An overview and recent advances in electrocatalysts for direct seawater splitting

Abstract

In comparison to pure water, seawater is widely accepted as an unlimited resource. The direct seawater splitting is economical and eco-friendly, but the key challenges in seawater, especially the chlorine-related competing reactions at the anode, seriously hamper its practical application. The development of earth-abundant electrocatalysts toward direct seawater splitting has emerged as a promising strategy. Highly efficient electrocatalysts with improved selectivity and stability are of significance in preventing the interference of side reactions and resisting various impurities. This review first discusses the macroscopic understanding of direct seawater electrolysis and then focuses on the strategies for rational design of electrocatalysts toward direct seawater splitting. The perspectives of improved electrocatalysts to solve emerging challenges and further development of direct seawater splitting are also provided.

Graphical abstract

Keywords

seawater splitting / electrocatalysts / oxygen evolution reaction / hydrogen evolution reaction / chlorine chemistry

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Acknowledgments

This work was supported by the National Natural Science Foundation of China (Grant Nos. 22111530112 and 21875118), the Natural Science Foundation of Tianjin (Grant No. 19JCZDJC37700), and the Foundation of State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering (Grant No. 2020-KF-22).

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