Facile Synthesis of Graphene Encapsulated Co₂SnO₄ Nanoparticles as Enhanced Anode Materials for Lithium-Ion Batteries

A graphene encapsulated Co2SnO4 nanoparticles (Co2SnO4 NPs@rGO) was synthesized via the analogous mechanism of electrostatic interactions followed by thermal treatment. The Co2SnO4 NPs were uniformly encapsulated in the graphene sheets. As an anode material for rechargeable lithium batteries Co2SnO4 NPs@rGO exhibits enhanced cyclability and rate performance compared with free Co2SnO4 NPs. Even after 200 cycles, it still delivered large reversible capacity of 1037.9 mA h g-1 at 200 mA g-1. The excellent electrochemical performance should be associated with the uniform encapsulation of Co2SnO4 NPs by graphene sheets, which could not only effectively buffer the volume expansion and prevent the aggregation of the Co2SnO4 NPs but maintain good electrical conductivity of the whole electrode during the discharge/charge process.