Different Phase and Morphology Effect of Manganese Oxide on Electrochemical Performance for Supercapacitor Application

Abstract

Nanostructures of manganese oxides are a promising pseudocapacitive electrode material due to its eco-friendly, low cost, and intrinsically high capacity. In this work, we prepared monometallic manganese oxide Mn3O4, and MnO2 using a facile, one-step hydrothermal method at low processing temperature. The structural, morphological, elemental analysis of manganese oxide (Mn3O4 nanoparticles (NPs) and one-dimensional MnO2 nanowires (1-D NWs)) powders confirmed from XRD, TEM, SEM, and EDAX techniques. The prepared materials have the same crystal structure with different phase and morphology. The morphology information of prepared Mn3O4, MnO2 powders visualized from an electron microscope of TEM and SEM techniques as particle and wire type morphology. The electrochemical performance of fabricated individual Mn3O4 and MnO2 @ Ni foam electrodes exhibited specific capacitance around 182 and 243 F/g at a current density of 0.5 A/g from galvanostatic charge–discharge cycles measurement in presence of 1 M KOH compared with 0.5 M KOH electrolyte solution. Also, from these results, the morphology of MnO2 (NWs) has better specific capacitance than Mn3O4 (NPs) in 1 M KOH electrolyte solution.