Revisit Electrolyte Chemistry of Hard Carbon in Ether for Na Storage

Jun Pan; Yi-Yang Sun; Yehao Yan; Lei Feng; Yifan Zhang; Aming Lin; Fuqiang Huang; Jian Yang

doi:10.1021/jacsau.1c00158

Revisit Electrolyte Chemistry of Hard Carbon in Ether for Na Storage

JACS Au. 2021 Jul 6;1(8):1208-1216. doi: 10.1021/jacsau.1c00158. eCollection 2021 Aug 23.

Authors

Jun Pan^{1

2}, Yi-Yang Sun¹, Yehao Yan³, Lei Feng², Yifan Zhang¹, Aming Lin¹, Fuqiang Huang^{1

4}, Jian Yang²

Affiliations

¹ State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Science, Shanghai 200050, China.
² Key Laboratory of Colloid and Interface Chemistry Ministry of Education School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China.
³ Department of Public Health, Jining Medical University, Jining 272013, China.
⁴ State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.

Abstract

Hard carbons (HCs) as an anode material in sodium ion batteries present enhanced electrochemical performances in ether-based electrolytes, giving them potential for use in practical applications. However, the underlying mechanism behind the excellent performances is still in question. Here, ex situ nuclear magnetic resonance, gas chromatography-mass spectrometry, and high-resolution transmission electron microscopy were used to clarify the insightful chemistry of ether- and ester-based electrolytes in terms of the solid-electrolyte interphase (SEI) on hard carbons. The results confirm the marked electrolyte decomposition and the formation of a SEI film in EC/DEC but no SEI film in the case of diglyme. In situ electrochemical quartz crystal microbalance and molecular dynamics support that ether molecules have likely been co-intercalated into hard carbons. To our knowledge, these results are reported for the first time. It might be very useful for the rational design of advanced electrode materials based on HCs in the future.