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Novel a - MoO 3 nanorods coated with SnS 2 nanosheets core-shell nanorod composite has been synthesized via two hydrothermal routes. More importantly, as the anode materials for lithium ion batteries, the MoO 3 @SnS 2 core-shell nanorod composite has not been investigated in detail. The one-dimensional core-shell nanorod composite has high surface area, which could offer larger contact area for material and electrolyte. In addition, there are large enough inner spaces between the SnS 2 nanosheets, which provides an efficient transport of electrons and ions. In addition, the core-shell nanostructure could accommodate the volume changes caused by the charge/discharge reaction and could avoid the agglomerations and pulverization of anode materials.As anode materials for LIBs, the as-prepared MoO 3 @SnS 2 core-shell nanorod composite displayed 1663.2mAh/g discharge capacity in the first cycle at the current of 60mA/g. After 100 cycles, the remained capacity is 568.2mAh/g, which is both higher than that of a-MoO 3 and SnS 2 . Considering the excellent electrochemical performance with high capacity and good cycling stability, the as-prepared the MoO 3 @SnS 2 core-shell nanorod composite has the potential to be the next generation anode materials for lithium ion batteries. [ABSTRACT FROM AUTHOR]

Hydriodic acid and self-assembly approach are used to fabricate graphene wrapped sulfur composite. The self-assembly process of the relative “large” graphene sheet and “small” sulfur is quite controllable, and the sulfur particles are completely enfolded by RGO sheets with a unique stacked structure .The RGO/S composite with 80 wt.% sulfur shows an initial discharge capacity of 865.1 mAh g −1 at 0.5 mA/cm 2 . A high specific capacity of 720 mAh g −1 with a coulombic efficiency of 95% is achieved after 50 cycles of charge/discharge. The material also delivered a capacity of more than 580 mAh g −1 at 2 mA/cm 2 and can be recovered to 736 mAh g −1 when the rate is returned to 0.2 mA/cm 2 , representing a promising cathode material for high current discharge lithium-sulfur batteries. [ABSTRACT FROM AUTHOR]

Hollow Zn 2 SnO 4 boxes@C/graphene ternary composites with a three-dimensional triple buffering structure are prepared by two hydrothermal processes followed by a calcined process. The structure, morphology and electrochemical properties of the ternary composites were investigated by means of XRD, FTIR, Raman, BET, BJH, SEM, TEM, and electrochemical measurements. The hollow Zn 2 SnO 4 boxes are coated with carbon layer and then supported by graphene sheets to form a 3D carbon conductive network. Compared with the hollow Zn 2 SnO 4 boxes@graphene binary composites, the hollow Zn 2 SnO 4 boxes@C binary composites, the hollow Zn 2 SnO 4 boxes and the solid Zn 2 SnO 4 cubes, the hollow Zn 2 SnO 4 boxes@C/graphene ternary composites show an enhanced electrochemical performance (726.9 mAh g −1 at a current density of 300 mA g −1 after 50 cycles) and high rate capability. With the unique structure design, this kind of composites with excellent electrochemical properties can be a promising anode material for lithium-ion batteries. [ABSTRACT FROM AUTHOR]