High performance all-carbon thin film supercapacitors

JOURNAL OF POWER SOURCES

卷:274

Article

Liu, Jinzhang^1,2  Mirri, Francesca^3,4  Notarianni, Marco^1,2  Pasquali, Matteo^3,4  Motta, Nunzio^1,2 

[1] Queensland Univ Technol, Sch Chem Phys & Mech Engn, Brisbane, Qld 4001, Australia

[2] Queensland Univ Technol, Inst Future Environm, Brisbane, Qld 4001, Australia

[3] Rice Univ, Smalley Inst Nanoscale Sci & Technol, Dept Chem & Biomol Engn, Houston, TX 77005 USA

[4] Rice Univ, Smalley Inst Nanoscale Sci & Technol, Dept Chem, Houston, TX 77005 USA

关键词: Graphene;    Supercapacitor;    Carbon nanotubes;    Gelled electrolyte;    Electrochemical exfoliation;   

DOI  :  10.1016/j.jpowsour.2014.10.104

来源: Elsevier

【 摘 要 】

We fabricated high performance supercapacitors by using all carbon electrodes, with volume energy in the order of 10(-3) Whcm(-3), comparable to Li-ion batteries, and power densities in the range of 10 Wcm(-3), better than laser-scribed-graphene supercapacitors. All-carbon supercapacitor electrodes are made by solution processing and filtering electrochemically-exfoliated graphene sheets mixed with clusters of spontaneously entangled multiwall carbon nanotubes. We maximize the capacitance by using a 1:1 weight ratio of graphene to multi-wall carbon nanotubes and by controlling their packing in the electrode film so as to maximize accessible surface and further enhance the charge collection. This electrode is transferred onto a plastic-paper-supported double-wall carbon nanotube film used as current collector. These all-carbon thin films are combined with plastic paper and gelled electrolyte to produce solid-state bendable thin film supercapacitors. We assembled supercapacitor cells in series in a planar configuration to increase the operating voltage and find that the shape of our supercapacitor film strongly affects its capacitance. An in-line superposition of rectangular sheets is superior to a cross superposition in maintaining high capacitance when subject to fast charge/discharge cycles. The effect is explained by addressing the mechanism of ion diffusion into stacked graphene sheets. (C) 2014 Elsevier B.V. All rights reserved.

【 授权许可】

Free