| AVS 54th International Symposium | |
| Surface Science | Monday Sessions |
| Session SS1-MoA |
| Session: | Water-Surface Interactions |
| Presenter: | T.K. Shimizu, Lawrence Berkeley National Laboratory |
| Authors: | T.K. Shimizu, Lawrence Berkeley National Laboratory A. Mugarza, Lawrence Berkeley National Laboratory P. Cabrera-Sanfelix, Donostia International Physics Center, Spain D.S. Portal, Unidad de Física de Materiales, Centro Mixto CSIC-UPV, Spain A. Arnau, Departamento de Física de Materiales UPV/EHU, Spain D.F. Ogletree, Lawrence Berkeley National Laboratory M. Salmeron, Lawrence Berkeley National Laboratory |
| Correspondent: | Click to Email |
The adsorption of water on a Ru(0001) surface pre-covered with atomic oxygen forming a (2x2) structure was studied using low temperature scanning tunneling microscopy (STM). Below 0.25 ML, water adsorbs molecularly on top Ru sites within the (2x2) superstructure and forms two hydrogen bonds with pre-adsorbed O atoms. Because of the additional H-bonding, the water molecules are more strongly bound than those on the bare Ru metal. Water dissociation is completely blocked on the (2x2)-O/Ru surface and annealing results only in molecular desorption in the temperature range of 140-230 K. This is in contrast to the water adsorption on Ru with smaller pre-coverage of oxygen. These results will be discussed in light of current models relating water binding to the hydrophillicity and hydrophobicity of the underlying metal surfaces.