Supercapacitive properties of hydrous ruthenium oxide/multi-walled carbon nanotubes nanocomposite

The ruthenium oxide-multiwalled carbon nanotubes composite (Ru-MWNTs) has been formed by ultrasonic synthesis process. The composite material was obtained by mixing aqueous solution of RuCl3 center dot 3H(2)O, active carbon and NaHCO3 under ultrasonic and heat treatment at 150 degrees C for 15 h. The Ru-MWNTs was characterized by XRD,TEM, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The results indicate that hydrous ruthenium oxide particles in an amorphous phase were deposited homogeneously on MWNTs. The composite electrode material has good super-capacitive behaviors in 1.0 mol center dot L-1 H2SO4 electrolyte. The specific capacitance MWNTs electrode is 15.5 F center dot g(-1). The specific capacitance of the composite is 100 F center dot g(-1), which is four times higher than that of MWNTs. Electrochemical impedance spectroscopy results exhibit that the porous structure of the composite facilitates penetration of electrolyte and the rate capability is enhanced by introduction of hydrous ruthenium oxide.