ACTIVE-SITES IN METHANOL OXIDATION ON CU(110) DETERMINED BY STM AND MOLECULAR-BEAM MEASUREMENTS

STM has been combined with molecular beam rate measurements to gain an understanding of the oxidative dehydrogenation of methanol to produce formaldehyde, both at the macroscopic and microscopic level. From thi s a model of the reaction is developed where the methanol initial reac ts at very few active oxygen sites located at the short sides of oxyge n islands on the Cu(110) surface. Such sites are very much rarer on a surface which is saturated with 0.5 monolayers of oxygen and the react ion rate is initially very low, but shows autocatalytic behaviour, ris ing in time as vacancies are created in the oxygen layer.