Recent Advancements on Key Electrode Materials of Seawater Electrolysis for Hydrogen Production

Direct seawater electrolysis offers a promising route for sustainable hydrogen production by utilizing abundant seawater and renewable energy. However, the complex chemical composition of seawater, particularly high chloride ion concentrations, poses severe challenges during direct electrolysis, including anode corrosion and competitive side reactions like the chlorine evolution reaction (CER), which impair efficiency and durability. Consequently, stringent demands are focused on developing advanced electrocatalysts resistant to corrosion, selectively promoting the oxygen evolution reaction (OER) over CER, and designing a novel overall system. This chapter reviews the critical breakthroughs and technological directions in seawater electrolysis materials, incorporating recent research advancements from four key perspectives. We outline the fundamental principles of seawater electrolysis and then address the critical challenges of seawater electrolysis: competitive anodic reactions (especially CER) and halogen-induced corrosion. Subsequently, we detail the catalyst design strategies, including (1) constructing Cl−-blocking protective layers, (2) enhancing catalytic activity and selectivity, and (3) coupling non-chlorine oxidation reactions. Future research should focus on designing corrosion-resistant, high-activity electrodes and integrated systems while unraveling multi-reaction mechanisms and standardizing tests in real seawater.