Unlocking electrochemical potential:amorphous NaFePO_(4) as a high-capacity and cycle-stable cathode material for advanced sodium-ion batteries  

解锁电化学潜力:高比容量和长循环稳定的非晶NaFePO_(4)正极材料在先进钠离子电池中的应用

作　　者：Lixiao Han Shuxuan Liao Shihao Zhang Kean Chen Xumiao Chen Mengyi Li Qiang Li Xinping Ai Yuliang Cao Yongjin Fang 韩利晓;廖舒玄;张世豪;陈柯安;陈徐淼;李梦怡;李强;艾新平;曹余良;方永进

机构地区：[1]Hubei Key Laboratory of Electrochemical Power Sources,College of Chemistry and Molecular Sciences,Wuhan University,Wuhan 430072,China [2]College of Physics,University-Industry Joint Center for Ocean Observation and Broadband Communication,Weihai Innovation Research Institute,Qingdao University,Qingdao 266071,China

出　　处：《Science China Materials》2025年第4期1109-1116,共8页中国科学(材料科学)(英文版)

基　　金：supported by the National Natural Science Foundation of China(22209125,22479117,and U22A20438)。

摘　　要：Traditional cathode materials are well-defined high crystalline structures,but the repeated ion insertion/extraction with high lattice stress and volume change during the charge/discharge will cause structural degradation and diminish electrochemical performance.Herein we identify an amorphous iron phosphate electrode,NaFePO_(4),which can be rechargeable and show excellent electrochemical properties.The amorphous NaFePO_(4) electrode delivers a reversible capacity of 160.5 mAh g^(-1) at 20 mA g^(-1),accompanied by remarkable rate capability and cycling stability.Unlike conventional crystalline materials,the excellent electrochemical performance of the amorphous NaFePO_(4) electrode stems from the absence of lattice limitation in the amorphous structure,which allows for the accommodation of local stress and volume change during the long-term sodiation/desodiation processes.Further experimental characterizations and theoretical simulation reveal the underlying redox characteristics.This research offers some insights for the development of innovative amorphous electrode materials with low cost and attractive electrochemical properties for wide energy storage applications.传统的正极材料具有规整的晶格结构,在充放电过程中,由于离子的反复嵌入/脱出会引起晶格应力和体积变化,常常导致结构退化和电化学性能衰退.本文开发了一种非晶态NaFePO_(4)材料,显示出优异的电化学性能.非晶态NaFePO_(4)电极在20 mA g^(-1)的电流密度下具有160.5 mAh g^(-1)的可逆比容量,并且具有出色的倍率性能和循环稳定性.与传统的结晶材料不同,非晶态NaFePO_(4)电极优异的电化学性能源于非晶态结构不受晶格限制,能够缓解长期的钠离子嵌入/脱出过程中产生的局部应力和体积变化.实验表征和理论计算揭示了其内在的氧化还原特征.这项研究为开发低成本且具有优异电化学性能的非晶态电极材料提供参考.

关 键 词：amorphous NaFePO_(4) high capacity chemical presodiation cathode material sodium-ion batteries 

分 类 号：TM912[电气工程—电力电子与电力传动]