Wang Xudong, Chen Jiepeng, Huang Yun, Liu Jiapin, Fu Lei, Liu Li, Zeng Wenping, Xiao Jie, Zhang Xiaoyan, Li Xing, Wang Mingshan, Lin Yuanhua, Cao Haijun
School of New Energy and Materials, Southwest Petroleum University, Chengdu 610500, China.
Energy Storage Research Institute, School of New Energy and Materials, Southwest Petroleum University, Chengdu 610500, China.
ACS Appl Mater Interfaces. 2024 Oct 2. doi: 10.1021/acsami.4c12015.
NaMnV(PO) (NMVP) has gained attention for its high redox potential, good cycling stability, and competitive price but suffers from poor intrinsic electronic conductivity and Jahn-Teller effect from Mn. In this work, cation/anion doping strategy was used for bioderived carbon-coated NMVP (NMVP/AN) to improve the structural stability and electrochemical performance, where Al doping inhibited the dissolution of Mn and enhanced the Mn/Mn redox pair activity; besides, F doping not only weakens the Na-O bond but also endows the hierarchical and porous structure of NMVP/AN, which led to a more rapid and fluid transfer of Na. The elaborately designed NaMnAlV(PO)/AN (NMAVP/AN) exhibits 105.9 mA h g at 0.5 C, and the as-prepared NaMnV(POF)/AN (NMVPF/AN) delivers 104.1 mA h g at 5 C. Further demonstration of the hard carbon//NMAVP/AN full cell manifests the good potential of Al-doped NMVP/AN for practical applications (100.6 mA h g at 1 C). These findings open up the possibility of unlocking the high-performance Na superionic conductor (NASICON).
NaMnV(PO)（NMVP）因其高氧化还原电位、良好的循环稳定性和具有竞争力的价格而受到关注，但存在本征电子导电性差以及Mn的 Jahn-Teller 效应等问题。在这项工作中，采用阳离子/阴离子掺杂策略对生物衍生碳包覆的 NMVP（NMVP/AN）进行处理，以提高其结构稳定性和电化学性能，其中 Al 掺杂抑制了 Mn 的溶解并增强了 Mn/Mn 氧化还原对活性；此外，F 掺杂不仅削弱了 Na-O 键，还赋予了 NMVP/AN 分级多孔结构，这导致 Na 的转移更加快速和流畅。精心设计的 NaMnAlV(PO)/AN（NMAVP/AN）在 0.5 C 时表现出 105.9 mA h g 的比容量，制备的 NaMnV(POF)/AN（NMVPF/AN）在 5 C 时的比容量为 104.1 mA h g。硬碳//NMAVP/AN 全电池的进一步展示表明，Al 掺杂的 NMVP/AN 在实际应用中具有良好的潜力（在 1 C 时为 100.6 mA h g）。这些发现为解锁高性能钠超离子导体（NASICON）开辟了可能性。
