Synthesis and characterization of Li_0.5Co_2.5O₄ spinel oxide for electrochemical performance

A nanocrystalline material of Li_0.5Co_2.5O₄(LCO) is prepared by the sol–gel combustion approach and is used as an electrode for fabricating a high-performance supercapacitor. The characterization of the proposed material using the diffraction X-ray pattern shows the creation of a single-phase cubic spinel oxide structure. The scanning and transmission electron microscopy reveals that these spinel-type lithium cobalt oxide samples contain homogeneous nanocrystalline and uniform grains, while the magnetic investigation demonstrates the ferrimagnetic behavior. Furthermore, the electrochemical properties of the developed electrode are investigated using Cyclic Voltammetry (CV), Galvanostatic Charge Discharge (GCD), and Electrochemical Impedance Spectroscopy (EIS) studies in a 1 M KOH electrolyte. The synthesized material is discovered to have a specific capacitance of 2565.5F/g at a current density of 5 mA/cm² with a corresponding energy density of 57Wh/kg and power density of 476 W/kg. Moreover, the proposed electrode material demonstrates excellent capacitance retention well over 91.24 % even after 5000 GCD cycles. Hence, the result shows that the electrode Li_0.5Co_2.5O₄ is a potential candidate for supercapacitor application.