Emerging electrocatalysts and electrolyzers for high-current-density direct seawater electrolysis

Abstract

Direct seawater electrolysis (DSE) provides a promising technical route for green hydrogen production using renewable energy. However, due to the complex composition of seawater, DSE suffers from some issues such as competitive chloride oxidation reactions, sluggish reaction kinetics, interference from insoluble solids and precipitates, and material corrosion. These greatly suppress the catalytic activity, selectivity and long-term stability of electrolysis system, hindering the large-scale development of this technology. Based on the analysis the challenges facing in DSE, this review summarizes the design and synthesis trends of electrocatalysts in recent years, providing some effective strategies for improving the chloride resistance, activity and selectivity, and discussing their advantages and limitations. We elaborate on the operation mechanisms, challenges and recent advances of electrolyzers in seawater electrolysis. Finally, a perspective regarding the future research directions of DSE technology are provided.