NASICON-structured Na₃MnTi(PO₄)_2.83F_0.5 cathode with high energy density and rate performance for sodium-ion batteries

Liu, J., Zhao, Y., Huang, X., Zhou, Y., Lam, K. H. , Yu, D.Y.W. and Hou, X. (2022) NASICON-structured Na₃MnTi(PO₄)_2.83F_0.5 cathode with high energy density and rate performance for sodium-ion batteries. Chemical Engineering Journal, 435(3), 134839. (doi: 10.1016/j.cej.2022.134839)

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.

• Item Type: Articles
• Additional Information: This work was financially supported by the joint fund project of Guangdong and Guangxi (2020A1515410008), the Science and Technology Program of Guangzhou (No.2019050001), the Science and Technology Program of Guangdong Province (2018B050502010), National Key Research and Development Program of China (2019YFE0198000), the third batch of Zhaoqing Xijiang Talent Innovation Team project (2019).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Lam, Dr Koko
• Authors: Liu, J., Zhao, Y., Huang, X., Zhou, Y., Lam, K. H., Yu, D.Y.W., and Hou, X.
• College/School: College of Science and Engineering > School of Engineering > Systems Power and Energy
• Journal Name: Chemical Engineering Journal
• Publisher: Elsevier
• ISSN: 1385-8947
• ISSN (Online): 1873-3212
• Published Online: 21 January 2022