Design Zwitterionic Amorphous Conjugated Micro‐/Mesoporous Polymer Assembled Nanotentacle as Highly Efficient Sulfur Electrocatalyst for Lithium‐Sulfur Batteries

Abstract

AbstractThe commercial application of lithium‐sulfur (LiS) batteries is seriously hampered by the sluggish redox kinetics and the shuttle effect of lithium polysulfides (LiPSs). In this study, a novel conjugated micro/mesoporous polymer (ST‐CMP) is developed by rational design of the organic condensation reaction of squaric acid and 1,3,5‐Tris(4‐aminophenyl)benzene, which can uniformly wrap onto carbon nanotube (CNT) as assembled nanotentacle, serving as the highly efficient sulfur electrocatalyst for LiS batteries. In this composite, the cross‐linked CNT conductive network significantly improves the electron transfer and reaction kinetics of active materials. In addition, the ST‐CMP assembled nanotentacle prevents the restacking or aggregation of ST‐CMP, favoring the exposure of active sites on ST‐CMP for efficient LiPSs chemical interaction. The abundant polymeric zwitterions in ST‐CMP with uniformly distributed positively polarized N atoms and negatively polarized O atoms can not only empower comprehensive regulation of LiPSs adsorption, but also simultaneously allow accelerated LiPSs catalytic conversion, rendering admirable redox reaction kinetics. With these merits, the obtained S/ST‐CMP@CNT composites exhibit a high initial specific capacity of 1307 mAh g−1 at 0.2 C with an ultralow capacity fading rate of 0.047% per cycle after 500 cycles at 1 C, exhibiting great potential in developing LiS batteries with decent performance.