Hierarchical worm-like MoS2 structures directionally assembled with nanosheets are successfully synthesized via a simple hydrothermal route using potassium sodium tartrate as a structure-directing agent.

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Co-doped Zn 2 SnO 4 -graphene-carbon nanocomposites have been prepared for the first time through a convenient one-step hydrothermal method. The size of Co-doped Zn 2 SnO 4 nanoparticles is about 3-5 nm and they are well dispersed on graphene nanosheets and carbon layer. L-Ascorbic acid is introduced to serve as a reductant for GO and carbon sources. The doping of Co can enhance the crystalline degree of Zn 2 SnO 4 nanoparticles. When evaluated as anode materials for lithium ion batteries, the Co-ZTO-G-C nanocomposites exhibited a significantly higher reversible capacity of 699 mA h g À1 after 50 cycles at 100 mA g À1 and an improved cycling stability of 461 mA h g À1 after 200 cycles at 500 mA g À1 compared with Co-ZTO-G and ZTO-G-C nanocomposites. Moreover, even at a high current density of 1000 mA g À1 , the reversible capacity of 418 mA h g À1 still remained. The improved electrochemical performance can be attributed to the synergy of the graphene substrate, the protective carbon layer, the uniform ultrafine Zn 2 SnO 4 nanoparticles and Co doping. Therefore, Co-ZTO-G-C nanocomposites show great prospect as anodes for lithium-ion batteries.

Assembling sulfur spheres on carbon fiber with graphene coated hybrid bulk electrodes for lithium sulfur batteries.