A nanocrystalline Co3O4@polypyrrole/MWCNT hybrid nanocomposite for high performance electrochemical supercapacitors

Abstract

In this study, a ternary hybrid nanocomposite of Co3O4@polypyrrole/MWCNT was prepared via oxidative polymerization of pyrrole monomer and a hybrid composite by a hydrothermal process. The synthesized hybrid nanocomposite was characterized by Raman spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy-EDX (SEM-EDX), and field emission resolution transmission electron microscopy (FE-TEM). The results of the structural and morphological studies of the hybrid nanocomposite show its controlled morphology and thermal stability. In addition, the electrochemical performances of charge-discharge cycles and impedance results were evaluated by cyclic voltammetry (CV) analysis. The as-synthesized hybrid nanocomposite was used to fabricate a three-electrode system in the presence of an electrochemical cell with 6 M potassium hydroxide (KOH) as electrolyte. The electrochemical performance of the hybrid composite displays good capacitive behavior with a specific capacitance of 609 F g-1 at a current density of 3 A g-1, energy density 84.58 (W h kg-1), power density 1500 (W kg-1), and a good specific capacitance retention of ca. 97.1% after 5000 continuous charge-discharge cycles, indicating that the hybrid nanocomposite can be a promising electroactive material for supercapacitors.