Carbon/Sulfur Aerogel with Adequate Mesoporous Channels as Robust Polysulfide Confinement Matrix for Highly Stable Lithium–Sulfur Battery
Yan Yan, Peng Zhang, Zehua Qu, Minman Tong, Shuang Zhao, Zhiwei Li, Mingkai Liu, Zhiqun Lin
Abstract
The ability to restrict the shuttle of lithium polysulfide (LiPSn) and improve the utilization efficiency of sulfur represents an important endeavor toward practical application of lithium–sulfur (Li–S) batteries. Herein, we report the crafting of a robust 3D graphene-wrapped, nitrogen-doped, highly mesoporous carbon/sulfur (G-NHMC/S) hierarchical aerogel as an effective polysulfide confinement matrix for a highly stable Li–S battery. Rich polar sites of NHMC firmly anchor LiPSn on the matrix surface. Porous NHMC provides ample space for accommodating sulfur and cushioning its volume expansion. Moreover, graphene wrapped on NHMC/S not only physically hinders the LiPSn shuttle but also interconnects the isolated NHMC/S, thus increasing electron transfer rate. Taken together, triple confinement of G-NHMC/S aerogel synergistically retains the soluble LiPSn and displays a specific capacity of 1322 mAh g–1 and 1000-cycle life. As such, rationally designed 3D carbon/sulfur aerogel affords a unique platform to impart high energy density and stable electrodes for energy storage devices.