关键词: 石英晶体微天平, Pt电极, 修饰电极, 甲醇

Abstract: The processes of adsorption and oxidation of methanol on Pt, Pt/Sb ad and Pt/S ad electrodes were studied by using cyclic voltammetry and electrochemical quartz crystal microba_lance (EQCM). The results demonstrated that the oxidation of methanol depends strongly on oxidation states of electrode surface. Sb adatoms on Pt surface can adsorb oxygen at relatively low potentials, and exhibit catalytic effects for methanol oxidation. In contrast to Pt electrodes, the oxidation peak potential of methanol in this case negatively shifted to about 130 mV. In a contrary, the oxidation of S adatoms consumes oxygen species of Pt electrode surface. As a consequence, the oxidation of methanol was inhibited by the presence of S ad . The EQCM studies provided quantitative results of surface mass variation during methanol oxidation, and have thrown new light in elucidating different effects of adatoms Sb ad and S ad on Pt electrode surface towards methanol oxidation.

Key words: EQCM, Pt, Sb ad, S ad, Methanol