▎ 摘　　要

Carbon-coated Fe3O4 quantum dots/graphene composite was prepared via a hydrothermal and calcining process. XRD and TEM analysis revealed that carbon-coated Fe3O4 quantum dots with a size around 710 nm were distributed uniformly on graphene nanosheets. The carbon shell can preserve structural stabilization of Fe3O4 nanoparticles by preventing the aggregation and buffering the volume expansion during charge/discharge processes. In addition, the graphene nanosheets formed a three-dimensional network for the transportation of Li+ ions and electrons. When evaluated as anode material for lithium-ion batteries, the nanocomposite showed an improved lithium-storage performance with high cycling stability and good rate capacity. Furthermore, it exhibited an initial discharge capacity of 1300 mA h/g and retained a reversible capacity of about 940 mA h/g after 100 cycles at a current density of 150 mA/g. (C) 2014 Elsevier B.V. All rights reserved.