• 文献标题:   Graphene wrapping as a protective clamping layer anchored to carbon nanofibers encapsulating Si nanoparticles for a Li-ion battery anode
  • 文献类型:   Article
  • 作  者:   SHIN J, PARK K, RYU WH, JUNG JW, KIM ID
  • 作者关键词:  
  • 出版物名称:   NANOSCALE
  • ISSN:   2040-3364 EI 2040-3372
  • 通讯作者地址:   Korea Adv Inst Sci Technol
  • 被引频次:   34
  • DOI:   10.1039/c4nr03173c
  • 出版年:   2014

▎ 摘  要

Carbon nanofibers encapsulating Si nanoparticles (CNFs/SiNPs) were prepared via an electrospinning method and chemically functionalized with 3-aminopropyltriethoxysilane (APS) to be grafted onto graphene oxide (GO). As a result, the thin and flexible GO, which exhibits a negative charge in aqueous solution, fully wrapped around the APS-functionalized CNFs with a positive surface charge via electrostatic self-assembly. After the formation of chemical bonds between the epoxy groups on GO and the amine groups in APS via an epoxy ring opening reaction, the GO was chemically reduced to a reduced graphene oxide (rGO). Electrochemical and morphological characterizations showed that capacity loss by structural degradation and electrolyte decomposition on Si surface were significantly suppressed in the rGOwrapped CNFs/SiNPs (CNFs/SiNPs@rGO). Superior capacities were consequently maintained for up to 200 cycles at a high current density (1048 mA h g(-1) at 890 mA g(-1)) compared to CNFs/SiNPs without the rGO wrapping (304 mA h g(-1) at 890 mA g(-1)). Moreover, the resistance of the SEI layer and charge transfer resistance were also considerably reduced by 24% and 88%, respectively. The described graphene wrapping offers a versatile way to enhance the mechanical integrity and electrochemical stability of Si composite anode materials.