• 文献标题:   Synergy of Epoxy Chemical Tethers and Defect-Free Graphene in Enabling Stable Lithium Cycling of Silicon Nanoparticles
  • 文献类型:   Article
  • 作  者:   LIU W, LI HJ, JIN JL, WANG YZ, ZHANG Z, CHEN ZD, WANG Q, CHEN YG, PAEK E, MITLIN D
  • 作者关键词:   coulombic efficiency, graphene defect, silicon, solid electrolyte interphase sei, surface chemistry
  • 出版物名称:   ANGEWANDTE CHEMIEINTERNATIONAL EDITION
  • ISSN:   1433-7851 EI 1521-3773
  • 通讯作者地址:   Sichuan Univ
  • 被引频次:   6
  • DOI:   10.1002/anie.201906612 EA SEP 2019
  • 出版年:   2019

▎ 摘  要

We report a new approach for nanosilicon-graphene hybrids with uniquely stable solid electrolyte interphase. Expanded graphite is gently exfoliated creating "defect-free" graphene that is non-catalytic towards electrolyte decomposition, simultaneously introducing high mass loading (48 wt. %) Si nanoparticles. Silane surface treatment creates epoxy chemical tethers, mechanically binding nano-Si to CMC binder through epoxy ring-opening reaction while stabilizing the Si surface chemistry. Epoxy-tethered silicon pristine-graphene hybrid "E-Si-pG" exhibits state-of-the-art performance in full battery opposing commercial mass loading (12 mg cm(-2)) LiCoO2 (LCO) cathode. At 0.4 C, with areal capacity of 1.62 mAh cm(-2) and energy of 437 Wh kg(-1), achieving 1.32 mAh cm(-2), 340.4 Wh kg(-1) at 1 C. After 150 cycles, it retains 1.25 mAh cm(-2), 306.5 Wh kg(-1). Sputter-down XPS demonstrates survival of surface C-Si-O-Si groups in E-Si-pG after repeated cycling. The discovered synergy between support defects, chemical-mechanical stabilization of Si surfaces, and SEI-related failure may become key LIB anode design rule.