Recent Progress in Seawater Splitting Hydrogen Production Assisted by Value-Added Electrooxidation Reactions

Electrolysis of abundant seawater resources is a promising approach for hydrogen production. However, the high-concentration chloride ion in seawater readily induces the chlorine evolution reaction (CER), resulting in catalyst degradation and decreased electrolysis efficiency. In recent years, the electrooxidation of small organic molecules (e.g., methanol), biomass-derived compounds (e.g., 5-hydroxymethylfurfural), and plastic monomers (e.g., ethylene glycol) has been seen to occur at lower potentials to substitute for the traditional oxygen evolution reaction (OER) and CER. This alternative approach not only significantly reduces energy consumption for hydrogen production but also generates value-added products at the anode. This review provides a comprehensive summary of research advancements in value-added electrooxidation reaction-assisted seawater hydrogen production technologies and emphasizes the underlying principles of various reactions and catalyst design methodologies. Finally, the current challenges in this field and potential future research directions are systematically discussed.