Interfacially Polymerized Polyamide Interlayer onto Ozonated Carbon Nanotube Networks for Improved Stability of Sulfur Cathodes

Lithium–sulfur (Li–S) batteries are considered promising energy‐storage devices owing to the high specific capacity and low cost of the S cathode. However, they suffer from capacity decay and poor coulombic efficiency arising from the dissolution of long‐chain polysulfides and their shuttling. A facile and scalable method was developed to directly coat a thin (≈57.3 nm) and porous polyamide (PA) interlayer onto a S cathode by interfacial polymerization. This PA interlayer prevented the shuttling of polysulfides by creating a physical barrier and, through chemical interactions between the amide functionalities of PA and the polysulfides, allowing access to the S electrode by the Li ions. The resulting PA‐coated cathode exhibited approximately 64.2 % capacity retention over 1000 cycles at 1 C with only 0.0358 % decay per cycle and a moderate capacity of 1008 mAh g −1 at 0.1 C.