Pseudocapacitance characterization of hydrous ruthenium oxide prepared via cyclic voltammetric deposition

Hydrous ruthenium oxide (RuOx·nH2O) with average special capacitance of 105 F g−1 were directly prepared on titanium substrate by cyclic voltammetric (CV) deposition from an aqueous chloride solution in the −100 to 1000 mV range. Voltammertric responses studied by cyclic voltammograms as well as the charging and discharging behavior examined by chronopotentiometry in 1.0 M H2SO4 demonstrated high redox reversibility and obvious pseudocapacitance characterization of RuOx·nH2O for application in electrochemical capacitors. X-ray diffraction spectra exhibited an amorphous structure of this hydrous oxide. The deposited oxides, consisted of mixed oxyruthenium species, with various oxidation states are demonstrated by X-ray photoelectron spectroscopy. The RuOx·nH2O morphologies are uniform and compact after 60 growth cycles demonstrated.