Intertwined Nitrogen‐Doped Carbon Nanotube Microsphere as Polysulfide Grappler for High‐Performance Lithium‐Sulfur Batteries

Abstract A kind of yarn‐like nitrogen‐doped carbon nanotubes microsphere (NSCNT) is synthesized in one‐step synthesis, and sulfur is added by melting immersion to form carbon nanotube microspheres/sulfur composites (NSCNT/S). The morphology, structure and electrochemical property of the obtained NSCNT/S are explored by field‐emission scanning electron microscopy (FESEM), X‐ray diffraction (XRD) and electrochemical tests. The results show that NSCNT possesses a high N content and unique mesoporous carbon framework with large specific surface area of 1029 m 2 g −1 , which can not only favor rapid electron and Li‐ion transfer but also effectively mitigate dissolved polysulfides via strong chemical and physical adsorption. Due to the synergetic interaction of NSCNT, the NSCNT/S delivers a high initial discharge capacity of 1241.3 mAh g −1 at 0.1 C and large rate capacity of 1175.5 mAh g −1 at 1 C with ultralow capacity decay of 0.1 % per cycle and high areal mass loading of 3.1 mg cm −2 . This eco‐friendly NSCNT/S can offer an appealing improvement for the applications of high‐performance lithium‐sulfur batteries.