Free-standing, curled and partially reduced graphene oxide network as sulfur host for high-performance lithium-sulfur batteries

• 来源期刊: 中国物理B（英文版）
• 关键词: lithium-sulfur batteries sulfur cathode curled reduced graphene oxide
• 年，卷（期）: 2018,（6）
• 页码范围: 459-465
• 页数: 7页
• 语种: 英文
• DOI: 10.1088/1674-1056/27/6/068101

摘要

Lithium-sulfur (Li-S) batteries have received more and more attention because of higher specific capacity and energy density of sulfur than current lithium-ion batteries.However,the low electrical conductivity of sulfur and its discharge product,and also the high dissolution of polysulfides restrict the Li-S battery practical applications.To improve their performances,in this work,we fabricate a novel free-standing,curled and partially reduced graphene oxide (CPrGO for short) network and combine it with sulfur to form a CPrGO-S composite as a cathode for Li-S battery.With sulfur content of 60 wt％,the free-standing CPrGO-S composite network delievers an initial capacity of 988.9 mAh·g-1.After 200 cycles,it shows a stable capacity of 841.4 mAh·g 1 at 0.2 C,retaining about 85％ of the initial value.The high electrochemical performance demonstrates that the CPrGO-S network has great potential applications in energy storage system.Such improved properties can be ascribed to the unique free-standing and continous CPrGO-S network which has high specific surface area and good electrical conductivity.In addition,oxygen-containing groups on the partially reduced graphene oxide are beneficial to preventing the polysulfides from dissolving into electrolyte and can mitigate the "shuttle effect".