Berlin 2005 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
O: Oberflächenphysik
O 3: Oberfl
ächenreaktionen I
O 3.5: Vortrag
Freitag, 4. März 2005, 11:45–12:00, TU EB420
Interaction of Hydrogen with RuO2(110) Surfaces — •Yuemin Wang1,2, Jinhai Wang2, Chaoyang Fan2, Karl Jacobi2, and Gerhard Ertl2 — 1Lehrstuhl für Physikalische Chemie I, Ruhr-Universität Bochum — 2Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin
The adsorption and reaction of hydrogen on the stoichiometric and oxygen-rich RuO2(110) surfaces - the latter exposing a weakly bound atomic oxygen species (O-cus) on-top of the unsaturated Ru atom (Ru-cus) - was studied using high-resolution electron energy-loss spectroscopy (HREELS) and thermal desorption spectroscopy (TDS). On the stoichiometric RuO2(110) surface two hydrogen adsorption states are identified at 85 K [1]: Molecular hydrogen at Ru-cus and dissociated hydrogen forming a dihydride with O-bridge, the other unsaturated surface oxygen besides O-cus. The dihydride is transformed into monohydride by release of hydrogen at 350 K. On oxygen-rich RuO2(110) surfaces hydrogen reacts with O-cus forming H2O-cus. This species undergoes desorption instead of dissociation with heating to higher temperatures. The reaction mechanisms of hydrogen with O-bridge and O-cus are derived.
[1] Wang, J.; Fan, C. Y.; Sun, Q.; Reuter, K.; Jacobi, K.; Scheffler, M.; Ertl, G. Angew. Chem. Internat. Edition 2003, 42, 2151.