Multifunctional LDH/Co9S8 heterostructure nanocages as high-performance lithium–sulfur battery cathodes with ultralong lifespan

Abstract Layered double hydroxides (LDHs) are promising lithium polysulfides (LiPSs) mediators, but the implementation of LDHs-based cathodes as high-performance lithium-sulfur batteries (LSBs) is hindered by their poor electrical conductivity and limited active sites. Herein, we report a hollow NiCo-LDH/Co9S8 (H-LDH/Co9S8) heterostructure with ordered nanocage morphology by in situ transformations of ZIF-67. The H-LDH/Co9S8 heterostructure could physically inhibit the LiPSs diffusion and accommodate sufficient sulfur. The abundant exposed O- and Co-adsorption sites could firmly entrap LiPSs and electrocatalytically boosted their conversion kinetics. Moreover, the intimated interfaces of NiCo-LDH and Co9S8 domains endows a significantly improved electron conductivity and Li+ ion diffusivity. As a result, H-LDH/Co9S8 delivers a high discharge capacity of 1339.1 mAh g−1 at the current density of 0.1C and shows an ultrastable lifespan over 1500 cycles with a small capacity decay of 0.047% per cycle and stable coulombic efficiency above 98% at the current density of 1.0C. This work paves a new way to fabricate and utilize LDH materials as high-performance LSB cathodes and provides new insights into the multifunctional heterostructure as ultralong life span electrodes.