Active carbon/graphene hydrogel nanocomposites as a symmetric device for supercapacitors


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Ates M., Cinar D., Caliskan S., Gecgel U., Uner O., Bayrak Y., ...More

FULLERENES NANOTUBES AND CARBON NANOSTRUCTURES, vol.24, pp.427-434, 2016 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 24
  • Publication Date: 2016
  • Doi Number: 10.1080/1536383x.2016.1174115
  • Title of Journal : FULLERENES NANOTUBES AND CARBON NANOSTRUCTURES
  • Page Numbers: pp.427-434
  • Keywords: thermal exfoliation, Symmetric supercapacitor, Energy density, Graphene hydrogel, Active carbon, Power density, HIGH-PERFORMANCE SUPERCAPACITORS, ELECTROCHEMICAL ENERGY-STORAGE, GRAPHENE-BASED COMPOSITES, REDUCED GRAPHITE OXIDE, CHEMICAL ACTIVATION, POROUS CARBON, SURFACE-AREA, REMOVAL, CONSTRUCTION, ELECTRODES

Abstract

Activated carbons (ACs) are successfully synthesized from Elaeagnus grain by a simple chemical synthesis methodology and demonstrated as novel, suitable supercapacitor electrode materials for graphene hydrogel (GH)/AC nanocomposites. GH/AC nanocomposites are synthesized via hydrothermal process at temperature of 180 degrees C. The low-temperature thermal exfoliation approach is convenient for mass production of graphene hydrogel (GH) at low cost and it can be used as electrode material for energy storage applications. The GH/AC nanocomposites exhibit better electrochemical performances than the pure GH. Electrochemical performance of the electrodes is studied by cyclic voltammetry, and galvanostatic charge-discharge measurements in 1.0 M H2SO4 solution. A remarkable specific capacitance of 602.36 Fg(1) (based on GH/AC nanocomposites for 0.4 g AC) is obtained at a scan rate of 1 mVs(1) in 1 M H2SO4 solution and 155.78 Fg(1) for GH. The specific capacitance was increased 3.87 times for GH/AC compared to GH electrodes. Moreover, the GH/AC nanocomposites for 0.2 g AC present excellent long cycle life with 99.8% specific capacitance retained after 1000 charge/discharge processes. Herein, ACs prepared from Elaeagnus grain are synthesized GH and AC supercapacitor device for high-performance electrical energy storage devices as a promising substitute to conventional electrode materials for EDLCs.