Activating the Inert Na1 Sites in Na2FePO4F Toward High Performance Sodium Storage

Huiqin Huang, Yufan Xia, Youchen Hao, Haosheng Li, Caiyun Wang, Tingting Shi, Xingyu Lu*, Muhammad Wakil Shahzad, Ben Bin Xu, Yinzhu Jiang

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

8 Citations (Scopus)

Abstract

Na2FePO4F, an iron-based fluorophosphate with facile 2D sodium ion channels, is considered as a promising cathode material for sodium-ion batteries because of low cost, resource abundance, and nontoxicity. However, its application is considerably restricted by the limited intrinsic electronic conductivity and specific capacity. Herein, a doping strategy represented by Cu2+ is proposed to boost the electrochemical performance, attributed to the derivation of a new active Na3 site originated from the inert Na1 site and the band gap reduction due to the d-orbital hybridization. Consequently, the as-obtained Na2Fe0.95Cu0.05PO4F/C composite can deliver an excellent rate capacity of 74 mAh g⁻1 at 20 C and a decent specific capacity of 119 mAh g⁻1 at 0.1 C, which is superior to the previously reported Na2FePO4F-based cathode materials. This study sheds new light on developing high performance fluorophosphates cathode materials via regulating the Na site and electronic structure.
Original languageEnglish
Article number2305109
JournalAdvanced Functional Materials
Volume33
Issue number47
Early online date13 Jul 2023
DOIs
Publication statusPublished - 16 Nov 2023

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