Role of deposition temperature on physical and electrochemical performance of manganese oxide electrode material for supercapacitor application

Abstract

In the present work, Manganese dioxide (MnO2) with a nanothorn surface architecture was synthesized with a simple, industry scalable, and chemical approach, namely a one-step hydrothermal method. The structural, morphological, and surface area properties of the as-synthesized MnO2 nanostructures electrodes deposited at different deposition temperatures have been systematically characterized by using different characterization The supercapacitive properties of MnO2 electrodes were studied by using cyclic voltammetry, galvonastic charge-discharge, long-term cyclic stability, and electrochemical impedance techniques in 1 M Na2SO4 as electrolyte. The SEM micrographs show different morphologies like nanoflakes, nanoflowers, and nanothorn at concerning deposition temperature. Among all the electrodes of MnO2 nanostructures prepared, nanothorn-like MnO2 nanostructures deposited at 160 °C for 6 h delivered the highest specific capacitance value of 432.52 F/g at a scan rate of 5 mV/s and good cycling stability after 2000 cycles. The excellent large surface area and optimized charge transfer pathway mark the MnO2 and make it potential electrode material for energy storage applications.