BiCoS3-δ@Co1-xS异质结构纤维的制备及其作为锂离子电池负极材料的应用
Preparation of heterostructured BiCoS3-δ@Co1-xS fibers as anode materials in lithium-ion batteries
杨豪苗 1刘乐浩 1马峻峰 1吴卓恒 1张乔木1
作者信息
- 1. 华北电力大学新能源学院,北京 102200
- 折叠
摘要
金属硫化物因其高理论容量在锂离子电池领域受到广泛关注,但其低导电性和在循环过程中的显著体积变化限制了其实际应用.结合缺陷工程和异质结构,提出了一种提升金属硫化物负极材料电化学性能的有效策略.首先通过合成含硫空位缺陷的BiCoS3-δ纤维,不仅提供了更多的反应活性位点,还有效提升了材料的导电性.随后,在BiCoS3-δ纤维上原位生长Co1-xS,制备出具有异质结构的BiCoS3-δ@Co1-xS复合纤维,该BiCoS3-δ@Co1-xS异质结能够借助内建电场效应,显著促进电荷转移,增强了表面反应动力学,还能够利用异质界面的紧密接触增强纤维在充放电循环过程中的结构稳定性.因而,BiCoS3-δ@Co1-xS异质结构纤维展现出优异的电化学性能.尤其是在1.0 A/g电流密度下经过3000次循环后,BiCoS3-δ@Co1-xS电极仍保持高达413.5 mAh/g的容量,表现出了良好的循环稳定性.
Abstract
Metal sulfides(MSs)have been extensively studied in lithium-ion batteries owing to their high theo-retical capacity.However,their broad utilization is severely hindered by their poor conductivity and large volu-metric change during cycling.One strategy for enhancing the electrochemical performance of MSs anode materi-als is proposed here,based on the defect engineering and heterostructure design.BiCoS3-δ fibers with sulfur va-cancy defects are firstly synthesized,which can not only provide more reaction active sites,but also enhance the electrical conductivity.BiCoS3-δ@Co1-x S composite fibers with heterostructure are also prepared by the in-situ growth of Co1-xS on BiCoS3-δ fibers.The heterojunction formed within BiCoS3-δ@Co1-xS can favor the charge transfer and enhance the surface reaction kinetics due to the build-in electric field effect.Simultaneously,the tightly contacted interface would improve their structural stability during cycle.Therefore,the heterostructured BiCoS3-3@Co1-x S fibers have the best electrochemical performance.Especially,the BiCoS3-δ@Co1-x S elec-trode maintains a high capacity of 413.5 mAh/g even after 3000 cycles at 1.0 A/g,displaying the excellent cyc-ling stability.
关键词
异质结构/缺陷/纤维/负极/锂离子电池Key words
heterostructure/defect/fiber/anode/lithium-ion battery引用本文复制引用
出版年
2024
NETL
NSTL
万方数据