Understanding the sulphur-oxygen exchange process of metal sulphides prior to oxygen evolution reaction

Yang Hu; Yao Zheng; Jing Jin; Yantao Wang; Yong Peng; Jie Yin; Wei Shen; Yichao Hou; Liu Zhu; Li An; Min Lu; Pinxian Xi; Chun-Hua Yan

doi:10.1038/s41467-023-37751-y

Understanding the sulphur-oxygen exchange process of metal sulphides prior to oxygen evolution reaction

Nat Commun. 2023 Apr 7;14(1):1949. doi: 10.1038/s41467-023-37751-y.

Authors

Yang Hu^#^{1

2}, Yao Zheng^#³, Jing Jin^#¹, Yantao Wang¹, Yong Peng^{4

5}, Jie Yin^{1

2}, Wei Shen¹, Yichao Hou¹, Liu Zhu^{6

7}, Li An^{1

2}, Min Lu^{1

2}, Pinxian Xi^{8

9}, Chun-Hua Yan^{1

2

10}

Affiliations

¹ State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China.
² Frontiers Science Center for Rare Isotopes, Lanzhou University, Lanzhou, 730000, China.
³ School of Chemical Engineering and Advanced Materials, The University of Adelaide, Adelaide, SA, 5005, Australia.
⁴ School of Materials and Energy, Lanzhou University, Lanzhou, 730000, China. [email protected].
⁵ Electron Microscopy Centre, Lanzhou University, Lanzhou, 730000, China. [email protected].
⁶ School of Materials and Energy, Lanzhou University, Lanzhou, 730000, China.
⁷ Electron Microscopy Centre, Lanzhou University, Lanzhou, 730000, China.
⁸ State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China. [email protected].
⁹ Frontiers Science Center for Rare Isotopes, Lanzhou University, Lanzhou, 730000, China. [email protected].
¹⁰ Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, PKU-HKU Joint Laboratory in Rare Earth Materials and Bioinorganic Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.

^# Contributed equally.

Abstract

Dynamic reconstruction of metal sulphides during electrocatalytic oxygen evolution reaction (OER) has hampered the acquisition of legible evidence for comprehensively understanding the phase-transition mechanism and electrocatalytic activity origin. Herein, modelling on a series of cobalt-nickel bimetallic sulphides, we for the first time establish an explicit and comprehensive picture of their dynamic phase evaluation pathway at the pre-catalytic stage before OER process. By utilizing the in-situ electrochemical transmission electron microscopy and electron energy loss spectroscopy, the lattice sulphur atoms of (NiCo)S_1.33 particles are revealed to be partially substituted by oxygen from electrolyte to form a lattice oxygen-sulphur coexisting shell surface before the generation of reconstituted active species. Such S-O exchange process is benefitted from the subtle modulation of metal-sulphur coordination form caused by the specific Ni and Co occupation. This unique oxygen-substitution behaviour produces an (NiCo)O_xS_1.33-x surface to reduce the energy barrier of surface reconstruction for converting sulphides into active oxy/hydroxide derivative, therefore significantly increasing the proportion of lattice oxygen-mediated mechanism compared to the pure sulphide surface. We anticipate this direct observation can provide an explicit picture of catalysts' structural and compositional evolution during the electrocatalytic process.

Abstract

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