Half-cell and full-cell investigations of 3D hierarchical MoS2/graphene composite on anode performance in lithium-ion batteries

摘要

A novel 3D hierarchical MoS2/graphene (MoS2/GN) composite is designed by a facile one-step hydrothermal co-assembling method without using any templates. SEM and TEM images show that the MoS2/GN flower-like particles are self-assembled by MoS2 nanoflakes and graphene nanosheets. According to the hydrothermal method used and characterization results observed, the formation process is proposed. Electrochemical performances of the MoS2/GN composite as anode active material in Lithium-ion batteries (LIBs) is investigated in both MoS2/GN//Li half-cells and MoS2/GN//LiCoO2 full-cells. The MoS2/GN composite delivers high initial discharge capacities of 1240 mAh g(-1) and good capacity retentions (about 80%) after more than 80 cycles in half-cells. Furthermore, the assembled MoS2/GN//LiCoO2 full-cell delivers high initial discharge capacities of 1203 mAh g(-1). The excellent lithium storage performances of the obtained MoS2/GN composite can be mainly attributed to the designed novel structure of the composite. The cross-linked graphene nanosheets, the anchoring MoS2 nanoflakes and the synergistic effects between them make the composite good conductivity, enough buffering space for the volume change, and shortened ionic transport length. This work clearly demonstrates that the MoS2/GN composite is a promising alternative material for anode in the LIB applications. (C) 2015 Elsevier B.V. All rights reserved.