Reduced Graphene Oxide - Molybdenum Disulfide Aerogel Nanocomposite Electrodes for Supercapacitors

2018-11-25
Aydınlı, Alptekin
Doğan, Öznur
Koylan, Serkan
Bat, Erhan
Ünalan, Hüsnü Emrah
Supercapacitors have attracted extensive attention for their high specific power and moderate energy densities. Nanoscale structure and high surface area are the two main requirements for a supercapacitor electrode with high performance. We report on the fabrication and electrochemical characterization of hybrid aerogel nanocomposite supercapacitor electrodes composed of reduced graphene oxide and molybdenum disulfide nanosheets on nickel foams. Graphene oxide was produced using Tour Method. Reduced graphene oxide (rGO) aerogel was produced from graphene oxide dispersion via solvothermal technique followed by freeze-drying and thermal reduction. For the fabrication of hybrid electrodes, produced rGO aerogels were simply pressed onto nickel foams, which was followed by drop-casting of exfoliated molybdenum disulfide (MoS2) nanosheets onto the rGO aerogel. Electrochemical properties such as specific capacity and capacity retention of the fabricated nanocomposite electrodes were examined through cyclic voltammetry, chronopotentiometry and electrochemical impedance spectroscopy in two electrode configuration. Results of the measurements were compared to that of control samples fabricated simply by pressing bare rGO aerogel and bare MoS2 nanosheets directly onto nickel foams. In order to determine the effect of electrolyte type on the electrochemical properties of the hybrid nanocomposite electrodes, various environmentally friendly and neutral aqueous solutions, such as lithium sulfate (Li2SO4), sodium sulfate (Na2SO4), sodium chloride (NaCl) and potassium chloride (KCl) were investigated as the electrolytes. Fabricated hybrid supercapacitor electrodes showed encouraging results with a specific capacitance of 38.69 mF/cm2 and a Coulombic efficiency of 83%. Following 1000 charge/discharge cycles, specific capacitance of the fabricated electrodes degraded to 94% of its initial capacitance value. A comprehensive analysis on the electrochemical properties of the fabricated supercapacitor will be presented

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Citation Formats
A. Aydınlı, Ö. Doğan, S. Koylan, E. Bat, and H. E. Ünalan, “Reduced Graphene Oxide - Molybdenum Disulfide Aerogel Nanocomposite Electrodes for Supercapacitors,” presented at the 2018 MRS Fall Meeting Exhibit, (25 - 30 Kasım 2018), Boston, Amerika Birleşik Devletleri, 2018, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/85798.