Nanostructured MoS2/Graphene Composite As Superior Anode Material for Li-Ion Batteries

Abstract

To meet rising demands for energy density of lithium ion batteries (LIBs), a novel nanostructured MoS2/graphene (MoS2/G) composite with MoS2 nanoplates (NPs) perpendicularly grown on graphene sheets was prepared by a facile hydrothermal method. The direct coupling of edge Mo of MoS2 lattice with oxygen of functional groups from graphene oxide (forming C-O-Mo bond) is achieved by adjusting the synthesis parameters, which is beneficial to the electron transport and structural stability of MoS2/G electrode, and thus to the improvement of rate performance and long-cycle life of the electrode. The graphene sheets can enhance the electrical conductivity of the composite and meanwhile act not only as a substrate to disperse active MoS2 NPs homogeneously but also a cushion to accommodate the volume change during cycling. As an anode material for LIBs, MoS2/G manifests a high specific capacity (1077 mAh g-1 at 100 mA g-1 after 150 cycles), excellent rate capability and a stable cycling performance (907 mAh g-1 at 1000 mA g-1 after 400 cycles). The prepared MoS2/G composite is a promising anode material for next generation high performance LIBs.