NASICON-structured Na3MnTi(PO4)2.83F0.5 cathode with high energy density and rate performance for sodium-ion batteries

Jiefei Liu, Yu Zhao, Xiaofeng Huang, Yu Zhou, Kwok ho Lam, Denis Y.W. Yu, Xianhua Hou

Research output: Journal article publicationJournal articleAcademic researchpeer-review

Abstract

NASICON-structured materials with high ionic conductivity, robust structure, and high operation potential have aroused extensive attentions as cathode for sodium-ion batteries (SIBs). However, the poor intrinsic electronic conductivity and low specific capacity are crucial obstacles for practical application of NASICON materials. Herein, a new NASICON-structured Na3MnTi(PO4)2.83F0.5 (NMTPF-0.5) with the hierarchical and porous structure is synthesized by a simple sol–gel method. The Rietveld refinements and Inductively Coupled Plasma (ICP) chemical analysis confirms the NASICON structure of NMTPF-0.5. The unique structural design significantly enhances rate performance. Meanwhile, the introduction of F- stimulates electrochemical activities of Mn, and stabilizes crystal structure compared with traditional Na3MnTi(PO4)3. Consequently, the NMTPF-0.5 achieves the high energy density of 511 Wh kg−1 at 0.1C, an outstanding rate performance (364 Wh kg−1 at 10C), and the desirable cycling stabilities exceeding 500 cycles at 10C. The ex-situ XRD reveals the insertion/extraction of Na+ through the reversible solid-solution mechanism. Moreover, we statistically analyze how the electrochemical properties and microstructure affected by various F- substitution amounts. This study explored a novel strategy for designing high capacity and high power-density cathode materials for SIBs via the microstructure and crystal structure optimization.

Original languageEnglish
Article number134839
JournalChemical Engineering Journal
Volume435
DOIs
Publication statusPublished - 1 May 2022

Keywords

  • Cathodes
  • Fast kinetics
  • Hierarchical and porous structure
  • High energy
  • Sodium-ion batteries

ASJC Scopus subject areas

  • Chemistry(all)
  • Environmental Chemistry
  • Chemical Engineering(all)
  • Industrial and Manufacturing Engineering

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