Graphene-supported Ce - SnS ₂ nanocomposite as anode material for lithium-ion batteries

A graphene-supported Ce-SnS₂ (Ce-SnS₂/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-SnS₂ 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-SnS₂ composite is 80 wt.% in the as-synthesized sample. The Ce-SnS₂/graphene 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.