Ultra-stable Sb confined into N-doped carbon fibers anodes for high-performance potassium-ion batteries

• 来源期刊: 科学通报（英文版）
• 年，卷（期）: 2020,（12）
• 页码范围: 1003-1012
• 页数: 10页
• 语种: 英文

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 mAh g-1 after 200 cycles at 50 mA g-1,and a particularly stable capacity of 212.7 mAh g-1 was also obtained after 1000 cycles even at 5000 mA 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.