Galvanostatically deposited Fe: MnO2 electrodes for supercapacitor application

• Published in: The Journal of physics and chemistry of solids Vol. 73; no. 1; pp. 18 - 24
• Main Authors: Dubal, D.P., Kim, W.B., Lokhande, C.D.
• Format: Journal Article
• Language: English
• Published: 01.01.2012
• Subjects: Capacitors; Doping; Electrodes; Field emission; Iron; Scanning electron microscopy; Supercapacitors; X-rays
• ISSN: 0022-3697
• DOI: 10.1016/j.jpcs.2011.09.005

The present investigation describes the addition of iron (Fe) in order to improve the supercapacitive properties of MnO2 electrodes using galvanostatic mode. These amorphous worm like Fe: MnO2 electrodes are characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDAX), Fourier transform infrared spectroscopy (FTIR) and wettability test. The supercapacitive properties of MnO2 and Fe: MnO2 electrodes are investigated using cyclic voltammetry, chronopotentiometry and impedance techniques. It is seen that the supercapacitance increases with increase in Fe doping concentration and achieved a maximum of 173 F g-1 at 2 at% Fe doping. The maximum supercapacitance obtained is 218 F g-1 for 2 at% Fe: MnO2 electrode. This hydrous binary oxide exhibited ideal capacitive behavior with high reversibility and high pulse charge-discharge property between -0.1 and +0.9 V/SCE in 1 M Na2SO4 electrolyte indicating a promising electrode material for electrochemical supercapacitors.