Layered CoMoS3.13@NCNTs with a Rod-Shaped Skeleton as the Cathode of Lithium–Sulfur Batteries

Lithium metal has considerable advantages as an anode for lithium–sulfur batteries (LSBs). However, LSBs are susceptible to the slow oxidation kinetics of the intermediate product polysulfides (LIPSs) and the tendency of lithium anodes to form lithium dendrites during charging and discharging. Herein, we constructed a porous rod-like skeleton with a metal–organic framework (MOF) as the main template to construct LSB cathodes. ZIF-67 was loaded onto MoO3 nanorods and vulcanized to form a CoMoS3.13 rod skeleton. Melamine was applied as an auxiliary carbon source to generate highly conductive carbon nanotubes, yielding the final hierarchical composites of CoMoS3.13@NCNTs. The unique layered hollow structure of the hierarchical composite CoMoS3.13@NCNTs, which resulted from the excellent exchange synergistic effect of bimetallic ions, exerts good physical constraints and accelerates the transfer and transformation of LIPSs. On the basis of the above advantages, CoMoS3.13@NCNTs showed excellent electrochemical performance when tested as the cathode material for LSBs, possessing an initial discharge specific capacity of 1372 mAh g–1 at 0.1 C and maintaining a low decay rate of 0.039% after 1000 cycles at 0.5 C. CoMoS3.13@NCNTs were also found to have an initial discharge specific capacity of 1372 mAh g–1 at 0.1 C and maintained a low attenuation rate of 0.039% after 1000 cycles at 0.5 C. They had a discharge specific capacity of 643 mAh g–1 after 120 cycles at 0.2 C under a high sulfur loading of 4.0 mg cm–2. This work provides a feasible concept for the preparation of cathode sulfur host materials for high-performance LSBs.