Preparation and characterization of electro-spun RuO2-Ag2O composite nanowires for electrochemical capacitors

We synthesized RuO2-Ag2O composite nanowires by means of an electrospinning method and investigated the capacitance, high-rate performance, and cycle number dependence of the composite nanowire electrodes. In order to synthesize optimum RuO2-Ag2O composite nanowires, the relative mole ratio of Ag precursor to Ru precursor varied from similar to 0.1 to similar to 0.3. X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and high-resolution transmission electron microscopy results show that crystalline RuO2-Ag2O composite nanowires (similar to 40-70 nm in diameter) are formed upon calcinations. Cyclic voltammetry results show that among the samples, the RuO2-Ag2O composite nanowires fabricated with the mole ratio of similar to 0.2 give the highest capacitance, excellent high-rate performance, and excellent retention of capacity (similar to 97%). (C) 2011 Elsevier B.V. All rights reserved.