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

Yangyang Liu; Can Li; Chunhui Tan; Zengxia Pei; Tao Yang; Shuzhen Zhang; Qianwei Huang; Yihan Wang; Zheng Zhou; Xiaozhou Liao; Juncai Dong; Hao Tan; Wensheng Yan; Huajie Yin; Zhao-Qing Liu; Jun Huang; Shenlong Zhao

doi:10.1038/s41467-023-38129-w

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

Nat Commun. 2023 Apr 29;14(1):2475. doi: 10.1038/s41467-023-38129-w.

Authors

Yangyang Liu^#^{1

2}, Can Li^#³, Chunhui Tan^#², Zengxia Pei², Tao Yang⁴, Shuzhen Zhang², Qianwei Huang⁵, Yihan Wang^{1

2}, Zheng Zhou², Xiaozhou Liao⁵, Juncai Dong⁶, Hao Tan⁷, Wensheng Yan⁸, Huajie Yin⁹, Zhao-Qing Liu¹⁰, Jun Huang¹¹, Shenlong Zhao^{12

13}

Affiliations

¹ CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China.
² School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, NSW, 2006, Australia.
³ Key Laboratory of Rare Earth Optoelectronic Materials and Devices of Zhejiang Province, College of Optical and Electronic Technology, China Jiliang University, Hangzhou, 310018, China.
⁴ Department of Mechanical Engineering, University of Aveiro, Aveiro, 3810-93, Portugal.
⁵ School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, Sydney, NSW, 2006, Australia.
⁶ Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China.
⁷ National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230029, China. talkhao@ustc.edu.cn.
⁸ National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230029, China.
⁹ Institute of Solid-State Physics, Chinese Academy of Sciences, Hefei, 230031, China.
¹⁰ School of Chemistry and Chemical Engineering/Guangzhou Key Laboratory for Clean Energy and Materials/Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou, 510006, China.
¹¹ School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, NSW, 2006, Australia. jun.huang@sydney.edu.au.
¹² CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China. shenlong.zhao@sydney.edu.au.
¹³ School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, NSW, 2006, Australia. shenlong.zhao@sydney.edu.au.

^# Contributed equally.

Abstract

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-O₄ moiety (Ru-O₄ 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-O₄ SAM electrode displays excellent stability and Cl₂ 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 RuO₂ electrode, chloride ions preferentially adsorb directly onto the surface of Ru atoms on Ru-O₄ SAM, thereby leading to a reduction in Gibbs free-energy barrier and an improvement in Cl₂ 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.