A reduced graphene oxide/Cu6Sn5 nanocomposite with enhanced cycling stability for lithium storage

We report a reduced graphene oxide (RGO)/Cu6Sn5 composite with enhanced lithium storage capability in which the nano-sized Cu6Sn5 is anchored on multi-layer graphene sheet using a soft chemical process. Being different from previous carbon modification technology, which usually loses the electronic path between the alloy particle and the supporting carbon medium after cycling, the graphene sheets provide a very useful buffer matrix for the volume change during lithiation and provide unique electronic conductivity. As a result, the RGO/Cu6Sn5 composite delivers a reversible capacity of 450 mAh g(-1) at a constant current density of 100 mA g(-1) between 0.0 and 2.0 V (versus Li(+)/Li), and exhibits excellent cycling stability with a capacity retention of 88% over 250 cycles.