| AVS 54th International Symposium | |
| Surface Science | Tuesday Sessions |
| Session SS2-TuA |
| Session: | Excitations at Surfaces |
| Presenter: | N.G. Petrik, Pacific Northwest National Laboratory |
| Authors: | N.G. Petrik, Pacific Northwest National Laboratory C.D. Lane, Georgia Institute of Technology T.M. Orlando, Georgia Institute of Technology G.A. Kimmel, Pacific Northwest National Laboratory |
| Correspondent: | Click to Email |
The electron-stimulated desorption of molecular water from TiO2 (110) surface was investigated as function of coverage (0-5 ML), incident electron energy (5-100 eV), and other parameters. The two main water adsorption sites - 5-fold coordinated Ti4+ ions and bridge-bonded oxygens (BBO)- have significantly different cross-sections for electron-stimulated desorption, but similar cross-sections for electron-stimulated dissociation. Isotopic layering experiments show that both desorption and dissociation of water adsorbed on the Ti4+ sites is suppressed by deposition of water molecules on the BBO sites. The results suggest that electronic excitations in water molecules adsorbed on the Ti4+ sites can produce reactions (desorption or dissociation) in water molecules on the BBO sites. The experimental observations are discussed in terms of specific structural characteristics of thin water films on TiO2 (110).