| AVS 57th International Symposium & Exhibition | |
| Surface Science | Thursday Sessions |
| Session SS-ThM |
| Session: | Adsorption and Reactivity on Oxide Surfaces |
| Presenter: | A. Gonchar, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Germany |
| Authors: | A. Gonchar, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Germany T. Risse, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Germany H.-J. Freund, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Germany |
| Correspondent: | Click to Email |
Theoretical calculations [1, 2] have predicted novel catalytic properties of ultra thin MgO films for CO oxidation. In particular, molecular oxygen is thought to be activated on ultra thin MgO films due to a charge transfer from the metal substrate resulting in the formation of paramagnetic O2-.
We have investigated the adsorption of O2 on ultra thin MgO(001) films grown on Mo(001) single crystals using in situ Electron Paramagnetic Resonance (EPR) spectroscopy. Adsorption of oxygen on 4 ML thick MgO(001) films creates an EPR signal associated with the formation of O2- radicals. The orientation of these radicals on the MgO surface is deduced from angular dependent EPR measurements. The properties of O2- radicals with respect to thermal stability and external parameters such as the film thickness will be discussed.
References
[1] A. Hellman, S. Klacar, and H. Grönbeck, JACS 2009, 131, 16636–16637
[2] P. Frondelius, H. Häkkinen, and K. Honkala, PCCP 2010, 12, 1483–1492