Boosting multielectron reaction stability of sodium vanadium phosphate by high-entropy substitution

Zhiqiang Hao, Xiaoyan Shi, Wenqing Zhu, Zhuo Yang, Xunzhu Zhou, Chenchen Wang, Lin Li*, Weibo Hua, Chang-Qi Ma, Shulei Chou*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

Na3V2(PO4)3 (NVP) based on the multielectron reactions between V2+ and V5+ has been considered a promising cathode for sodium-ion batteries (SIBs). However, it still suffers from unsatisfactory stability, caused by the poor reversibility of the V5+/V4+ redox couple and structure evolution. Herein, we propos a strategy that combines high-entropy substitution and electrolyte optimization to boost the reversible multielectron reactions of NVP. The high reversibility of the V5+/V4+ redox couple and crystalline structure evolution are disclosed by in situ X-ray absorption near-edge structure spectra and in situ X-ray diffraction. Meanwhile, the electrochemical reaction kinetics of high-entropy substitution NVP (HE-NVP) can be further improved in the diglyme-based electrolyte. These enable HE-NVP to deliver a superior electrochemical performance (capacity retention of 93.1% after 2000 cycles; a large reversible capacity of 120 mAh g–1 even at 5.0 A g–1). Besides, the long cycle life and high power density of the HE-NVP∥natural graphite full-cell configuration demonstrated the superiority of HE-NVP cathode in SIBs. This work highlights that the synergism of high-entropy substitution and electrolyte optimization is a powerful strategy to enhance the sodium-storage performance of polyanionic cathodes for SIBs.
Original languageEnglish
Number of pages11
JournalACS Nano
Early online date22 Mar 2024
DOIs
Publication statusE-pub ahead of print - 22 Mar 2024

Keywords

  • Sodium-ion batteries
  • Sodium vanadium phosphate
  • High-entropy substitution
  • Multi electron reactions
  • Sodium-storage mechanism

Fingerprint

Dive into the research topics of 'Boosting multielectron reaction stability of sodium vanadium phosphate by high-entropy substitution'. Together they form a unique fingerprint.

Cite this