Highly Reversible Intercalation of Calcium Ions in Layered Vanadium Compounds Enabled by Acetonitrile-Water Hybrid Electrolyte

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

6 Scopus Citations
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Author(s)

  • Xiaolu Qin
  • Xu Zhao
  • Guobin Zhang
  • Linyuan Li
  • Xiaoke Wang
  • Cuiping Han
  • Baohua Li

Detail(s)

Original languageEnglish
Pages (from-to)12040–12051
Journal / PublicationACS Nano
Volume17
Issue number13
Online published20 Jun 2023
Publication statusPublished - 11 Jul 2023

Abstract

Currently, the development of calcium-ion batteries (CIBs) is still in its infancy and greatly plagued by the absence of satisfactory cathode materials and compatible electrolytes. Herein, an acetonitrile-water hybrid electrolyte is first developed in CIB chemistry, in which, the strong lubricating and shielding effect of water solvent significantly boosts the swift transport of bulky Ca2+, thus contributing to large capacity storage of Ca2+ in layered vanadium oxides (Ca0.25V2O5·nH2O, CVO). Meanwhile, the acetonitrile component noticeably suppresses the dissolution of vanadium species during repeated Ca2+-ion uptake/release, endowing the CVO cathode with a robust cycle life. More importantly, spectral characterization and molecular dynamics simulation confirm that the water molecules are well stabilized by the mutual hydrogen bonding with acetonitrile molecules (O-H···N), endowing the aqueous hybrid electrolyte with high electrochemical stability. By using this aqueous hybrid electrolyte, the CVO electrode shows a high specific discharge capacity of 158.2 mAh g-1 at 0.2 A g-1, an appealing capacity of 104.6 mAh g-1 at a high rate of 5 A g-1, and a capacity retention of 95% after 2000 cycles at 1.0 A g-1, which is a record-high performance for CIBs reported so far. A mechanistic study exemplifies the reversible extraction of Ca2+ from the gap of VO polyhedral layers, which are accompanied by the reversible V-O and V-V skeleton change as well as reversible variation of layer spacing. This work constitutes a major advance in developing high-performance Ca-ion batteries. © 2023 American Chemical Society.

Research Area(s)

  • acetonitrile, calcium-ion battery, hybrid electrolyte, multivalent ion battery, vanadium oxides

Citation Format(s)

Highly Reversible Intercalation of Calcium Ions in Layered Vanadium Compounds Enabled by Acetonitrile-Water Hybrid Electrolyte. / Qin, Xiaolu; Zhao, Xu; Zhang, Guobin et al.
In: ACS Nano, Vol. 17, No. 13, 11.07.2023, p. 12040–12051.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review