ISBN 9783843915434

978-3-8439-1543-4, Reihe Theoretische Chemie

Christina Ebensperger
Chemical modification of transition metal oxide surfaces by gas phase molecules and liquid water

168 Seiten, Dissertation Universität Erlangen-Nürnberg (2014), Softcover, A5

Zusammenfassung / Abstract

Insights into atomistic processes of the interactions of molecules with surfaces are crucial for a better understanding of a large field of surface-related phenomena, for example in heterogeneous catalysis or in electrochemistry.

Two surfaces are studied in detail: The (111) surface of nickel oxide (NiO) in contact with different gas phases and the interface between the hydrated surface of a layered sodium titanium oxide with liquid water.

The bulk truncated polar NiO(111) surfaces is intrinsically unstable. Therefore, a wide range of competing stabilization mechanisms for the surface in contact with gas phases of different molecules, including surface reconstructions, hydroxylation or embedding of adsorbates, is examined. Apart from the thermodynamically stable structures, kinetic limitations are considered. The involved activation barriers stabilize metastable transition states which become accessible in experiment. This explains the wide range of described surface structures.

The second studied interface is sodium titanium hydrate in contact with liquid water. The bulk structure consists of negatively charged titanium oxide layers which are held together by intercalated sodium ions. In a water surrounding the topmost sodium ions dissolve and the surface is protonated. The detailed study of this solid-liquid interface reveals insights into the influence of a liquid on a surface, the organization of the liquid at the interface and in solid-liquid interactions like a water mediated surface proton transport.