A facile and scalable process was developed for the synthesis of single-layer MoS 2 -graphene nanosheet (SL-MoS 2 -GNS) composites based on the concurrent reduction of (NH 4 ) 2 MoS 4 and graphene oxide sheets by hydrazine in the presence of cetyltrimethylammonium bromide (CTAB), followed by annealing in a N 2 atmosphere. The morphology and microstructure of the composites were examined by X-ray diffraction, field emission scanning electron microscopy, high-resolution transmission electron microscopy and Raman spectroscopy. The formation process for the SL-MoS 2 -GNS composites was also investigated. The SL-MoS 2 -GNS composites delivered a large reversible capacity and good cycle stability as a Li-ion battery anode. In particular, the composites easily surpassed MoS 2 in terms of rate performance and cycle stability at high current densities. Electrochemical impedance spectroscopy revealed that the GNS in the composite not only reduced the contact resistance in the electrode but also significantly facilitated the electron transfer in lithiation and delithiation reactions. The good electrochemical performance of the composites for reversible Li + storage could be attributed to the synergy between the functions of SL-MoS 2 and GNS.

A cationic surfactant-assisted hydrothermal route is developed for the facile synthesis of graphene-like MoS2 /graphene (GL-MoS2 /G) composites based on the hydrothermal reduction of Na2 MoO4 and graphene oxide sheets with L-cysteine in the presence of cetyltrimethylammonium bromide (CTAB), following by annealling in N2 atmosphere. The GL-MoS2 /G composites are characterized by X-ray diffraction, electron microscopy, high-resolution transmission electron microscopy, and Raman spectroscopy. The effects of CTAB concentration on the microstructures and electrochemical performances of the composites for reversible Li(+) storage are investigated. It is found that the layer number of MoS2 sheets decreases with increasing CTAB concentration. The GL-MoS2 sheets in the composites are few-layer in the case of 0.01∼0.03 mol L(-1) CTAB of hydrothermal solution and single-layer in the case of 0.05 mol L(-1) CTAB. The GL-MoS2 /G composites prepared with 0.01-0.02 mol·L(-1) of CTAB solution exhibit a higher reversible capacity of 940-1020 mAh g(-1) , a greater cycle stability, and a higher rate capability than other samples. The exceptional electrochemical performance of GL-MoS2 /G composites for reversible Li(+) storage could be attributed to an effective integration of GL-MoS2 sheets and graphene that maximizes the synergistic interaction between them.

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