Enrich the competency of MnCo₂O₄ electrode exposed under air plasma to achieve superior coulombic efficiency in super capacitors

The study presents the synthesis and characterization of manganese cobalt oxide (MnCo₂O₄) nano particles for potential use as cathode materials in supercapacitors. The synthesis method employed is a cost-effective and environmentally friendly top-down solid-state approach. Phase purity is confirmed through X-ray diffraction (XRD) analysis post-calcination at 600 °C. Fourier transform infrared spectroscopy (FTIR) reveals notable metal oxide vibrational modes in the MnCo₂O₄. Raman analysis is utilized for structural characterization, while contact angle measurements assess material wettability. Morphological features are examined via field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), energy-dispersive X-ray spectroscopy (EDX), and elemental colour mapping. Introducing plasma treatment enhances material properties including intensity, bending vibrations, morphology, and capacitance, as demonstrated through galvanostatic charge-discharge tests (GCD). The resulting air plasma-treated MnCo₂O₄exhibits a significant capacitance of 897 F/g at 0.05 A/g in a 2 M KOH electrolyte, with long-term cyclic stability testing over 500 cycles revealing a calculated columbic efficiency of 90.15%. Overall, this study emphasizes the efficacy and simplicity of the method in producing MnCo₂O₄ nanomaterials, demonstrating their potential as electrode materials for supercapacitor applications.