First-principles calculations indicate that Mn_0.5Ti₂(PO₄)₃ is more suited to potassium-ion storage because of its lower energy gap than that of KTi₂(PO₄)₃. A flexible Mn_0.5Ti₂(PO₄)₃/C nanofiber film (F-MTP/C NFF) has been first synthesized via electrospinning and applied to potassium-ion batteries as a self-standing anode. An integral carbon conductive network, unique one-dimensional nanostructure, and exceptional mechanical flexibility give F-MTP/C NFF outstanding potassium-ion storage performance. Impressively, the self-standing F-MTP/C NFF electrode delivers a high specific capacity of 218 mA h g⁻¹ at 0.02 A g⁻¹ and shows ultra-long cycling stability of 2000 cycles at 1 A g⁻¹. This work may give a new insight into developing NASICON-type Ti-based materials as flexible electrodes for potassium-ion batteries.

中文翻译：

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用于钾离子电池的具有优异循环稳定性的柔性Mn0.5Ti2(PO4)3/C纳米纤维薄膜

第一性原理计算表明，Mn _0.5 Ti ₂ (PO ₄ ) ₃比KTi ₂ (PO ₄ ) ₃能隙低，因此更适合于钾离子存储。柔性 Mn _0.5 Ti ₂ (PO ₄ ) ₃ /C 纳米纤维薄膜 (F-MTP/C NFF) 已首次通过以下方法合成静电纺丝并作为自立式阳极应用于钾离子电池。完整的碳导电网络、独特的一维纳米结构和卓越的机械柔韧性赋予 F-MTP/C NFF 出色的钾离子存储性能。令人印象深刻的是，自立式 F-MTP/C NFF 电极在 0.02 A g ^{-1 下}可提供 218 mA hg ^-1的高比容量，并在 1 A g ^{-1 下}显示出 2000 次循环的超长循环稳定性。这项工作可能为开发 NASICON 型钛基材料作为钾离子电池的柔性电极提供新的见解。