Ternary MnCo2O4/MWCNT/rGO nanocomposites as high-performance supercapacitor electrode materials

In this research, MnCo2O4 nanoparticles and their composites with reduced graphene oxide (rGO), multi-wall carbon nanotube (MWCNT), and MWCNT/rGO were synthesized by a simple hydrothermal method to investigate their performance as supercapacitor electrodes. The crystal structure and morphology of the fabricated materials were studied through X-ray diffraction, field-emission scanning electron microscopy, and transmission electron microscopy. Moreover, electrodes of the samples were prepared by the hydrothermal method to investigate electrochemical properties. Cyclic voltammetry, galvanostatic charge-discharge (GCD), electrochemical impedance spectroscopy, and cyclic stability showed that the MnCo2O4/MWCNT/rGO composite with a high specific capacitance of 3346.6 F g-1 at the current density of 1 A g-1 had the highest capacitance and stability among all samples. The MnCo2O4/MWCNT/rGO electrode remained stable and preserved 91.18% of initial capacitance at the end of 10,000 cycles at the current density of 20 A g-1. This electrode, with a specific surface area of 45.9 m2 g-1 and suitable electrochemistry, has promise as an excellent electrode material for storing energy.