Carbon: Science and Technology (Dec 2009)
Electrochemical characterization of ruthenium oxide on carbon paste electrodes in acid system
Abstract
A comparative study of the electrochemical behavior of ruthenium in the electrolytic system 10-2 M RuCl3 /1 M HClO4 at pH=1 was carried out using carbon paste electrodes prepared with carbon black(nanostructurated). Measurements of absorbance in the region of visible spectrum showed that the electroactive species is an oxy aquocomplex. Studies of cyclic voltammetry of reversed potentials (Eλ) allowed for the description of the oxidation processes involved. The oxidation process explained the electrochemical formation of a ruthenium oxide (RuO4) which appeared with a defined potential value. This permitted its electrochemical growth on the paste electrodes. Capacitive behavior of this oxide in the system 1 M HClO4 was also characterized and its specific capacitance (F/g) was evaluated applying a current pulse. The obtained specific capacitance is of 120 Fg-1.
