| Abstract
| - Adsorption and decomposition of methanol on Au nanoclusters supported on an ordered ultrathin film ofAl2O3/NiAl(100) have been investigated by means of their photoelectron spectra excited with synchrotronradiation and scanning tunneling microscopy. The results show adsorption sites on the clusters of at least twotypes: one catalyzes the decomposition of methanol via scission of the O−H bond into CO at a temperatureas low as 120 K, whereas the other activates dehydrogenation only into methoxy. The CO from thedecomposition remains on the surface up to 250 K, begins to desorb above 250 K, and decomposes furtherinto elemental carbon around 350 K. All carbon species are removable from the surface at 450 K, a temperaturemuch lower than on other metals studied. Regarding effects of morphology of the clusters on the reactivity,smaller Au clusters, of height 1−2 atomic layers, exhibit inactivity toward the decomposition of methanol.
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