Trapping sulfur in hierarchically porous, hollow indented carbon spheres: a high-performance cathode for lithium–sulfur batteries. Issue 24 (1st June 2016)

• Record Type: Journal Article
• Authors: Zhong, Yijun; Wang, Shaofeng; Sha, Yujing; Liu, Meilin; Cai, Rui; Li, Li; Shao, Zongping
• Is Part Of: Journal of materials chemistry. Volume 4:Issue 24(2016)
• Page Start: 9526
• Page End: 9535
• Publication Date: 2016-06-01
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c6ta03187k
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : Hierarchically porous hollow carbon spheres with an indented void structure have been designed as hosts for high-performance cathode materials for lithium–sulfur batteries. Abstract : Hierarchically porous hollow carbon spheres with an indented void structure have been designed as hosts for high-performance cathode materials for lithium–sulfur batteries. With a diameter of approximately 100 nm and a pore volume of 3.72 cm 3 g −1, the hosts can retain sulfur within the porous structures, including the external cone-like cavities, the porous carbon shells, and the inner linings. The exquisite indented structure provides excellent electron and Li-ion pathways while the symmetrically indented voids evenly alleviate the stress induced by the volume change during cycling. The oxygen functional groups further relieve the shuttle effect of polysulfide. A composite electrode with 52% sulfur loading demonstrates a remarkable initial discharge capacity of 1478 mA h g −1 at 1/10C (1C = 1675 mA g −1 ), corresponding to 88% sulfur utilization. Even when the sulfur/carbon (S/C) ratio of the composite is increased threefold from 1 : 1 to 3 : 1 (75% sulfur loading), a very high capacity retention is still maintained, achieving an ultraslow rate of capacity fading, ∼0.047% per cycle over 1200 cycles at 1/2C.