A Micro‐Nano Flower‐Like Na ₃ V ₂ (PO ₄ ) ₃ @C Constructed by Polar‐Driven H‐Bond Engineering Toward High‐Rate Sodium Storage

ABSTRACT 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.