Heterogeneous-Interface-Induced Charge Redistribution Toward Fe-Based Polyanion Cathode for Advanced Sodium-Ion Batteries

Na4Fe3(PO4)2P2O7 (NFPP) is gradually developing into one of the most commercially prospective cathode materials for sodium-ion batteries. However, the inactive phase maricite-NaFePO4 (m-NFP) normally tends to be formed during the synthesis process of NFPP, as well as the intrinsic poor electronic conductivity, which impacts the realization of high Na-storage performance. Herein, for the first time, we have constructed a heterostructure in Fe-based polyanionic cathode materials by fine-tuning the stoichiometric ratio of the Na site; the inactive phase m-NFP is fully transformed to the active Na2FeP2O7 or NFPP. In NFPP-NFPO heterogeneous composites, density functional theory calculations reveal that the charge…

• NN
  National Natural Science Foundation of China

  Awards: 52102213, 52472089
• PG
  People's Government of Jilin Province

  Award: 20220502002GH
• DO
  Department of Science and Technology of Jilin Province

  Award: 20230101128JC