Single-layer MoS2/graphene dispersed in amorphous carbon: towards high electrochemical performances in rechargeable lithium ion batteries

Abstract

Here we report a facile process to synthesize the novel nanocomposites comprised of single-layer MoS2, graphene and amorphous carbon (SL-MoS2/G@a-C) by a hydrothermal route employing sodium molybdate, sulfocarbamide, as-prepared graphene oxide and glucose as starting materials and then annealing in H2/N2 atmosphere at 800 °C. The samples were systematically investigated using X-ray diffraction, field emission scanning electron microscopy, and high-resolution transmission electron microscopy. It was demonstrated that the single-layer MoS2 and graphene in the composites dispersed highly uniformly in the amorphous carbon. The mechanism of the formation of SL-MoS2/G@a-C nanocomposites was investigated. It was found that the SL-MoS2/G@a-C nanocomposites exhibited very high reversible capacity with excellent cyclic stability and high-rate capability as anode materials of Li-ion batteries. Among three SL-MoS2/G@a-C samples, the SL-MoS2/G@a-C (1 : 1) nanocomposite delivered the largest reversible capacity (1116 mAh g−1) with negligible fading of the capacity after 250 cycles, and still retained a high specific capacity of 850 mAh g−1 and good cyclic stability at a high current density of 1000 mA g−1.