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Graphene supported porous Si@C ternary composites had been synthesized by various routes and their structural, morphological and electrochemical properties were investigated. Porous Si spheres coated with carbon layer and supported by graphene have been designed to form a 3D carbon conductive network. Used as anode materials for lithium ion batteries, graphene supported porous Si@C ternary composites demonstrate excellent electrochemical performance and cycling stability. The first discharge capacity is 2184.7 mA h/g at a high current density of 300 mA/g. After 50 cycles, the reversible capacity is 652.4 mA h/g at a current density of 300 mA/g and the coulomb efficiency reaches at 98.7%. Due to their excellent electrochemical properties, graphene supported porous Si@C ternary composites can be a kind of promising anode materials for lithium ion batteries. [ABSTRACT FROM AUTHOR]

Abstract: The GNS/Li2SnO3/PPY ternary composites were synthesized by a deoxidation technique. The soft polymer matrix and flexible graphene provide a dual buffering structure for Li2SnO3 which synergistic leads to improved stability, enhanced electric conductivity and better electrochemical performance. The GNS/Li2SnO3/PPY composites tested as anode materials for lithium ion batteries exhibit a high reversible capacity of 699.4mAh/g over 30 cycles, which is much better than that of pure Li2SnO3, PPY/Li2SnO3 and GNS/Li2SnO3 composites. [Copyright &y& Elsevier]

Abstract: The carbon-doped Li2SnO3/graphene composites for lithium-ion batteries were synthesized by the hydrothermal route. The structure, morphology and electrochemical properties of the composites were detected by means of XRD, SEM, TEM, Raman, TGA and electrochemical measurements. The Li2SnO3 nanoparticles are surrounded by graphene sheets (GNS) and amorphous carbon layers. The carbon-doped Li2SnO3/graphene materials exhibit good electrochemical performance with high capacity and good cycling stability (736.3mAh/g after 50 cycles at 60mA/g).The presence of graphene sheets and carbon layer can alleviate the effects of volume changes, keep the structure stable and increase the conductivity. Conclusively, The C/Li2SnO3/GNS composites exhibit better electrochemical properties than GNS/Li2SnO3 and Li2SnO3. [Copyright &y& Elsevier]