[Zurück]

J. Balajka, M. Hines, W. DeBenedetti, J. Pavelec, M. Schmid, U. Diebold:
"TiO₂(110) in Liquid Water, Air, and Solution";
Poster: DPG-Frühjahrstagung (DPG Spring Meeting) of the Surface Science Division, SurfaceScience21, virtual; 01.03.2021.

Our understanding of metal oxide surface chemistry arises from studies under highly idealized ultrahigh vacuum (UHV) conditions, that cannot be extrapolated to the complex reaction environments of real industrial processes. Material properties, such as chemical reactivity, are determined by the nature of individual surface sites and thus related to the detailed atomic configuration. Yet, the interfacial structure under application conditions remains largely unexplored.

I will review our work on the prototypical TiO2(110) surface in ambient and aqueous environments. Using a UHV-compatible dispenser of ultrapure liquid water, we demonstrated that the TiO2(110) surface is not altered upon contact with clean liquid water. However, when exposed to air, low-concentration atmospheric species, such as carboxylic acids, adsorb with high affinity and form an ordered overlayer at the surface, effectively passivating the undercoordinated Ti surface sites.[1]

I will further discuss a chemical functionalization of the TiO2(110) surface by a monolayer of terephthalic acid (1,4-benzenedicarboxylic acid) deposited from solution and intended to serve as a growth template for three-dimensional metal-organic networks (MOFs).