Exploring the influence of KOH electrolyte concentration on the electrochemical properties of Co3O4-GO nanocomposite

Abstract

In this study, we investigate the electrochemical performance of Co3O4-GO nanocomposite, synthesized via a hydrothermal method, as a function of electrolyte concentration. XRD, Raman, SEM, TEM, XPS, and BET techniques have been employed to examine the structural, microstructural, chemical states, and specific surface area characteristics of the composite material. According to SEM micrographs, the aggregated particles have a sheet-like morphology, and these sheets have been assembled into clusters. Using N2-adsorption/desorption isotherms, the pore volume, diameter, and specific surface area of composite were determined to be 0.24 cm3/g, 15 nm, and 63 m2/g, respectively. Based on cyclic voltammograms (CVs) recorded at different scan rates and electrolyte concentrations, the working electrode demonstrated pseudocapacitance behavior. The specific capacitance (Cs) of the fabricated electrode was estimated from GCD curves recorded at different current densities and electrolyte concentrations. For 1 M KOH solution, Cs of the composite electrode is found to be 258 F/g at 1 A/g, and this value drops to 222 F/g at 5 A/g. Furthermore the composite electrode's Cs decreases with increasing electrolyte concentration at a specific current density. The study indicates that 1 M of KOH electrolyte is the optimal electrolyte concentration for optimal energy storage.