• 文献标题:   Freeze-Dried Sulfur-Graphene Oxide-Carbon Nanotube Nanocomposite for High Sulfur-Loading Lithium/Sulfur Cells
  • 文献类型:   Article
  • 作  者:   HWA Y, SEO HK, YUK JM, CAIRNS EJ
  • 作者关键词:   lithium/sulfur cell, energy storage, high sulfur loading, ionic liquid, in situ tem, aluminum foam
  • 出版物名称:   NANO LETTERS
  • ISSN:   1530-6984 EI 1530-6992
  • 通讯作者地址:   Lawrence Berkeley Natl Lab
  • 被引频次:   41
  • DOI:   10.1021/acs.nanolett.7b03831
  • 出版年:   2017

▎ 摘  要

The ambient-temperature rechargeable lithium/sulfur (Li/S) cell is a strong candidate for the beyond lithium ion cell since significant progress on developing advanced sulfur electrodes with high sulfur loading has been made. Here we report on a new sulfur electrode active material consisting of a cetyltrimethylammonium bromide-modified sulfur-graphene oxide-carbon nanotube (S-GO-CTA-CNT) nanocomposite prepared by freeze-drying. We show the real-time formation of nanocrystalline lithium sulfide (Li2S) at the interface between the S-GO-CTA-CNT nanocomposite and the liquid electrolyte by in situ TEM observation of the reaction. The combination of GO and CNT helps to maintain the structural integrity of the S-GO-CTA-CNT nanocomposite during lithiation/delithiation. A high S loading (11.1 mgS/cm(2), 75% S) S-GO-CTA-CNT electrode was successfully prepared using a three-dimensional structured A1 foam as a substrate and showed good S utilization (1128 mAh/g S corresponding to 12.5 mAh/cm(2)), even with a very low electrolyte to sulfur weight ratio of 4. Moreover, it was demonstrated that the ionic liquid in the electrolyte improves the Coulombic efficiency and stabilizes the morphology of the Li metal anode.