Electrosynthesis of chlorine from seawater-like solution through single-atom catalysts

• Published in: Nature communications Vol. 14; no. 1; p. 2475
• Main Authors: Liu, Yangyang, Li, Can, Tan, Chunhui, Pei, Zengxia, Yang, Tao, Zhang, Shuzhen, Huang, Qianwei, Wang, Yihan, Zhou, Zheng, Liao, Xiaozhou, Dong, Juncai, Tan, Hao, Yan, Wensheng, Yin, Huajie, Liu, Zhao-Qing, Huang, Jun, Zhao, Shenlong
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 29-04-2023; Nature Publishing Group; Nature Portfolio
• Subjects: 140/146; 639/166/898; 639/301/299/886; 639/638/161/886; Catalysis; Catalysts; Chemical analysis; Chemical industry; Chemical synthesis; Chloride ions; Chlorine; Current density; Electrocatalysis; Electrocatalysts; Electrochemistry; Electrodes; Energy consumption; Evolution; Flow stability; Free energy; Humanities and Social Sciences; multidisciplinary; Ruthenium; Science; Science (multidisciplinary); Seawater; Single atom catalysts; Sodium chloride; Water analysis
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-023-38129-w

The chlor-alkali process plays an essential and irreplaceable role in the modern chemical industry due to the wide-ranging applications of chlorine gas. However, the large overpotential and low selectivity of current chlorine evolution reaction (CER) electrocatalysts result in significant energy consumption during chlorine production. Herein, we report a highly active oxygen-coordinated ruthenium single-atom catalyst for the electrosynthesis of chlorine in seawater-like solutions. As a result, the as-prepared single-atom catalyst with Ru-O
4
moiety (Ru-O
4
SAM) exhibits an overpotential of only ~30 mV to achieve a current density of 10 mA cm
−2
in an acidic medium (pH = 1) containing 1 M NaCl. Impressively, the flow cell equipped with Ru-O
4
SAM electrode displays excellent stability and Cl
2
selectivity over 1000 h continuous electrocatalysis at a high current density of 1000 mA cm
−2
. Operando characterizations and computational analysis reveal that compared with the benchmark RuO
2
electrode, chloride ions preferentially adsorb directly onto the surface of Ru atoms on Ru-O
4
SAM, thereby leading to a reduction in Gibbs free-energy barrier and an improvement in Cl
2
selectivity during CER. This finding not only offers fundamental insights into the mechanisms of electrocatalysis but also provides a promising avenue for the electrochemical synthesis of chlorine from seawater electrocatalysis.
Chlor-alkali process plays an important role in the chemical industry. However, large overpotential and low selectivity of currently used catalysts lead to high energy consumption. Here the authors report Ru-O
4
single site catalysts for chlorination evolution with 1000 h stability at 1000 mA cm
−2
in a seawater-like environment.