Facile synthesis and stable lithium storage performances of Sn- sandwiched nanoparticles as a high capacity anode material for rechargeable Li batteries

摘要

A simple synthetic route was developed to obtain Sn-sandwiched composite nanoparticles by mechanical ball-milling ductile Sn particles with rigid SiC nanocores to form a SiC@Sn core-shell nanocomposite and then carbon-coating the SiC@Sn nanoparticles with graphite to produce the SiC@Sn@C nanoparticles. Such a novel nanostructure can effectively buffer the mechanical stress and prevent the aggregation of the Sn nanolayer and therefore improve the electrochemical utilization and cycling stability of electroactive Sn during Li-storage reaction. The Sn-sandwiched nanoparticles as-prepared exhibited a considerable high Li-storage capacity of ~600 mA h g~(-1) and an excellent cycling stability with ~90% capacity retention at 100 cycles, showing a prospect for practical lithium battery applications. In particular, the reported synthetic method is very simple, low-cost and pollution-free, enabling it to be readily adopted for large-scale production and also to be extended for other attractive lithium storage metals and alloys.