THE BONDING OF DIETHYL-ETHER, ETHANOL AND THEIR FLUORINATED ANALOGS TO ZIRCONIUM-OXIDE THIN-FILMS

We report a thermal desorption study of the interaction of water, diethyl ether, ethanol, perfluorodiethyl ether, and 2,2,2-trifluoroethanol with zirconium oxide thin films epitaxially grown on Pt(111) single-crystal surfaces, and with the Pt(111) metal surface for comparison. We find that water and the hydrogenated ether interact chemically with the oxide surface through the O lone pair, whereas the fluorinated ether has only a van der Waals interaction. Ethanol and 2,2,2-trifluoroethanol are decomposed to some extent on zirconium oxide upon heating. Fluorination decreases the bond strength between the molecules and the oxide surface. A similar trend is observed on the Pt(111) surface with regard to relative adsorptivity and reactivity of the adsorbates examined. Although the Pt(111) surface provides weaker interaction with the molecules that interact via O lone pair orbitals (water, ether and alcohol) than the oxide surface, it decomposes diethyl ether as well as the alcohols.