In Situ Atomic-Scale Deciphering of Multiple Dynamic Phase Transformations and Reversible Sodium Storage in Ternary Metal Sulfide Anode

Ruining Fu; Jianhai Pan; Mingyuan Wang; Huihua Min; Hanghang Dong; Ran Cai; Zhefei Sun; Yuwei Xiong; Fuhan Cui; Shuang-Ying Lei; Shuangqiang Chen; Jing Chen; Litao Sun; Qiaobao Zhang; Feng Xu

doi:10.1021/acsnano.3c02138

In Situ Atomic-Scale Deciphering of Multiple Dynamic Phase Transformations and Reversible Sodium Storage in Ternary Metal Sulfide Anode

ACS Nano. 2023 Jul 11;17(13):12483-12498. doi: 10.1021/acsnano.3c02138. Epub 2023 Jun 16.

Authors

Ruining Fu¹, Jianhai Pan², Mingyuan Wang¹, Huihua Min³, Hanghang Dong⁴, Ran Cai⁵, Zhefei Sun², Yuwei Xiong¹, Fuhan Cui¹, Shuang-Ying Lei¹, Shuangqiang Chen⁴, Jing Chen¹, Litao Sun¹, Qiaobao Zhang², Feng Xu¹

Affiliations

¹ SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of the Ministry of Education, Southeast University, Nanjing 210096, People's Republic of China.
² State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Materials, Xiamen University, Xiamen, Fujian 361005, People's Republic of China.
³ Electron Microscope Laboratory, Nanjing Forestry University, Nanjing 210037, People's Republic of China.
⁴ Department of Chemical Engineering, School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, People's Republic of China.
⁵ Beijing Advanced Innovation Center for Intelligent Robots and Systems, School of Medical Technology, Beijing Institute of Technology, Beijing 100081, People's Republic of China.

PMID: 37326660
DOI: 10.1021/acsnano.3c02138

Abstract

Ternary metal sulfides (TMSs), endowed with the synergistic effect of their respective binary counterparts, hold great promise as anode candidates for boosting sodium storage performance. Their fundamental sodium storage mechanisms associated with dynamic structural evolution and reaction kinetics, however, have not been fully comprehended. To enhance the electrochemical performance of TMS anodes in sodium-ion batteries (SIBs), it is of critical importance to gain a better mechanistic understanding of their dynamic electrochemical processes during live (de)sodiation cycling. Herein, taking BiSbS₃ anode as a representative paradigm, its real-time sodium storage mechanisms down to the atomic scale during the (de)sodiation cycling are systematically elucidated through in situ transmission electron microscopy. Previously unexplored multiple phase transformations involving intercalation, two-step conversion, and two-step alloying reactions are explicitly revealed during sodiation, in which newly formed Na₂BiSbS₄ and Na₂BiSb are respectively identified as intermediate phases of the conversion and alloying reactions. Impressively, the final sodiation products of Na₆BiSb and Na₂S can recover to the original BiSbS₃ phase upon desodiation, and afterward, a reversible phase transformation can be established between BiSbS₃ and Na₆BiSb, where the BiSb as an individual phase (rather than respective Bi and Sb phases) participates in reactions. These findings are further verified by operando X-ray diffraction, density functional theory calculations, and electrochemical tests. Our work provides valuable insights into the mechanistic understanding of sodium storage mechanisms in TMS anodes and important implications for their performance optimization toward high-performance SIBs.

Keywords: electrochemical performance; in situ transmission electron microscopy (TEM); phase transformations; sodium storage mechanisms; ternary metal sulfide anodes.