The electrocatalytic performance of Ti/PbO₂ electrode was investigated during the electrochemical oxidation of phenol in H₂SO₄ solution by cyclic voltammetry. The results have shown that Ti/PbO₂ electrode have strong oxidation properties for phenol in H₂SO₄ solution. In a low initial concentration of phenol, phenol can be oxidized by adsorbed hydroxy radicals generated on electrode and finally mineralized. In a higher concentration phenol or little adsorbed hydroxy radicals generated, phenol and its intermediates may be adhesive to the electrode surface, consequently diminishes the electrochemical active surface area of electrode leading to the decrease of active sites, prevents the reactants from approaching the electrode surface and inhibits the further oxidation of phenol. With the increase of electrolysis time, the electrode activity can be restored due to the gradual oxidation of the substances adsorbed on electrode surface.

Key words: phenol, cyclic voltammetry, Ti/PbO₂ electrode, electrochemical oxidation