Improved electrochemical performance of ternary Sn-Sb-Cu nanospheres as anode materials for lithium-ion batteries

摘要

Ternary Sn-Sb-Cu alloy nanoparticles were successfully synthesized via co-reduction of metal chlorides in aqueous alkaline solution.The results of the transmission electron microscopy(TEM)show that the as prepared Sn-Sb-Cu nanoparticles have a specific hollow structure with a uniform particle size of 10-20 nm.As there are not any hard templates in the synthesis system,a galvanic displacement reaction mechanism is proposed to account for the formation of the hollow nanostructures.When the alloy powders are used as anode materials for lithium-ion batteries,they exhibit relatively high electrochemical capacity and good cyclic retention.The good electrochemical performance can be attributed to the inactive Cu species.During electrochemical reactions,the inactive copper phase in the hollow structure serves as a soft and ductile matrix,which alleviates the mechanical stresses caused by the severe volume change during lithium insertion and extraction.With their high reversible capacities,the Sn-Sb-Cu alloys are a promising candidate as the anode material of rechargeable lithium-ion batteries.