Sb@S–N–C nanocomposite as long-cycle stable anode material for lithium ion batteries

Antimony (Sb) is a competitive candidate for lithium ion batteries (LIBs) as anode material because of its high theoretical discharge capacity (660 mAh/g). However, it remains a challenge caused by the volume change in the process of charge and discharge, which would damage the Sb anode that lead to poor rate performance and low cycle stability. Herein, we report the synthesis of Sb@S–N–C nanocomposite as the anode material to solve the problem. First, SbSI nanowires with diameter of ∼10 nm were synthesized. Then the SbSI nanowires were coated with polypyrrole (PPy) to form SbSI@PPy core-shell nanowires. By thermal reduction of SbSI@PPy, Sb@S–N–C nanocomposite was formed. Using the Sb@S–N–C nanocomposite as the anode material, a capacity of 536 mAh/g was obtained in 100 cycles at 0.5 A/g. Excitingly, it also exhibited superior reversible and long-cycle non-decay stability with the capacity of 342 mAh/g in 2000 cycles at a high current density of 1A/g.