Modulation of Redox Chemistry of Na2Mn3O7by Selective Boron Doping Prompted by Na Vacancies

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review

6 Scopus Citations
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Author(s)

  • Jing Wan
  • Yuegang Qiu
  • Xueping Sun
  • Mingyang Ou
  • Jia Xu
  • Xiaoyu Zhang
  • Yi Liu
  • Shixiong Sun
  • Yue Xu
  • Chun Fang
  • Li Huang
  • Jiantao Han

Detail(s)

Original languageEnglish
Pages (from-to)38769–38777
Journal / PublicationACS Applied Materials and Interfaces
Volume14
Issue number34
Online published17 Aug 2022
Publication statusPublished - 31 Aug 2022

Abstract

The small energy density and chemomechanical degradation of layered manganese oxide limit practical application to sodium-ion batteries (SIBs). Typically, Na2Mn3O7 shows a low redox plateau at 2.1 V versus Na/Na+, and the oxygen redox reaction at a high voltage causes structural collapse. Herein, a Na vacancy-induced boron doping strategy is demonstrated to improve the properties. Boron is incorporated into selective sites in the lattice in the center of the MnO6 octahedral ring at the O-layer. Bonding of boron in the TM layer enhances the electrochemical activity of low-valence Mn, giving rise to two reversible redox peaks at 2.45 and 2.55 V to enhance the average redox voltage. At the same time, the O 2p chemical state becomes weaker around the Fermi level, thus suppressing oxygen overoxidation for the high charge state and strengthening the layered structure during the redox reactions. The reduced Mn-O covalency and small diffusion barrier energy stemming from bonding of boron in the oxygen layer produce excellent rate characteristics. Modulation of the Mn 3d and O 2p orbital in Na2Mn3O7 by Na vacancies leads to selective doping of boron at different sites, and our results reveal that it is an important strategy for studying transition-metal-oxide-layered electrode materials.

Research Area(s)

  • sodium-ion batteries, layered materials, Na2Mn3O7, boron doping, vacancies, CATHODE MATERIALS, VOLTAGE HYSTERESIS, OXIDE CATHODES, ANIONIC REDOX, LITHIUM

Citation Format(s)

Modulation of Redox Chemistry of Na2Mn3O7by Selective Boron Doping Prompted by Na Vacancies. / Wan, Jing; Qiu, Yuegang; Sun, Xueping et al.
In: ACS Applied Materials and Interfaces, Vol. 14, No. 34, 31.08.2022, p. 38769–38777.

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review