Realizing Li−S Batteries with Efficient Polysulfide Trapping and Conversion by using a High‐Nitrogen‐Content‐Doped Fe−N−C Porous Carbon Nanosheet‐Modified Separator

Abstract Lithium‐sulfur (Li−S) batteries with high theoretical energy density have earned much attention in recent years. Nevertheless, the shuttle effect and tardy conversion of polysulfides severely hinder their practical applications. Herein, the high‐nitrogen‐doped Fe−N−C porous carbon nanosheets (denoted as AT−Fe−N−C−Me) were synthesized and coated on separator as an effective electrocatalyst for Li−S batteries. Benefiting from the hierarchical porous carbon structure and rich Fe−N x catalytic sites, the AT−Fe−N−C−Me coating layer can effectively suppress the polysulfides shuttling and promote their redox conversion simultaneously. As a result, the Li−S batteries with AT−Fe−N−C−Me modified separators deliver superior rate capability (785.5 mAh g −1 at 4.0 C) and cycling stability (capacity decay rate of 0.065 % per cycle over 1000 cycles at 1.0 C). This work provides a new strategy to design efficient electrocatalyst with high‐surface‐area porous structure for high‐performance Li−S batteries.