Spatial decoupling of bromide-mediated process boosts propylene oxide electrosynthesis

Mingfang Chi; Jingwen Ke; Yan Liu; Miaojin Wei; Hongliang Li; Jiankang Zhao; Yuxuan Zhou; Zhenhua Gu; Zhigang Geng; Jie Zeng

doi:10.1038/s41467-024-48070-1

Spatial decoupling of bromide-mediated process boosts propylene oxide electrosynthesis

Nat Commun. 2024 Apr 29;15(1):3646. doi: 10.1038/s41467-024-48070-1.

Authors

Mingfang Chi^#¹, Jingwen Ke^#¹, Yan Liu^#¹, Miaojin Wei¹, Hongliang Li¹, Jiankang Zhao¹, Yuxuan Zhou¹, Zhenhua Gu¹, Zhigang Geng², Jie Zeng^{3

4

5

6

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Affiliations

¹ Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, 230026, Hefei, Anhui, P. R. China.
² Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, 230026, Hefei, Anhui, P. R. China. gengzg@ustc.edu.cn.
³ Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, 230026, Hefei, Anhui, P. R. China. zengj@ustc.edu.cn.
⁴ CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, University of Science and Technology of China, 230026, Hefei, Anhui, P. R. China. zengj@ustc.edu.cn.
⁵ Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, University of Science and Technology of China, 230026, Hefei, Anhui, P. R. China. zengj@ustc.edu.cn.
⁶ Department of Chemical Physics, University of Science and Technology of China, 230026, Hefei, Anhui, P. R. China. zengj@ustc.edu.cn.
⁷ School of Chemistry & Chemical Engineering, Anhui University of Technology, 243002, Ma'anshan, Anhui, P. R. China. zengj@ustc.edu.cn.

^# Contributed equally.

Abstract

The electrochemical synthesis of propylene oxide is far from practical application due to the limited performance (including activity, stability, and selectivity). In this work, we spatially decouple the bromide-mediated process to avoid direct contact between the anode and propylene, where bromine is generated at the anode and then transferred into an independent reactor to react with propylene. This strategy effectively prevents the side reactions and eliminates the interference to stability caused by massive alkene input and vigorously stirred electrolytes. As expected, the selectivity for propylene oxide reaches above 99.9% with a remarkable Faradaic efficiency of 91% and stability of 750-h (>30 days). When the electrode area is scaled up to 25 cm², 262 g of pure propylene oxide is obtained after 50-h continuous electrolysis at 6.25 A. These findings demonstrate that the electrochemical bromohydrin route represents a viable alternative for the manufacture of epoxides.