Hierarchical MoS2/Carbon Composite Microspheres as Advanced Anodes for Lithium/Sodium-Ion Batteries

It is crucial to design advanced electrodes with large Li/Na-ion storage capacities for the development of next-generation battery systems. Herein, hierarchical MoS2/C composite microspheres were constructed by facile template-free self-assembly sulfurization plus post-carbonization. Cross-linked MoS2 nanosheets and outer carbon layer are organically combined together to form composite microspheres with diameters of 400-500 nm. Due to enhanced electrical conductivity and good structural stability, the MoS2/C composite microspheres exhibit substantially improved Li/Na-ion storage performance. Compared to unmodified MoS2, MoS2/C composite microspheres deliver higher Li/Na-ion storage capacity (Li+: 1017 mA hg(-1) at 100 mA g(-1) and Na+: 531 mA hg(-1) at 100 mA g(-1)), as well as better rate capability (Li+: 434 mA hg(-1) at 1 Ag-1 and Na+: 102 mA hg(-1) at 1 Ag-1) and capacity retention (Li+: 902 mA hg(-1) after 200 cycles and Na+: 342 mA hg(-1) over 100 cycles). The superior Li/Na-ion storage performance is mainly attributed to the unique porous microsphere architecture with increased electrode/electrolyte interfaces and more diffusion paths for Li/Na ion insertion. Additionally, the carbon coating can not only improve the electronic conductivity, but also suppress the shuttle effect of polysulfides.