Strong Lithium Polysulfide Chemisorption on Electroactive Sites of Nitrogen‐Doped Carbon Composites For High‐Performance Lithium–Sulfur Battery Cathodes1. (6th February 2015)

• Record Type: Journal Article
• Authors: Song, Jiangxuan; Gordin, Mikhail L.; Xu, Terrence; Chen, Shuru; Yu, Zhaoxin; Sohn, Hiesang; Lu, Jun; Ren, Yang; Duan, Yuhua; Wang, Donghai
• Is Part Of: Angewandte Chemie. Volume 127:Number 14(2015)
• Page Start: 4399
• Page End: 4403
• Publication Date: 2015-02-06
• Subjects: Chemisorption -- Dotierung -- Elektrochemie -- Kohlenstoffmaterialien -- Lithium‐Schwefel‐Batterien; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201411109
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Despite the high theoretical capacity of lithium–sulfur batteries, their practical applications are severely hindered by a fast capacity decay, stemming from the dissolution and diffusion of lithium polysulfides in the electrolyte. A novel functional carbon composite (carbon‐nanotube‐interpenetrated mesoporous nitrogen‐doped carbon spheres, MNCS/CNT), which can strongly adsorb lithium polysulfides, is now reported to act as a sulfur host. The nitrogen functional groups of this composite enable the effective trapping of lithium polysulfides on electroactive sites within the cathode, leading to a much improved electrochemical performance (1200 mAh g −1 after 200 cycles). The enhancement in adsorption can be attributed to the chemical bonding of lithium ions by nitrogen functional groups in the MNCS/CNT framework. Furthermore, the micrometer‐sized spherical structure of the material yields a high areal capacity (ca. 6 mAh cm −2 ) with a high sulfur loading of approximately 5 mg cm −2, which is ideal for practical applications of the lithium–sulfur batteries.