Core-shell structured MoS2@S spherical cathode with improved electrochemical performance for lithium-sulfur batteries

To suppress shuttling effect and improve electrochemical performance of the sulfur cathode for lithium-sulfur batteries, core-shell structured MoS 2 @S spherical cathode has been synthesized through a chemical route using MnCO 3 as template. The MoS 2 shells consist of MoS 2 nanosheets . For comparison, MoS 2 /S cathode has also been synthesized through melting and diffusion of sulfur to commercial MoS 2 powders. The electrochemical performance of the MoS 2 @S and MoS 2 /S cathodes have been evaluated using cyclic voltammetry , discharge/charge cycling, electrochemical impedance spectroscopy coupled with impedance fitting. The electrochemical performance of the MoS 2 @S spherical cathode has been much improved compared with that of MoS 2 /S. The capacity of the MoS 2 @S spheres can reach 1185.7   mA   h   g −1 at 0.2   C and 955.1   mA   h   g −1 at 1   C with initial-cycle coulombic efficiency of 90%. The capacity fading of each cycle is 0.1% during 200 lithiation/delithiation cycles. The MoS 2 @S spherical cathode with high cyclic capacity and stability is promising cathode candidate for lithium-sulfur batteries.