Porous structure SnSb/amorphous carbon core-shell composite as high capacity anode materials for lithium ion batteries

SnSb/C core-shell powder has been successfully prepared by modified carbothermal reduction method. The shape, size, morphology, and electrochemical properties of the SnSb/C core-shell powder have been investigated. SnSb particles are completely encapsulated by amorphous carbon shell, and the surface of SnSb/C composite has been characterized with porous structure. The composite has a relatively high BET surface area of 253 m2g−1. The composite exhibits relatively good capacity retention for 50 cycles at a constant current density of 100 mA g−1 and show excellent rate performance when the current ranges from 50 to 200 mA g−1. The improvement of reversible capacity and cyclic performance is attributed to loose and amorphous surface structure which could buffer volume variations through cycle process.