Hydrothermal Synthesis of Nickel Manganese Ferrite (Ni0.5Mn0.5Fe2O4) and Cerium Oxide (CeO2) for Energy Storage Applications.

Abstract

This work presents the synthesis and characterization of a Ni0.5Mn0.5Fe2O4-CeO2 nanocomposite which is an improvement on the electrochemical performance of super capacitors. The composite has been prepared via co-precipitation route and its properties are determined by XRD, which verified the coexistence of spinel ferrite and fluorite CeO2 phases without having distorted structures. The Scherrer equation was used to calculate the average crystallite size, which was about 38nm, which means that the morphology is Nano-crystalline. The stabilization of the particle size and enhancement of the electrical conductivity with the introduction of CeO2 was achieved by their high oxygen storage and redox properties (Ce3+/Ce4+). In 1 M KOH electrolyte, electrochemical analyses were conducted in the form of cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS). The electrode of Ni0.5Mn0.5Fe2O4-CeO2 was a pseudocapacitive that was very reversible and had high rate capability. The composite was able to reach an energy density of 24.4 Wh/kg with a power density of 301.02 W/kg and maintain a good stability even after recharge-discharge cycles. It is believed that the enhanced electrochemical behavior is due to synergistic ferrite/ CeO2 interactions that promote ion diffusion and charge transfer. These findings include the fact that Ni0.5Mn0.5Fe2O4- CeO2 nanocomposites are potential material to be used in high-performance energy storage and catalytic applications.