molybdenum disulfide;
graphene;
composites;
hydrothermal synthesis;
lithium ion storage;
HIGH-CAPACITY;
ION BATTERIES;
MOS2;
NANOSHEETS;
CARBON;
EXFOLIATION;
PERFORMANCE;
NANOCOMPOSITES;
NANOPARTICLES;
SHEETS;
D O I:
10.1002/smll.201300415
中图分类号:
O6 [化学];
学科分类号:
0703 ;
摘要:
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 Na2MoO4 and graphene oxide sheets with L-cysteine in the presence of cetyltrimethylammonium bromide (CTAB), following by annealling in N-2 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 approximate to 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 molL(-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.