Dissociation and oxidation of methanol on Cu(1 1 0)

We have studied the dissociation and oxidation of methanol on the pure and oxygen-precovered Cu(1 1 0) surface using high resolution X-ray photoelectron spectroscopy (HRXPS) which allows the identification and quantification of reaction intermediates after various annealing steps while they are still on the surface. At 100 K methanol adsorbs molecularly on the clean Cu(1 1 0) surface. Successive annealing causes dissociation into methoxy and formaldehyde around 200 K before eventually all molecular species desorb from the surface. On the oxygen-precovered surface (0.25 ML O) methanol is oxidized on the expense of the preadsorbed oxygen. The analysis of the HRXPS data shows that there are at least three intermediate molecular species present on the surface, most likely methoxy, formaldehyde, and formate.