-Anatase(101): Insights from Periodic Slab and Embedded Cluster Calculations*

The efficient splitting of water nowadays represents one of the major scientific challenges.[1] To further progress within this research field, an understanding of the elementary mechanisms is crucial.

The initial step of this reaction comprises the adsorption of a water molecule on the catalyst's surface. As a model system, we utilize the titania-anatase (101) surface. This modification is well known for its enhanced photocatalytic activity compared to the TiO₂-rutile phase [2] and it is furthermore applied as a protective layer for photoanodes.[3]

We use periodic slab calculations based on the GTO-LCAO approach and density functional theory to characterize the adsorption sites and surface behavior. These results constitute the basis for an embedded cluster approach, that allows for a precise calculation of the energetics of the adsorption process using post-HF methods.

[1] L. M. Peter, K. G. U. Wijayantha, ChemPhysChem 15, 1983 (2014).
[2] V. Etacheri, C. Di Valentin, J. Schneider, et al., J. Photochem. Photobiol. C: Photochem. Rev. 25, 1 (2015)
[3] B. Mei, T. Pedersen, P. Malacrida, et al., J. Phys. Chem. C 119, 15019 (2015).