Sequential electrodeposition of layered Co3O4/rGO/PANI ternary nanocomposite electrodes for high performance supercapacitors

Abstract

A layered Co₃O₄/rGO/PANI ternary nanocomposite was successfully synthesized via sequential hydrothermal and electrodeposition on a steel substrate. This stepwise approach fosters strong interfacial coupling and a well-organized electrochemical hierarchy, overcoming the limitations of individual components. The ternary electrode achieves a remarkable specific capacitance of 1650.35 F g⁻¹ (10 mV s⁻¹) and a high specific energy of 134.09 Wh kg⁻¹ in 1 M H₂SO₄, significantly exceeding the performance in neutral (0.5 M Na₂SO₄) and alkaline (2 M KOH) media. While Co₃O₄ thrives under alkaline conditions, the integrated composite benefits from the rapid kinetics of the acidic environment, delivering a superior balance of energy and power density (2996.06 W kkg⁻¹). These results demonstrate that the binder-free, layered architecture is a highly effective strategy for engineering advanced, high-capacity supercapacitor electrodes.