• 文献标题:   A holey graphene-based hybrid supercapacitor
  • 文献类型:   Article
  • 作  者:   JEONG JH, LEE GW, KIM YH, CHOI YJ, ROH KC, KIM KB
  • 作者关键词:   hybrid supercapacitor, holey graphene, graphenebased material, lithium titanate
  • 出版物名称:   CHEMICAL ENGINEERING JOURNAL
  • ISSN:   1385-8947 EI 1873-3212
  • 通讯作者地址:   Yonsei Univ
  • 被引频次:   10
  • DOI:   10.1016/j.cej.2019.122126
  • 出版年:   2019

▎ 摘  要

Holey graphene with nano-sized holes has numerous electrochemically active sites and an open porous structure, imparting a higher electrocatalytic activity and faster electron and ion transport compared with basal planes in graphene. In this study, holey graphene-based electrode materials, prepared using holey graphene as building blocks, are applied in both electric double-layer capacitor-and lithium-ion battery-type electrodes, because holey graphene possesses more electrochemically active sites originating from the edge sites and facilitates faster electron/ion transport through the holes. The enhanced specific capacity of holey graphene can be attributed to its edge sites, because an additional electric double-layer is formed at the edges. The enhanced rate capability of the Li4Ti5O12/holey graphene composite can be attributed to the in-plane holes, because they enhance lithium-ion transport across the graphene to Li4Ti5O12. We successfully design a hybrid supercapacitor consisting of holey graphene and the Li4Ti5O12/holey graphene composite. The hybrid supercapacitor delivers a maximum energy density of 117.3 Wh.kg(-1) at a power density of 0.1 kW.kg(-1), and a maximum power density of 19.7 kW.kg(-1) is achieved at an energy density of 43.1 Wh.kg(-1). The outstanding energy and power density demonstrate the increased specific capacitance of the capacitor-type electrode and rate capability of the battery-type electrode.