Concurrent adsorption of carbon monoxide and copper atoms on platinized platinum

In sulfuric acid solutions with carbon monoxide in contact with platinum co vered by a monolayer of copper atoms, at about 0.3 V, approximately 50% of copper atoms are forced off the surface and a mixed adlayer forms. Copper a toms form on about 30% of the surface of platinum, which is covered by a mo nolayer of COads and is in contact with a sulfate solution. Copper atoms ar e incorporated in the surface adlayer predominantly via the conversion of a bridge form of the CO adsorption into a linear form, rather than through t he forcing out COads. Possible reasons for the accelerating effect of Cu-ad on the CO electrooxidation are discussed.