CATALYTIC INFLUENCE OF UNDERPOTENTIALLY DEPOSITED SUBMONOLAYERS OF DIFFERENT METALS IN ETHYLENE-GLYCOL OXIDATION ON VARIOUS NOBLE-METAL ELECTRODES IN ALKALINE-MEDIUM

The electrochemical oxidation of ethylene glycol has been studied on P t, Pd and Au electrodes in alkaline medium in the absence and in the p resence of metal ad-atoms. For pure-metal electrodes, the maximum curr ent density was obtained at an Au electrode. However, in the presence of metal ad-atoms, enhancement of catalytic activity changes its order to: Pt > Au > Pd. The three different electrodes exhibit maximum cata lytic activity when modified with Pb ad-atoms. The decreasing order of enhancement by ad-atoms under investigation is: Pb > Bi > Tl > Sn > C d.