An Electrochemical Capacitor Electrode Based on Porous Carbon Spheres Hybrided with Polyaniline and Nanoscale Ruthenium Oxide

Abstract

Nanoscopic ruthenium oxide (RuO(2))/polyaniline (PANI)/carbon double-shelled hollow spheres (CS) composites, RuO(2)/PANI/CS, have been prepared via electro-polymerization of aniline and redox deposition of RuO(2) on the surface of CS. The structures and morphologies of the resulting ternary composites are characterized using scanning electron microscopy (SEM), infrared spectroscopy (IR), energy-dispersive X-ray spectroscopy (EDX). The electrochemical properties of the ternary composites as active electrode materials for electrochemical capacitors have been investigated by different electrochemical techniques including cyclic voltammetry, galvanostatic charge-discharge, and impedance spectroscopy. The results show that the specific capacitance of RuO(2)/PANI/CS composites is 531 F g(-1) at 1 mA cm(-2) in 1.0 M H(2)SO(4) electrolyte, which is higher than many other currently available ternary composites based on RuO(2)/PANI. At the same time, the composites display a good rate capability and 70% of the initial specific capacitance is retained with the charge-discharge current density up to 10 mA cm(-2).