Xie Min, Li Xiaoying, Chen Yufan, Liao Xiangyue, Zheng Qiaoji, Zhang Heng, Lam Kwok-Ho, Lin Dunmin
College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610066, China.
College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610066, China.
J Colloid Interface Sci. 2025 Jul 15;700(Pt 2):138461. doi: 10.1016/j.jcis.2025.138461.
Sodium superionic conductor (NASICON)-type phosphates cathodes have attracted considerable attention due to their high operational voltage and robust three-dimensional (3D) framework; however, the poor intrinsic electronic conductivity and low energy density hinder their broader application. Herein, a novel NASICON-type NaVFeMo(PO) cathode was designed through Fe/Mo dual-doping at the V sites of NaV(PO) and synthesized via a conventional high-temperature solid-state method. The introduction of Fe activates the V/V redox couple at a high voltage plateau (∼ 4.0 V), while also generates additional Fe/Fe and V/V redox pairs. Meanwhile, the doing of Mo creates cation vacancies, effectively modulating the electronic structure of vanadium and promoting ionic transport kinetics. Benefiting from this dual-doping strategy, the NaVFeMo(PO) cathode delivers a high capacity of 123.4 mAh g at 0.2C and an impressive energy density of 406 Wh kg within 2.2-4.2 V. Moreover, it exhibits outstanding cycling stability, presenting a capacity retention of 92 % after 2500 cycles at 30C. This work highlights a viable strategy for advancing high-performance NASICON-type cathodes through complex metal ion doping.
钠超离子导体（NASICON）型磷酸盐阴极因其高工作电压和坚固的三维（3D）框架而备受关注；然而，其固有的电子导电性差和能量密度低阻碍了它们的更广泛应用。在此，通过在NaV(PO)的V位点进行Fe/Mo双掺杂设计了一种新型NASICON型NaVFeMo(PO)阴极，并通过传统的高温固态方法合成。Fe的引入在高压平台（~4.0 V）激活了V/V氧化还原对，同时还产生了额外的Fe/Fe和V/V氧化还原对。同时，Mo的掺杂产生阳离子空位，有效调节钒的电子结构并促进离子传输动力学。受益于这种双掺杂策略，NaVFeMo(PO)阴极在0.2C下具有123.4 mAh g的高容量，在2.2-4.2 V范围内具有406 Wh kg的令人印象深刻的能量密度。此外，它表现出出色的循环稳定性，在30C下2500次循环后容量保持率为92%。这项工作突出了一种通过复杂金属离子掺杂推进高性能NASICON型阴极的可行策略。
