Hierarchical Porous MoS/C Nanospheres Self-Assembled by Nanosheets with High Electrochemical Energy Storage Performance.

To overcome the deficiency of the volume expansion of MoS as the anode material for lithium-ion batteries (LIBs), an effective strategy was developed to design hierarchical porous MoS/carbon nanospheres via a facile, easy-operated hydrothermal method followed by annealing. FESEM and TEM images clearly showed that nanospheres are composed of ultra-thin MoS/C nanosheets coated with carbon layer and possess an expanded interlayer spacing of 0.98 nm. As anodes for LIBs, MoS/carbon nanospheres deliver an initial discharge capacity of 1307.77 mAh g at a current density of 0.1 A g. Moreover, a reversible capacity of 612 mAh g was obtained even at 2 A g and a capacity retention of 439 mAh g after 500 cycles at 1 A g. The improved electrochemical performance is ascribed to the hierarchical porous structure as well as the intercalation of carbon into lattice spacing of MoS, which offers fast channels for ion/electron transport, relieves the influence of volume change and increases electrical conductivity of electrode. Meanwhile, the expanded interlayer spacing of MoS in MoS/C can decrease the ion diffusion resistance and alleviate the volumetric expansion during discharge/charge cycles.