摘要
Antimony-based materials with high theoretical capacity are known as promising anodes for potassiumion batteries(PIBs). However, they still face challenges from the large ionic radius of the K ion, which has sluggish kinetics. Much effort is needed to exploit high-performance electrode materials to satisfy the reversible capacity of PIBs. In this paper, nano Sb confined in N-doped carbon fibers(Sb@CN nanofibers)were successfully prepared through an electrospinning method, which was designed to improve potassium storage performances. Sb@CN nanofibers benefit from the fact that the synergy between the porous nanofiber frame structure and the uniformly distributed Sb nano-components in the carbon matrix can effectively accelerate the ion migration rate and reduce the mechanical stress caused by K+insertion/extraction, Sb@CN nanofiber electrodes thus exhibited excellent potassium storage performance, especially long cycle stability, as expected. When utilized as a PIB anode, they delivered high reversible capacity of 360.2 m Ah g-1 after 200 cycles at 50 m A g-1, and a particularly stable capacity of 212.7 m Ah g-1 was also obtained after 1000 cycles even at 5000 m A g-1. Given such outstanding electrochemical performances,this work is expected to provide insight into the development and exploration of advanced alloy-type electrodes for PIBs.
通过静电纺丝技术制备了纳米级Sb@CN纤维复合材料,是一种潜在的钾离子电池电极材料.研究结果表明,多孔纳米纤维框架结构与均匀分布的Sb纳米组分之间的协同作用可以有效加速离子迁移速率,并缓解K+嵌入过程中引起的体积膨胀,从而使Sb@CN纳米纤维电极表现出优异的钾储存性能.尤其是其长循环稳定性,在5000 m A g–1电流密度下, 1000次循环后,仍可获得212.7 m Ah g–1的可逆容量,此高循环稳定性是目前高性能钾离子电池应用的关键指标.
作者
Danyang Liu
Li Yang
Zanyu Chen
Guoqiang Zou
Hongshuai Hou
Jiugang Hu
Xiaobo Ji
刘丹阳;杨莉;陈赞宇;邹国强;侯红帅;胡久刚;纪效波(College of Chemistry and Chemical Engineering and Hunan Province Key Laboratory of Chemical Power Source,Central South University,Changsha 410083,China;School of Materials Science and Engineering,Central South University.Changsha 410083,China;School of Materials Science and Engineering,Zhengzhou University,Zhengzhou 450001,China;Faculty of Materials Metallurgy and Chemistry,Jiangxi University of Science and Technology.Ganzhou 341000,China)
基金
supported by the National Natural Science Foundation of China(51904342,51622406,and 21673298)
the National Postdoctoral Program for Innovative Talents(BX201600192)
Central South University Postdoctoral Foundation(140050018)
China Postdoctoral Science Foundation(2017 M6203552)
the National Key Research and Development Program of China(2017YFB0102000,2018YFB0104200)
Hunan Provincial Science and Technology Plan(2017TP1001)
the Fundamental Research Funds for the Central Universities of Central South University(2019zzts431,2019zzts433)。
