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

2016-01-01
ATEŞ, MURAT
Cinar, Damla
Caliskan, Sinan
GEÇGEL, ÜNAL
ÜNER, OSMAN
BAYRAK, YÜKSEL
Candan, Idris
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.
FULLERENES NANOTUBES AND CARBON NANOSTRUCTURES

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Citation Formats
M. ATEŞ et al., “Active carbon/graphene hydrogel nanocomposites as a symmetric device for supercapacitors,” FULLERENES NANOTUBES AND CARBON NANOSTRUCTURES, pp. 427–434, 2016, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/68434.