Graphene-based Pt/SnO^sub 2^ nanocomposite with superior electrochemical performance for lithium-ion batteries

Many metal oxides (e.g., SnO2) are deemed as promising anode materials for lithium-ion batteries due to their high theoretical capacities. However, the low electronic conductivity and large volume change of SnO2 during cycling hinder its practical application. In this work, graphene-based Pt/SnO2 composite is prepared by a modified electroless plating method and exhibits superior electrochemical performance compared to graphene-based SnO2 and Pt/SnO2 composites. The reversible capacity of graphene-based Pt/SnO2 is maintained at ~950 mA h g-1 at 0.1 C after 100 cycles and remains at ~470 mA h g-1 when the current density increases to 2 C. The graphene substrate can enhance the electronic conductivity of the composite and effectively buffer the strain from the volume variation of SnO2 during cycling. Moreover, the presence of Pt nanoparticles can separate SnO2 nanoparticles on the graphene and further facilitate electron transport in the composite, leading to the outstanding electrochemical performance of graphene-based Pt/SnO2. This kind of novel graphene-based metal/metal oxide composites may be potentially used as high-performance electrode materials for batteries and supercapacitors.