Abstract
The adsorption of water on the anatase TiO2(001)-(4 x 1) surface is studied using synchrotron radiation-excited core level photoelectron spectroscopy. The coverage-dependent adsorption of water at low temperature is monitored and compared to the sequence obtained after heating of a water multilayer. Two adsorption phases of submonolayer coverage can be defined: Phase 1 consists only of dissociated water, observed as OH-groups. This phase is found at low coverage at low temperature (190 K) and is the only state of adsorbed water above similar to 230 K. The saturation coverage of phase 1 is consistent with dissociation on the 4-fold-coordinated Ti ridge atoms of the (4 x 1) surface reconstruction. Phase 2 is found at higher coverage, reached at lower temperature. It consists of a mixture of dissociated and molecular water with a ratio of 1:1 at 170 K. The molecular water is found to bond to the hydroxyl groups. The hydroxyl coverage of phase 2 is approximately 2 times that of phase 1. The results suggest that the OH and H2O species of phase 2 are confined to the ridges of the surface.
Original language | English |
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Pages (from-to) | 16616-16621 |
Journal | Journal of Physical Chemistry C |
Volume | 112 |
Issue number | 42 |
DOIs | |
Publication status | Published - 2008 |
Bibliographical note
The information about affiliations in this record was updated in December 2015.The record was previously connected to the following departments: Chemical Physics (S) (011001060)
Subject classification (UKÄ)
- Atom and Molecular Physics and Optics