Issue

Vol. 18 (2026)

Iron–Manganese Dual-Doping Tailors the Electronic Structure of Na3V2(PO4)2F3 for High-Performance Sodium-Ion Batteries

https://doi.org/10.1007/s40820-025-01881-3
Jien Li
Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hung Hom, Hong Kong 999077, People’s Republic of China
Shuang Luo
Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong 999077, People’s Republic of China
Renjie Li
Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hung Hom, Hong Kong 999077, People’s Republic of China
Yingkai Hua
Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hung Hom, Hong Kong 999077, People’s Republic of China
Linlong Lyu
Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hung Hom, Hong Kong 999077, People’s Republic of China
Xiangjun Pu
Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hung Hom, Hong Kong 999077, People’s Republic of China
Jun Fan
Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong 999077, People’s Republic of China
Zheng‑Long Xu
Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hung Hom, Hong Kong 999077, People’s Republic of China

Corresponding Author: Zheng‑Long Xu

zhenglong.xu@polyu.edu.hk

Nano-Micro Letters, Vol. 18 (2026), Article Number: 176

Abstract

Sodium superionic conductor (NASICON)-type materials are promising cathodes for sodium-ion batteries due to their stable multi-channel frameworks and exceptional ionic conductivity. Among them, Na3V2(PO4)2F3 (NVPF) has attracted significant attention. However, the low electronic conductivity and phase impurities limit its sodium storage capability. Herein, we present a Fe and Mn dual-doped NVPF (FM-NVPF) cathode with improved phase purity, electronic conductivity, and electrochemical activities. Detailed ex-situ analyses and density functional theory calculations reveal that Fe and Mn dopants induce defect energy levels and modulate the electronic structure, resulting in a direct-to-indirect bandgap transition in NVPF, which in turn increases carrier concentration and lifetime, accelerates ionic/electronic transport, and improves structural stability. As a result, the FM-NVPF cathode delivers a high capacity of 126.6 mAh g⁻1 at 0.1 C (1 C = 128 mAh g⁻1) and outstanding high-rate capability of 67.6 mAh g⁻1 at 50 C, corresponding to 1.2 min per charge. Furthermore, Na ion full cells assembled with the FM-NVPF cathodes and hard carbon anodes exhibit a high energy density of about 175 Wh kg−1cathode+anode mass and appealing cyclic stability. This work provides an efficient strategy for developing high-purity and high-performance NVPF cathode materials for advanced sodium-ion batteries.


Highlights:
1 Regulation of the electronic structure of Na3V2(PO4)2F3 (NVPF) via iron–manganese dual-doping enhances electrical conductivity and ion diffusion kinetics.
2 Efficient charge transport and highly reversible Na+ de/intercalation in Fe-Mn dual-doped NVPF (FM-NVPF) enable exceptional rate capability and charge storage capacity.
3 The full cell with the FM-NVPF cathode and hard carbon anode displays superior rate performance and cycling stability.

Keywords

Sodium-ion batteries Sodium fluorophosphates Electronic structure Fe–Mn co-doping
Li, Jien, Shuang Luo, Renjie Li, Yingkai Hua, Linlong Lyu, Xiangjun Pu, Jun Fan, and Zheng‑Long Xu. 2026. “Iron–Manganese Dual-Doping Tailors the Electronic Structure of Na3V2(PO4)2F3 for High-Performance Sodium-Ion Batteries”. Nano-Micro Letters 18 (January):176. https://doi.org/10.1007/s40820-025-01881-3.
Download Citation
Endnote/Zotero/Mendeley (RIS)
BibTeX
References
  1. H. Huang, X. Wu, Y. Gao, Z. Li, W. Wang et al., Polyanionic cathode materials: a comparison between Na-ion and K-ion batteries. Adv. Energy Mater. 14(14), 2304251 (2024). https://doi.org/10.1002/aenm.202304251
  2. Y. Gao, H. Zhang, J. Peng, L. Li, Y. Xiao et al., A 30-years overview of sodium-ion batteries. Carbon Energy 6(6), e464 (2024). https://doi.org/10.1002/cey2.464
  3. E. Goikolea, V. Palomares, S. Wang, I.R. de Larramendi, X. Guo et al., Na-ion batteries: approaching old and new challenges. Adv. Energy Mater. 10(44), 2002055 (2020). https://doi.org/10.1002/aenm.202002055
  4. M. He, S. Liu, J. Wu, J. Zhu, Review of cathode materials for sodium-ion batteries. Prog. Solid State Chem. 74, 100452 (2024). https://doi.org/10.1016/j.progsolidstchem.2024.100452
  5. E. Gabriel, C. Ma, K. Graff, A. Conrado, D. Hou et al., Heterostructure engineering in electrode materials for sodium-ion batteries: recent progress and perspectives. Escience 3(5), 100139 (2023). https://doi.org/10.1016/j.esci.2023.100139
  6. B. Peng, G. Wan, N. Ahmad, L. Yu, X. Ma et al., Recent progress in the emerging modification strategies for layered oxide cathodes toward practicable sodium ion batteries. Adv. Energy Mater. 13(27), 2370117 (2023). https://doi.org/10.1002/aenm.202370117
  7. M.T. Ahsan, Z. Ali, M. Usman, Y. Hou, Unfolding the structural features of NASICON materials for sodium-ion full cells. Carbon Energy 4(5), 776–819 (2022). https://doi.org/10.1002/cey2.222
  8. Q. Zhou, L. Wang, W. Li, K. Zhao, M. Liu et al., Sodium superionic conductors (NASICONs) as cathode materials for sodium-ion batteries. Electrochem. Energy Rev. 4(4), 793–823 (2021). https://doi.org/10.1007/s41918-021-00120-8
  9. R. Thirupathi, V. Kumari, S. Chakrabarty, S. Omar, Recent progress and prospects of NASICON framework electrodes for Na-ion batteries. Prog. Mater. Sci. 137, 101128 (2023). https://doi.org/10.1016/j.pmatsci.2023.101128
  10. H. Xu, Q. Yan, W. Yao, C.-S. Lee, Y. Tang, Mainstream optimization strategies for cathode materials of sodium-ion batteries. Small Struct. 3(4), 2100217 (2022). https://doi.org/10.1002/sstr.202100217
  11. K. Liang, H. Zhao, J. Li, X. Huang, S. Jia et al., Engineering crystal growth and surface modification of Na3V2(PO4)2F3 cathode for high-energy-density sodium-ion batteries. Small 19(19), 2207562 (2023). https://doi.org/10.1002/smll.202207562
  12. X. Wang, C. Niu, J. Meng, P. Hu, X. Xu et al., Novel K3V2(PO4)3/C bundled nanowires as superior sodium-ion battery electrode with ultrahigh cycling stability. Adv. Energy Mater. 5(17), 1500716 (2015). https://doi.org/10.1002/aenm.201500716
  13. Z.-Y. Gu, J.-Z. Guo, J.-M. Cao, X.-T. Wang, X.-X. Zhao et al., An advanced high-entropy fluorophosphate cathode for sodium-ion batteries with increased working voltage and energy density. Adv. Mater. 34(14), 2110108 (2022). https://doi.org/10.1002/adma.202110108
  14. J.Y. Park, Y. Shim, Y.-I. Kim, Y. Choi, H.J. Lee et al., An iron-doped NASICON type sodium ion battery cathode for enhanced sodium storage performance and its full cell applications. J. Mater. Chem. A 8(39), 20436–20445 (2020). https://doi.org/10.1039/D0TA07766F
  15. L. Li, Y. Xu, R. Chang, C. Wang, S. He et al., Unraveling the mechanism of optimal concentration for Fe substitution in Na3V2(PO4)2F3/C for sodium-ion batteries. Energy Storage Mater. 37, 325–335 (2021). https://doi.org/10.1016/j.ensm.2021.01.029
  16. Y. Zhang, S. Guo, H. Xu, Synthesis of uniform hierarchical Na3V1.95Mn0.05(PO4)2F3@C hollow microspheres as a cathode material for sodiumion batteries. J Mater Chem A. 6, 4525–4534 (2018). https://doi.org/10.1039/C7TA11105C
  17. L. Zhu, M. Wang, S. Xiang, D. Sun, Y. Tang et al., A medium-entropy phosphate cathode with multielectron redox reaction for advanced sodium-ion batteries. Adv. Energy Mater. 13(36), 2302046 (2023). https://doi.org/10.1002/aenm.202302046
  18. Z. Wang, G. Cui, Q. Zheng, X. Ren, Q. Yang et al., Ultrafast charge-discharge capable and long-life Na3.9Mn0.95Zr0.05V(PO4)3/C cathode material for advanced sodium-ion batteries. Small 19(17), 2206987 (2023). https://doi.org/10.1002/smll.202206987
  19. Y. Subramanian, W. Oh, W. Choi, H. Lee, M. Jeong et al., Optimizing high voltage Na3V2(PO4)2F3 cathode for achieving high rate sodium-ion batteries with long cycle life. Chem. Eng. J. 403, 126291 (2021). https://doi.org/10.1016/j.cej.2020.126291
  20. P.E. Blöchl, Projector augmented-wave method. Phys. Rev. B 50(24), 17953–17979 (1994). https://doi.org/10.1103/physrevb.50.17953
  21. G. Kresse, J. Furthmüller, Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys. Rev. B 54(16), 11169–11186 (1996). https://doi.org/10.1103/physrevb.54.11169
  22. S. Grimme, Semiempirical GGA-type density functional constructed with a long-range dispersion correction. J. Comput. Chem. 27(15), 1787–1799 (2006). https://doi.org/10.1002/jcc.20495
  23. S. Grimme, S. Ehrlich, L. Goerigk, Effect of the damping function in dispersion corrected density functional theory. J. Comput. Chem. 32(7), 1456–1465 (2011). https://doi.org/10.1002/jcc.21759
  24. J. Wang, H. Jing, X. Wang, Y. Xue, Q. Liang et al., Electrostatically shielded transportation enabling accelerated Na+ diffusivity in high-performance fluorophosphate cathode for sodium-ion batteries. Adv. Funct. Mater. 34(24), 2315318 (2024). https://doi.org/10.1002/adfm.202315318
  25. K. Burke, Perspective on density functional theory. J. Chem. Phys. 136(15), 150901 (2012). https://doi.org/10.1063/1.4704546
  26. L. Deng, F.-D. Yu, Y. Xia, Y.-S. Jiang, X.-L. Sui et al., Stabilizing fluorine to achieve high-voltage and ultra-stable Na3V2(PO4)2F3 cathode for sodium ion batteries. Nano Energy 82, 105659 (2021). https://doi.org/10.1016/j.nanoen.2020.105659
  27. L. Li, J. Zhao, H. Zhao, Y. Qin, X. Zhu et al., Structure, composition and electrochemical performance analysis of fluorophosphates from different synthetic methods: is really Na3V2(PO4)2F3 synthesized? J. Mater. Chem. A 10(16), 8877–8886 (2022). https://doi.org/10.1039/D2TA00565D
  28. H. Yu, H. Jing, Y. Gao, X. Wang, Z.-Y. Gu et al., Unlocking the sodium storage potential in fluorophosphate cathodes: electrostatic interaction lowering versus structural disordering. Adv. Mater. 37(24), 2400229 (2025). https://doi.org/10.1002/adma.202400229
  29. R. Su, W. Zhu, K. Liang, P. Wei, J. Li et al., Mnx+ substitution to improve Na3V2(PO4)2F3-based electrodes for sodium-ion battery cathode. Molecules 28(3), 1409 (2023). https://doi.org/10.3390/molecules28031409
  30. X. Ou, X. Liang, C. Yang, H. Dai, F. Zheng et al., Mn doped NaV3(PO4)3/C anode with high-rate and long cycle-life for sodium ion batteries. Energy Storage Mater. 12, 153–160 (2018). https://doi.org/10.1016/j.ensm.2017.12.007
  31. H. Li, Y. Wang, X. Zhao, J. Jin, Q. Shen et al., A multielectron-reaction and low-strain Na3.5Fe0.5VCr0.5(PO4)3 cathode for Na-ion batteries. ACS Energy Lett. 8(9), 3666–3675 (2023). https://doi.org/10.1021/acsenergylett.3c01183
  32. C. Xu, J. Zhao, E. Wang, X. Liu, X. Shen et al., A novel NASICON-typed Na4VMn0.5Fe0.5(PO4)3 cathode for high-performance Na-ion batteries. Adv. Energy Mater. 11(22), 2100729 (2021). https://doi.org/10.1002/aenm.202100729
  33. K. Liang, S. Wang, H. Zhao, X. Huang, Y. Ren et al., A facile strategy for developing uniform hierarchical Na3V2(PO4)2F3@carbonized polyacrylonitrile multi-clustered hollow microspheres for high-energy-density sodium-ion batteries. Chem. Eng. J. 428, 131780 (2022). https://doi.org/10.1016/j.cej.2021.131780
  34. Y. Zhang, T. Wang, Y. Tang, Y. Huang, D. Jia et al., In situ redox reaction induced firmly anchoring of Na3V2(PO4)2F3 on reduced graphene oxide and carbon nanosheets as cathodes for high stable sodium-ion batteries. J. Power. Sources 516, 230515 (2021). https://doi.org/10.1016/j.jpowsour.2021.230515
  35. H. Tan, J. Verbeeck, A. Abakumov, G. Van Tendeloo, Oxidation state and chemical shift investigation in transition metal oxides by EELS. Ultramicroscopy 116, 24–33 (2012). https://doi.org/10.1016/j.ultramic.2012.03.002
  36. X. Chen, Q. Wu, P. Guo, X. Liu, Rational design of two dimensional single crystalline Na3V2(PO4)2F3 nanosheets for boosting Na+ migration and mitigating grain pulverization. Chem. Eng. J. 439, 135533 (2022). https://doi.org/10.1016/j.cej.2022.135533
  37. L. Wang, J. Wang, H. Chen, H. Dong, H. Wang et al., Fast screening suitable doping transition metals to Na3V2(PO4)2F3 for sodium-ion batteries with high energy density in wide-temperature range. Adv. Mater. 37, 2505093 (2025). https://doi.org/10.1002/adma.202505093
  38. M. Sun, Y. Sun, H. Ma, S. Wang, Q. Liu et al., High-entropy doping enabling ultrahigh power density for advanced sodium-ion batteries. ACS Nano 19(19), 18386–18396 (2025). https://doi.org/10.1021/acsnano.5c01312
  39. Y. Zhou, G. Xu, J. Lin, Y. Zhang, G. Fang et al., Reversible multielectron redox chemistry in a NASICON-type cathode toward high-energy-density and long-life sodium-ion full batteries. Adv. Mater. 35(44), 2304428 (2023). https://doi.org/10.1002/adma.202304428
  40. J. Zhang, Y. Lai, P. Li, Y. Wang, F. Zhong et al., Boosting rate and cycling performance of K-doped Na3V2(PO4)2F3 cathode for high-energy-density sodium-ion batteries. Green Energy Environ. 7(6), 1253–1262 (2022). https://doi.org/10.1016/j.gee.2021.01.001
  41. A.R. Iarchuk, D.V. Sheptyakov, A.M. Abakumov, Hydrothermal microwave-assisted synthesis of Na3+xV2–yMny(PO4)2F3 solid solutions as potential positive electrodes for Na-ion batteries. ACS Appl. Energy Mater. 4(5), 5007–5014 (2021). https://doi.org/10.1021/acsaem.1c00579
  42. Z.-Y. Gu, J.-Z. Guo, X.-X. Zhao, X.-T. Wang, D. Xie et al., High-ionicity fluorophosphate lattice via aliovalent substitution as advanced cathode materials in sodium-ion batteries. InfoMat 3(6), 694–704 (2021). https://doi.org/10.1002/inf2.12184
  43. N. Huang, Y. Sun, S. Liu, X. Wang, J. Zhang et al., Microwave-assisted rational designed CNT-Mn3 O4)/CoWO4 hybrid nanocomposites for high performance battery-supercapacitor hybrid device. Small 19(35), e2300696 (2023). https://doi.org/10.1002/smll.202300696
  44. G. Li, Y. Su, S. Zhou, J. Shen, D. Liu et al., From 0D to 3D: Controllable synthesis of ammonium vanadate materials for Zn2+ storage with superior rate performance and cycling stability. Chem. Eng. J. 469, 143816 (2023). https://doi.org/10.1016/j.cej.2023.143816
  45. Z.-F. Wu, P.-F. Gao, L. Guo, J. Kang, D.-Q. Fang et al., Robust indirect band gap and anisotropy of optical absorption in B-doped phosphorene. Phys. Chem. Chem. Phys. 19(47), 31796–31803 (2017). https://doi.org/10.1039/C7CP05404A
  46. A. Chaves, J.G. Azadani, H. Alsalman, D.R. da Costa, R. Frisenda et al., Bandgap engineering of two-dimensional semiconductor materials. NPJ 2D Mater Appl. 4, 29 (2020). https://doi.org/10.1038/s41699-020-00162-4
  47. S. Zhang, G. Wang, J. Jin, L. Zhang, Z. Wen et al., Robust and conductive red MoSe2 for stable and fast lithium storage. ACS Nano 12(4), 4010–4018 (2018). https://doi.org/10.1021/acsnano.8b01703
  48. Y. Zhang, L. Tao, C. Xie, D. Wang, Y. Zou et al., Defect engineering on electrode materials for rechargeable batteries. Adv. Mater. 32(7), 1905923 (2020). https://doi.org/10.1002/adma.201905923
  49. D. Zhu, Q. Zhou, Nitrogen doped g-C3N4 with the extremely narrow band gap for excellent photocatalytic activities under visible light. Appl. Catal. B Environ. 281, 119474 (2021). https://doi.org/10.1016/j.apcatb.2020.119474
  50. J. Zhang, F. Shi, J. Lin, D. Chen, J. Gao et al., Self-assembled 3-D architectures of BiOBr as a visible light-driven photocatalyst. Chem. Mater. 20(9), 2937–2941 (2008). https://doi.org/10.1021/cm7031898
  51. M. Li, C. Sun, Q. Ni, Z. Sun, Y. Liu et al., High entropy enabling the reversible redox reaction of V4+/V5+ couple in NASICON-type sodium ion cathode. Adv. Energy Mater. 13(12), 2203971 (2023). https://doi.org/10.1002/aenm.202203971
Read More
Author biographies are not available.
Download this PDF file
PDF SUPPLEMENTARY FILE

Most read articles by the same author(s)