• 文献标题:   Hierarchical 3D All-Carbon Composite Structure Modified with N-Doped Graphene Quantum Dots for High-Performance Flexible Supercapacitors
  • 文献类型:   Article
  • 作  者:   LI Z, LIU X, WANG L, BU F, WEI JJ, PAN DY, WU MH
  • 作者关键词:   allcarbon composite, carbon nanotube, carbonized mof material, ndoped graphene quantum dot, supercapacitor
  • 出版物名称:   SMALL
  • ISSN:   1613-6810 EI 1613-6829
  • 通讯作者地址:   Shanghai Univ
  • 被引频次:   16
  • DOI:   10.1002/smll.201801498
  • 出版年:   2018

▎ 摘  要

Flexible supercapacitors have shown enormous potential for portable electronic devices. Herein, hierarchical 3D all-carbon electrode materials are prepared by assembling N-doped graphene quantum dots (N-GQDs) on carbonized MOF materials (cZIF-8) interweaved with carbon nanotubes (CNTs) for flexible all-solid-state supercapacitors. In this ternary electrode, cZIF-8 provides a large accessible surface area, CNTs act as the electrical conductive network, and N-GQDs serve as highly pseudocapactive materials. Due to the synergistic effect and hierarchical assembly of these components, N-GQD@cZIF-8/CNT electrodes exhibit a high specific capacitance of 540 F g(-1) at 0.5 A g(-1) in a 1 m H2SO4 electrolyte and excellent cycle stability with 90.9% capacity retention over 8000 cycles. The assembled supercapacitor possesses an energy density of 18.75 Wh kg(-1) with a power density of 108.7 W kg(-1). Meanwhile, three supercapacitors connected in series can power light-emitting diodes for 20 min. All-solid-state N-GQD@cZIF-8/CNT flexible supercapacitor exhibits an energy density of 14 Wh kg(-1) with a power density of 89.3 W kg(-1), while the capacitance retention after 5000 cycles reaches 82%. This work provides an effective way to construct novel electrode materials with high energy storage density as well as good cycling performance and power density for high-performance energy storage devices via the rational design.