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U. Diebold:
"Organic Molecules at Oxide Surfaces";
Vortrag: Vortrag im Rahmen der Chemisch-Physikalischen Gesellschaft, Fakultät für Physik, Universität Wien; 22.03.2011.

We have studied the adsorption of a variety of aromatic organic molecules on TiO2 rutile (110) and anatase (101) surfaces using a combination of STM, photoemission spectroscopy, and accompanying DFT calculations performed by collaborators.
We have found that the electronic structure of catechol (C6H4(OH)2) is intimately related to its bonding configuration. In particular, a bi-dentate species induces a gap state on rutile (110), while the monodentate species does not [1]. The molecule switches back-and-forth between a bidendate and monodentate state via facile transfer of hydrogen transfer to and from the TiO2 surface. Hydrogen also plays a key role in the diffusion of catecholates across the surface [2].
We have also investigated the adsorption of aniline (C6H5NH2) and azobenzene (C6H5N=NH5C6) with the goal to better understand the role of TiO2 in the catalytic synthesis of nitroaromatics. We found that both molecules form the same superstructure on rutile (110) as well as anatase (101) surfaces, suggesting that TiO2 is instrumental in cleaving the N=N double bond of azobenzene.
A short overview of ongoing and planned experiments on other oxide surface will also be presented.
[1] S.-C. Li et al., JACS 131 (2009) 980 - 984
[2] S.-C. Li et al., Science 328 (2010) 882 - 884
[3] S.-C. Li and U. Diebold, JACS 132 (2010) 64 - 66