Polythiophene–RuO ₂ –Polyaniline Ternary Nanocomposite for High-Performance Supercapacitor Electrodes

A ternary polythiophene–RuO 2 –polyaniline (PTh–RuO 2 –PANI) nanocomposite was synthesized via in situ chemical oxidative polymerization using ammonium peroxydisulfate as the oxidant and evaluated as a high-performance supercapacitor electrode. Structural and surface analyses confirmed the successful formation of the ternary architecture and effective integration of RuO 2 within the conducting polymer network. The PTh–RuO 2 –PANI nanocomposite delivered a specific capacitance of 636 F g –1 at 1 A g –1 in a three-electrode configuration, outperforming the pristine and binary counterparts. A symmetric two-electrode device achieved specific capacitance of 484 F g –1 at 1 A g –1 with an energy density of 16.8 Wh kg –1 at a power density of 250 W kg –1 . The electrode retained 90.5% of its initial capacitance after 3000 cycles at 15 A g –1, demonstrating excellent cycling stability. Despite its relatively low surface area compared to binary and single-component counterparts, the ternary composite exhibits superior capacitance, indicating that charge storage is governed mainly by synergistic interfacial redox activity, improved charge-transfer kinetics, and nitrogen-containing functionalities from PANI rather than surface area alone. Overall, the results demonstrate that the PTh–RuO 2 –PANI ternary nanocomposite is a promising electrode material for high-performance supercapacitor applications.