The Influence of Oxide Sol Properties on the Capacitive Behavior of Carbon Supported Hydrous Ruthenium Oxide

摘要

Carbon supported hydrous ruthenium oxide was prepared by an ultrasonic threatment of carbon black-RuO_xH_y sol mixture (impregnation). Black Pearl 2000~(~R) was used as a supporting material, while an oxide sol was prepared by forced hydrolysis of hydrous RuCl_3. The influence of the RuO_xH_y sol aging time and the amount of oxide solid phase in the impregnating medium on the capacitive behavior of prepared carbon supported hydrous ruthenium oxide was investigated by cyclic voltarnmetry and electrochemical impedance spectroscopy. The oxide amount in the composite increases with increasing concentration of oxide particles in the impregnating medium. The composite specific capacitance decreases with increasing aging time of oxide sol, while increases with increasing concentration of oxide particles in the impregnating medium. Transition line model fits well the composite impedance behavior indicating a distinctive capacitive response of the inner and the outer composite active surface. This distinction becomes more pronounced as the amount of oxide in the composite increases.