Parts | Days | Selection | Search | Updates | Downloads | Help
O: Fachverband Oberflächenphysik
O 60: Poster Session IV (Solid/liquid interfaces; Semiconductors; Oxides and insulators; Graphene; Plasmonics and nanooptics; Electronic Structure; Surface chemical reactions; Heterogeneous catalysis)
O 60.23: Poster
Wednesday, March 16, 2011, 17:30–21:00, P4
The chemisorption of hydrogen molecules on CaO films — •Sebastian Dahle1, Henning Munkert1,2, and Wolfgang Maus-Friedrichs1,3 — 1Institut für Physik und Physikalische Technologien, TU Clausthal, Leibnizstr. 4, 38678 Clausthal-Zellerfeld, Germany — 2Institut für Metallurgie, TU Clausthal, Robert-Koch-Str. 42, 38678 Clausthal-Zellerfeld, Germany — 3Clausthaler Zentrum für Materialtechnik, TU Clausthal, Leibnizstr. 4, 38678 Clausthal-Zellerfeld, Germany
The oxide and hydroxide species of Calcium and the underlying reaction processes are of great technological interest. Even the hydration of burnt limestone is just barely predictable. Our investigations start with the preparation of the Calcium oxide and hydroxide species in a clean ultra high vacuum (UHV) environment. During the development of in-vacuo preparation methods of Calcium hydroxide, the adsorption of hydrogen molecules has been investigated. We have found that hydrogen leads to the formation of hydroxide groups, which appears to be unlikely due to thermodynamics at the first glance. Furthermore, hydrogen apparently acts as catalyst for the hydroxidation of a complete Calcium oxide film through water impinging on the surface out of the residual gas. These effects have been studied with Metastable Induced Electron Spectroscopy (MIES), Ultraviolet Photoelectron Spectroscopy (UPS) and X-ray Photoelectron Spectroscopy (XPS).