title: Holey graphene frameworks for highly efficient capacitive energy storage.
abstract: Supercapacitors represent an important strategy for electrochemical energy storage, but are usually limited by relatively low energy density. Here we report a three-dimensional holey graphene framework with a hierarchical porous structure as a high-performance binder-free supercapacitor electrode. With large ion-accessible surface area, efficient electron and ion transport pathways as well as a high packing density, the holey graphene framework electrode can deliver a gravimetric capacitance of 298 F g(-1) and a volumetric capacitance of 212 F cm(-3) in organic electrolyte. Furthermore, we show that a fully packaged device stack can deliver gravimetric and volumetric energy densities of 35 Wh kg(-1) and 49 Wh l(-1), respectively, approaching those of lead acid batteries. The achievement of such high energy density bridges the gap between traditional supercapacitors and batteries, and can open up exciting opportunities for mobile power supply in diverse applications.
authors.affiliation: Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA.
authors.forename: Yuxi
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA.
authors.forename: Zhaoyang
authors.initials: Z
authors.lastname: Lin
authors.affiliation: Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA.
authors.forename: Xing
authors.initials: X
authors.lastname: Zhong
authors.affiliation: Department of Materials Science and Engineering, University of California, Los Angeles, California 90095, USA.
authors.forename: Xiaoqing
authors.initials: X
authors.lastname: Huang
authors.affiliation: Department of Materials Science and Engineering, University of California, Los Angeles, California 90095, USA.
authors.forename: Nathan O
authors.initials: NO
authors.lastname: Weiss
authors.affiliation: 1] Department of Materials Science and Engineering, University of California, Los Angeles, California 90095, USA [2] California Nanosystems Institute, University of California, Los Angeles, California 90095, USA.
authors.forename: Yu
authors.initials: Y
authors.lastname: Huang
authors.affiliation: 1] Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA [2] California Nanosystems Institute, University of California, Los Angeles, California 90095, USA.
authors.forename: Xiangfeng
authors.initials: X
authors.lastname: Duan