Significant improvement in the electrochemical performances of nano-nest like amorphous MnO2 electrodes due to Fe doping

Amorphous and highly porous nanonest like Fe:MnO 2 thin films have been potentiostatically synthesized and are characterized by using X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Energy dispersive X-ray analysis (EDAX), Fourier transform infrared spectroscopy (FTIR), wettability test and optical properties. The supercapacitive performance of Fe:MnO 2 electrodes were tested using cyclic voltammetry (CV), charge-discharge and impedance techniques in 1 M Na 2SO 4 electrolyte. The effect of Fe doping on structural, morphological, compositional and supercapacitive properties of MnO 2 thin films has been investigated. Further, the effect of electrolyte concentration and scan rate on the supercapacitance of MnO 2 and Fe:MnO 2 electrodes have been studied. The results showed that as Fe doping concentration increases up to 2 at% the supercapacitance increases from 166 to 231 F g -1. The maximum specific capacitance of 273 F g -1 was achieved for 2 at% Fe:MnO 2 at 5 mV s -1 scan rate.