Sequential Electrodeposition of Layered Co3O4/rGO/PANI Ternary nanocomposite Electrodes for High performance Supercapacitors

Abstract

A layered cobalt oxide, reduced graphene oxide and polyaniline (Co3O4/rGO/PANI) ternary nanocomposite thin film was successfully developed through sequential hydrothermal and electrodeposition approach on a steel substrate. The stepwise deposition process enabled strong interfacial coupling among the metal oxide, carbonaceous layer and conducting polymer, resulting in a uniform and adherent nanocomposite coating. Electrochemical investigations reveal that the Co3O4/rGO/PANI composite demonstrates a remarkable specific capacitance (Cs) of 1650.35 F g-1 at a scan rate of 10 mV g-1 in 1 M H2SO4, outperforming its capacitance in 0.5 M Na2SO4 (1526.58 F g-1) and surpassing binary Co3O4/rGO as well as the pristine individual components. Comparative analysis across three electrolytes (1 M H2SO4, 0.5 M Na2SO4, and 2 M KOH) shows that Co3O4 alone exhibits enhanced performance in alkaline media, while the ternary composite benefits most from the highly conductive acidic environment. The results demonstrate a highly effective strategy for designing advanced electrode materials by integrating transition metal oxides, carbon materials, and conductive polymers in a layered architecture, thus providing a promising pathway for developing high-performance supercapacitor electrodes with enhanced charge storage capability