標題: Synthesis of Free-Standing Flexible rGO/MWCNT Films for Symmetric Supercapacitor Application
作者: Kumar, Amit
Kumar, Nagesh
Sharma, Yogesh
Leu, Jihperng
Tseng, Tseung Yuen
材料科學與工程學系
電子工程學系及電子研究所
Department of Materials Science and Engineering
Department of Electronics Engineering and Institute of Electronics
關鍵字: Graphene;Reduced graphene oxide;MWCNTs;Specific capacitance;Supercapacitor;Energy and power densities
公開日期: 6-八月-2019
摘要: Herein, we report a novel, simple, and cost-effective way to synthesize flexible and conductive rGO and rGO/MWCNT freestanding films. The effects of MWCNT addition on the electrochemical performance of rGO/MWCNT nanocomposite films are investigated in some strong base aqueous electrolytes, such as KOH, LiOH, and NaOH via three-electrode system. The supercapacitor behavior of the films is probed via cyclic voltammetry, galvanostatic charging-discharging, and electrochemical impedance spectroscopy. The structural and morphological studies of the films are performed by X-ray diffractometer, Raman spectrometer, surface area analyzer, thermogravimetric analysis, field emission scanning electron microscope and transmission electron microscope. The rGO/MWCNT film synthesized with 10 wt% MWCNTs (GP10C) exhibits high specific capacitance of 200 Fg(-1), excellent cyclic stability with 92% retention after 15,000 long cycle test, small relaxation time constant (similar to 194 ms), and high diffusion coefficient (7.8457 x 10(-9) cm(2) s(-1)) in 2 M KOH electrolyte. Furthermore, the symmetric supercapacitor coin cell with GP10C as both anode and cathode using 2 M KOH as electrolyte demonstrates high energy density of 29.4 Whkg(-1) and power density of 439 Wkg(-1) at current density 0.1 Ag-1 and good cyclic stability with 85% retention of the initial capacitance at 0.3 Ag-1 after 10,000 cycles. Such a high performance of the GP10C film in the supercapacitor can be ascribed to the large surface area and small hydration sphere radius and high ionic conductivity of K+ cations in KOH electrolyte.
URI: http://dx.doi.org/10.1186/s11671-019-3100-1
http://hdl.handle.net/11536/152581
ISSN: 1931-7573
DOI: 10.1186/s11671-019-3100-1
期刊: NANOSCALE RESEARCH LETTERS
Volume: 14
Issue: 1
起始頁: 0
結束頁: 0
顯示於類別:期刊論文