Scholarlink

<p>Na<sub>3</sub>V<sub>2</sub>(PO<sub>4</sub>)<sub>3</sub> (NVP) is considered the most promising cathode material for sodium-ion batteries due to its unique ion transport channel, but the toxicity and price of elemental V is forcing the search for new cathode materials. Na<sub>4</sub>VMn(PO<sub>4</sub>)<sub>3</sub>(NVMP) has the same sodium superionic conductor (NASICON) structure as NVP, and it has higher voltage and energy density, but the Jahn–Teller effect of Mn<sup>3+</sup>, the dissolution of transition metals, and the poor conductivity severely limit its application. In this work, a simple two-step method was used to prepare amorphous Al<sub>2</sub>O<sub>3</sub> and Al<sup>3+</sup> doped double-acting NVMP, which not only suppressed the Jahn–Teller effect but also effectively improved structural stability. Among them, our prepared Na<sub>4</sub>VMn(PO<sub>4</sub>)<sub>3</sub> (NVMP-0.5%Al) with 0.5% amorphous Al<sub>2</sub>O<sub>3</sub> coating still has a specific capacity of 58.7 mAh g<sup>−1</sup> with 67.9% capacity retention after 1000 cycles at 5 C current density, and at current densities of 0.2, 0.5, 1, 2, 5, 10, 15, and 20 C showed reversible capacities of 97.7, 89.1, 84.2, 82.5, 76.1, 70.0, 66.9, and 62.9 mAh g<sup>−1</sup>, respectively. This work significantly improves the cycle stability and rate performance of NVMP and effectively solves the problems of NVMP, which will be beneficial to the practical application of NVMP.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Enhanced cycling and rate performance of Al-doped and amorphous Al2O3 coating Na4VMn(PO4)3 prepared through facile two-step synthesis

  • 期刊论文

  • 发表日期：

    2025年9月16日

查看全文
  • Xuan-Xi Liu,
  • Zu-Tao Pan,
  • Yao Xu,
  • Kun Yan,
  • Qi Zhou,
  • Ling-Bin Kong

摘要

Na3V2(PO4)3 (NVP) is considered the most promising cathode material for sodium-ion batteries due to its unique ion transport channel, but the toxicity and price of elemental V is forcing the search for new cathode materials. Na4VMn(PO4)3(NVMP) has the same sodium superionic conductor (NASICON) structure as NVP, and it has higher voltage and energy density, but the Jahn–Teller effect of Mn3+, the dissolution of transition metals, and the poor conductivity severely limit its application. In this work, a simple two-step method was used to prepare amorphous Al2O3 and Al3+ doped double-acting NVMP, which not only suppressed the Jahn–Teller effect but also effectively improved structural stability. Among them, our prepared Na4VMn(PO4)3 (NVMP-0.5%Al) with 0.5% amorphous Al2O3 coating still has a specific capacity of 58.7 mAh g−1 with 67.9% capacity retention after 1000 cycles at 5 C current density, and at current densities of 0.2, 0.5, 1, 2, 5, 10, 15, and 20 C showed reversible capacities of 97.7, 89.1, 84.2, 82.5, 76.1, 70.0, 66.9, and 62.9 mAh g−1, respectively. This work significantly improves the cycle stability and rate performance of NVMP and effectively solves the problems of NVMP, which will be beneficial to the practical application of NVMP.