Spray-Drying Synthesis of Na<sub>4</sub>Fe<sub>3</sub>(PO4)<sub>2</sub>P<sub>2</sub>O<sub>7</sub>@CNT Cathode for Ultra-Stable and High-Rate Sodium-Ion Batteries
Jinri Huang,
Ziheng Zhang,
Daiqian Chen,
Hesheng Yu,
Yu Wu,
Yuanfu Chen
Affiliations
Jinri Huang
State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Integrated Circuit Science and Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China
Ziheng Zhang
State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Integrated Circuit Science and Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China
Daiqian Chen
State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Integrated Circuit Science and Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China
Hesheng Yu
State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Integrated Circuit Science and Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China
Yu Wu
State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Integrated Circuit Science and Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China
Yuanfu Chen
State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Integrated Circuit Science and Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China
Iron-based phosphate is a promising cathode for sodium-ion batteries due to its low cost and abundant resources; however, the practical application is hindered by poor electronic conductivity, sluggish Na+ diffusion, and a lack of low-cost and scalable synthesis methods. To address such issues, herein, we present a low-cost and scalable spray-drying strategy to synthesize Na4Fe3(PO4)2P2O7@CNT (NFPP@CNT) hollow microspheres. The NFPP@CNT composite has the following advantages: highly conductive CNT can significantly improve the electronic conductivity of the cathode, and the flexible CNT-based microsphere architecture facilitates Na+ diffusion and guarantees excellent mechanical properties to mitigate structural degradation during cycling. These merits make the NFPP@CNT cathode display outstanding electrochemical performances: the NFPP@CNT-1% electrode demonstrates a high reversible capacity of 103.9 mAh g−1 at 0.1 C and maintains a very high capacity retention of 99.9% after 1000 cycles even at a high rate of 5 C.
