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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]