PALLADIUM ELECTRODEPOSITION ON ELECTROCHEMICALLY OXIDIZED CARBON-FIBERS AND ELECTROCATALYTIC ACTIVITY OF THE MODIFIED ELECTRODES

Palladium-modified carbon electrodes are prepared by electrodeposition of this noble metal after ion exchange of its cations with the hydrogen ions of the acidic groups of electrochemically oxidized carbon fibres. Electrooxidation of the fibres is achieved by repetitive anodic and cathodic pulse application. Through this procedure a large number of surface acidic groups is formed on the carbon fibres. The palladium-modified electrodes exhibit strong hydrogen adsorption peaks in H2SO4 and HClO4 solutions and show a high catalytic activity in the electrooxidation of formic acid, in the electroreduction of nitrobenzene and in the hydrogenation of benzoyl chloride and oleic acid.