【摘要】 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.更多还原

【Abstract】 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.更多还原