Synthesis and characterization of MnO2 and NiO2 for supercapacitor applications

Abstract

The basic key points for an electrode of a supercapacitor are porous structure and high electrochemical surface area. Keeping this in mind, in this work we have successfully synthesised MnO2 and NiO2 over Nickel foam using a facile and efficient hydrothermal method and first time reporting the supercapacitor application. Ni foams show a good morphological porous structure of compromising rods and flower type that is a key parameter for supercapacitor studies. As the high surface area has been manifested as an important and necessary parameter in supercapacitor to store the charges, these structures provides efficient electrochemical surface area which is anticipated as a reason for good value of specific capacitance. The physio-chemical characterization of synthesized material was carried out by X-ray diffractometer (XRD) which shows the purity of the material, Field Emission Gun Scanning Electron Microscope (FESEM) showing the rod and flower shape structure and electrochemical performance was carried out by Cyclic Voltammetry (CV), Galvanostatic Charging Discharging (GCD) and Electrochemical impedance Spectroscopy (EIS) methods. CV analysis shows a specific capacitance of 2229 F/g at a scan rate of 1mV/s and 1833 F/g at a current density of 10mA, which proves that the synthesised material is suitable for the supercapacitor application.