finally, the review discusses the current challenges and future directions toward achieving scalable, corrosion-resistant OER catalysts for efficient and durable direct seawater electrolysis.