Enhanced electrochemical performance of few-layered MoS₂–rGO nanocomposite for lithium storage application

Abstract

Molybdenum disulphide, a two dimensional unique layered material with natural hexagonal structure with adjoining layers connected by Mo–S covalent bonds, and stacked by weak van der Waals forces is similar to graphite. It has adjoining layer spacing of 0.615 nm which is significantly wider than graphite (0.333 nm) and is fabricated by simple inert annealing process. The synthesized MoS₂ is composited with reduced graphene oxide sheets in 1:1 ratio to enhance its electrochemical performance by improving electrical conductivity. MoS₂–rGO nanocomposite manifested a high specific discharge capacity of 1523 mAh g⁻¹ at 70 mA g⁻¹ and sustained a capacity of 1270 mAh g⁻¹ at the end of 200 charge–discharge cycles demonstrating an excellent stability of the material. Nevertheless, the nanocomposite material also exhibited phenomenal rate capability by displaying specific capacities of 400 and 300 mAh g⁻¹ at high current densities of 700 and 1400 mA g⁻¹, respectively.