Hydrothermal synthesis, characterization, and electrochemical behaviour of cobalt oxide (Co₃O₄) nanoparticles for stable electrode with enhanced supercapacitance

The electrochemical performance of highly crystalline cobalt oxide (Co₃O₄) nanoparticles is described in this work using an oxalate-assisted hydrothermal synthesis in the presence of a natural surfactant. The Co₃O₄ nanoparticle has a cubic spinel crystal structure with a crystallite size of 39 nm as determined XRD analysis. FTIR and UV–vis spectrum methods are used to evaluate the optical and functional properties of the synthesized Co₃O₄ nanoparticles. Due to the quantum confinement effect, the UV–vis spectrum of Co₃O₄ nanoparticles shows a wide energy band gap of 4.78 eV, which confirms the semiconducting nature of Co₃O₄ nanoparticles. The excellent performance is attributable to the simple accessibility of the electrolyte as well as the porous poly-pyramidal shape, which enables Co₃O₄ nanoparticles' volume expansion. In light of their charging and discharging behaviour, electrochemical examination of green chemical oxalate aided Co₃O₄ nanoparticles reveals remarkable super capacitance behaviour with rapid dissemination of electrolyte ions on the electrode. These findings discover that the hydrothermally synthesized Co₃O₄ nanoparticles are novel materials for making high-potential super capacitors. (author)