Graphene-Supported Ce-Sns_2 Nanocomposite As Anode Material For Lithium-Ion Batteries

摘要

A graphene-supported Ce-SnS_2 (Ce-SnS_2/graphene) nanocomposite has been synthesized via a hydrothermal route. Structure, morphology, and electrochemical properties of the composites were studied by means of XRD, SEM, TEM, Raman, XPS, TGA, and electrochemical measurements. The Ce-SnS_2 crystal particles with a flower-like structure were distributed on the graphene sheets (GNS). The particle sizes of each petal are in the range 50-100 nm with clear lattice fringes. The atomic ratio of Sn, S, Ce, C, and O is estimated to be 1:2:0.05:3.11:0.64 and the content of Ce-SnS_2 composite is 80 wt.% in the as-synthesized sample. The Ce-SnS_2/graph-ene composite exhibits high initial discharge capacity (1638.3 mah/g at 0.5 C), high capacity retention (707 mah/g at 0.5 C after 50 cycles), and good rate capability due to the synergy effect between Ce-SnS_2 nanoparticles and graphene nanosheets. The superior performance is ascribed to the presence of graphene keeping the structure stable.