MoS2 confined within CMK-3 as multifunctional nanoreactor towards high-performance Li–S battery

Lithium-sulfur (Li–S) battery has been considered a promising energy-storage devices due to its high energy density and low cost. However, the low utilization of sulfur and rapid capacity degradation resulted from low conductivity of sulfur, shuttle effect of sulfides intermediates and slow reaction kinetics restrain its practical application. In this work, a sulfur host composite constructed by CMK-3 confining MoS2 nanoparticles was developed through a simple hydrothermal and post-annealing method. In this composite, most nano-size MoS2 nanoparticles are confined within the pores and channels of CMK-3 (MoS2@CMK-3), acting as a “restricted nanoreactor” shows multiple effect for lithium polysulfides (LiPSs). On the one hand, the highly conductive CMK-3 not only accelerate the electrons transfer, but also can physically capture soluble LiPSs through its abundant mesopores. More significantly, the active MoS2 within the nanoreactor exhibits a synergistic effect of strong chemical adsorption and subsequent catalytic conversion effect for LiPSs, which efficiently inhibits the shuttle effect. As a result, the as-prepared cathode based-MoS2-50@CMK-3 delivers a high specific capacity of 950.3 mA h g−1 at 2 C and still maintain a discharge specific capacity of 440.3 mA h g−1 after 1600 cycles with a capacity decay rate of 0.033 % per cycle. This work would guide the rational design of advanced sulfur cathodes for Li–S batteries.