Iron single atom catalyst anchored on nitrogen-rich MOF derived carbon nanocage to accelerate polysulfide redox conversion for lithium sulfur batteries
Lithium sulfur batteries (LSBs) have been strongly considered as the most auspicious candidate for the next-generation energy storage devices owing to their higher energy density. However, the dissolution of lithium polysulfides (LiPSs) and sluggish conversion kinetics during charge/discharge cycling persecute the LSBs. Herein, we employ the nanocage-like nitrogen-rich metal organic frameworks (MOF) derived carbon decorated with iron single atom (FeSA-CN) catalyst to trigger the surface mediated reaction of LiPSs. The synergistic effect from the iron single atom (FeSA) and nitrogen-rich porous carbon significantly boost the reaction kinetics and utilization of sulfur species. FeSA-CN/S electrode could deliver a specific capacity of 1123 mAh g-1 at 0.2 C and exhibits an excellent rate performance of 605 mAh g-1 at 4.0 C with ultralow capacity fading rate of 0.06 % per cycle for 500 cycles. This work provides an effective strategy to couple the function of nanoporous materials host and single-atom catalyst for lithium sulfur batteries.