SYNTHESIS AND CHARACTERIZATION OF RuO2/POLY (3,4- ETHYLENEDIOXYTHIOPHENE) (PEDOT) COMPOSITE NANOTUBES FOR SUPERCAPACITORS

We report the synthesis of composite RuO2/(3,4-ethylenedioxythiophene) (PEDOT) nanotubes with high specific capacitance and fast charging/discharging capability as well as their potential application to the electrode materials for a high-energized and high-powered supercapacitor. We show that the energy density (specific capacitance) of PEDOT nanotubes can be remarkably enhanced by electrodepositing RuO2 into their porous walls and onto their rough internal surfaces. The flexible PEDOT prevents the RuO2 from breaking while the rigid RuO2 keeps the PEDOT nanotubes from collapsing and aggregating. The composite RuO2/PEDOT nanotube can reach a high power density of 20 kW/kg while maintaining 80% of its energy density (28 Wh/kg). This high power capability is attributed to the fast charge/discharge of nanotubular structures. The high energy density is benefited from the RuO2, of which the high specific capacitance (1217 F/g) is realized owing to its high specific surface area brought by the nanotubular structures.