Co-doped g-C3N4 nanotube decorated separators mediate polysulfide redox for high performance lithium sulfur batteries. Issue 2 (20th December 2022)

• Record Type: Journal Article
• Authors: Fan, Zunhao; Zhu, Mengting; Deng, Shungui; Chen, Yanhua; Zhao, Yue; Qin, Mengyuan; Ma, Guiyuan; Wu, Jinghua; Xin, Xing
• Is Part Of: Nanoscale advances. Volume 5:Issue 2(2023)
• Page Start: 471
• Page End: 478
• Publication Date: 2022-12-20
• Subjects: 620.5
• DOI: 10.1039/d2na00645f
• Languages: English
• ISSNs: 2516-0230

Abstract

Abstract : A Co-doped g-C3N4 modified separator captures and converts polysulfides to realize the high utilization of S for Li–S batteries. Abstract : The main issue with lithium–sulfur (Li–S) batteries is the serious irreversible capacity loss caused by the polysulfide shuttle process. In this work, we propose an electro-catalytic strategy for absorbing and transferring long-chain polysulfides during the redox process, which is the key to improving the utilization of S. Reported here is a Co doped tubular g-C3 N4 (CN) modified separator (Co-TCN@PP), which successfully inhibited the polysulfide shuttle by physical absorption and catalysis, thus facilitating the high utilization of S. Co-TCN with a tube-like structure ensures the uniform dispersion of Co nanoparticles, which provides abundant active sites to absorb polysulfides. Furthermore, Co-TCN exhibits fast reaction kinetics for polysulfide conversion. A Li–S battery with Co-TCN@PP achieves superior rate capacities and a long cycle life (400 times) with capacity fading as low as 0.07% per cycle at a high Li + insertion/extraction rate of 2C. Moreover, electrodes with a high sulfur loading of 5.6 mg cm −2 can be realized by adopting the Co-TCN@PP separator.