title: Graphene/Sulfur/Carbon Nanocomposite for High Performance Lithium-Sulfur Batteries.
abstract: Here, we report a two-step synthesis of graphene/sulfur/carbon ternary composite with a multilayer structure. In this composite, ultrathin S layers are uniformly deposited on graphene nanosheets and covered by a thin layer of amorphous carbon derived from β-cyclodextrin on the surface. Such a unique microstructure, not only improves the electrical conductivity of sulfur, but also effectively inhibits the dissolution of polysulfides during charging/discharging processes. As a result, this ternary nanocomposite exhibits excellent electrochemical performance. It can deliver a high initial discharge and charge capacity of 1410 mAh·g-¹ and 1370 mAh·g-¹, respectively, and a capacity retention of 63.8% can be achieved after 100 cycles at 0.1 C (1 C = 1675 mA·g-¹). A relatively high specific capacity of 450 mAh·g-¹ can still be retained after 200 cycles at a high rate of 2 C. The synthesis process introduced here is simple and broadly applicable to the modification of sulfur cathode for better electrochemical performance.
authors.affiliation: Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, No. 1219, Zhongguan West Road, Zhenhai District, Ningbo, Zhejiang 315201, China. jinkk@nimte.ac.cn.
authors.forename: Kangke
authors.initials: K
authors.lastname: Jin
authors.affiliation: Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, No. 1219, Zhongguan West Road, Zhenhai District, Ningbo, Zhejiang 315201, China. zhouxf@nimte.ac.cn.
authors.forename: Xufeng
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, No. 1219, Zhongguan West Road, Zhenhai District, Ningbo, Zhejiang 315201, China. liuzp@nimte.ac.cn.
authors.forename: Zhaoping
authors.initials: Z
authors.lastname: Liu
keywords: Li-S battery; graphene; sulfur; β-cyclodextrin