The adsorption of alcohols on hydroxylated Si(100)-2x1

The adsorption of ethanol, isopropanol and tert-butanol on clean and H2O pre-dosed Si(100)-2 x 1 has been studied by high resolution electron energy loss spectroscopy (HREELS). We observe that the reactivity of the alcohols towards Sii 100)-2 x 1 pre saturated with H2O decreases with increasing number of methyl groups in the series (CH3)nCH(3-n)OH (n=1, 2, 3). All alcohols chemisorb on the silicon substrates via a deprotonation of the OH group with the formation of alkoxy and silicon hydride species. In the case of H2O saturated Si(100)-2 x 1. the adsorption involves cleavage of the Si-Si bond of the silicon surface dimer. (C) 1997 Elsevier Science B.V.