In situ transformation of LDH into hollow cobalt-embedded and N-doped carbonaceous microflowers as polysulfide mediator for lithium-sulfur batteries

The shuttle effect of soluble lithium polysulfides (LiPSs), accompanying with sluggish redox kinetics has severely impeded the implementation of lithium-sulfur (Li-S) batteries. Herein, a novel hollow cobalt-embedded and nitrogen-doped carbonaceous microflower (H-Co-NCM) is fabricated via in situ transformation of metanilic anions intercalated Co-Al layered double hydroxides (CoAl LDHs). The as-obtained S@H-Co-NCM electrode exhibits superior electrocatalytic performances to boost the kinetics of LiPSs conversion and Li2S nucleation. Consequently, the assembled Li-S batteries with a high sulfur loading of 82% display a remarkable initial capacity of 1374 mAh g−1 at 0.1 C, excellent rate capability (611 mAh g−1 at 2 C), and superb cycle stability (cyclic decay rate of 0.069% over 500 cycles at 0.5 C). The integrated strategy of strong chemisorption and fast conversion of LiPSs provides deeper insights to suppress the shuttle effect.