A Micro-Nano Flower-Like Na3V2(PO4)3@C Constructed by Polar-Driven H-Bond Engineering Toward High-Rate Sodium Storage

en The polyanionic compound Na 3 V 2 (PO 4 ) 3 (NVP) has emerged as a competitive cathode material for sodium-ion batteries (SIBs), owing to its high-voltage redox activity (3.4 V vs. the Na + /Na reference couple) and NASICON-type framework that enables superior ionic conductivity. However, the electrochemical performance of NVP is hampered by low intrinsic electronic conductivity, particularly under ultra-fast charging and long-term cycling conditions. Herein, a hierarchical micro-nano flower-like Na 3 V 2 (PO 4 ) 3 with a carbon-coating layer (HF-NVP@C) is synthesized by a facile n-propanol-assisted precipitation method. Theoretical analysis and experimental tests reveal that the polar-driven hydrogen bond engineering, manifested in the distinct molecular interaction between n-propanol and ultrapure water (characterized by a shorter O-H bond length of 1.859 Å and higher binding energy of −0.312 eV compared to methanol and ethanol counterparts), underpins the formation of the unique hierarchical micro-nano flower-like architecture. This hierarchical architecture creates an expanded interfacial area, enhances ionic transport pathways, and increases electrochemically active sites. Furthermore, a glucose-derived carbon coating (∼2 nm in thickness) uniformly adheres to the NVP surface, effectively enhancing its electronic conductivity. Thus, the constructed HF-NVP@C exhibits superior rate capability (68.1 mAh g −1 at 150C) and long-term cycling stability (58.7% capacity retention after 5000 cycles at 1C). This work proposes a viable strategy for designing high-performance polyanionic cathodes using hydrogen bond engineering. 摘要 zh 聚阴离子化合物Na 3 V 2 (PO 4 ) 3 @C(NVP)因其具有高电压氧化还原活性(相对于Na + /Na参比电对为3.4 V)以及能实现优异离子电导率的NASICON型骨架结构,已成为一种具有竞争力的钠离子电池(SIBs)正极材料。然而,由于NVP的本征电子电导率较低,导致其在超快充电和长期循环条件下的电化学性能较差。在本文中,通过一种简便的正丙醇辅助沉淀法合成了具有碳包覆层的分级微-纳花状Na 3 V 2 (PO 4 ) 3 @C(HF-NVP@C)。理论分析和实验测试表明,极性驱动的氢键工程体现在正丙醇与超纯水之间独特的分子相互作用上(其O-H键长为1.859 Å,比甲醇和乙醇对应的键长更短,结合能更高-0.312 eV),是形成这种独特分级微-纳花状结构的基础。这种分级结构扩大了活性材料的面积,增强其离子传输通道,并增加电化学活性位点。此外,葡萄糖衍生的碳涂层(约2 nm厚)均匀地附着在NVP表面,有效提高其电子电导率。因此,构建的HF-NVP@C展现出优异的倍率性能(150C下为68.1 mAh g -1 )和长期循环稳定性(1C下循环5000次后容量保持率为58.7%)。这项工作证明氢键工程设计高性能聚阴离子正极材料策略的可行,同时也为开发高性能钠离子电池正极材料提供了研究基础。