Adsorption and dissociation processes of water on tungsten trioxide (001) from first principles*

Photocatalytic water splitting is a cutting-edge topic nowadays since there is no environmental friendly and efficient way known for hydrogen production. A promising material in this context is tungsten trioxide, which has on the one hand a suitable band gap and an appropriate valence band position for oxygen production, but on the other hand an unsuitable conduction band position for hydrogen evolution [1].
At this point, a deeper understanding of the water splitting mechanism is crucial in order to make this reaction more efficient. Calculations with periodic boundary conditions offer a powerful tool regarding the modelling and understanding of adsorption processes and reactions on solid surfaces.
In this work, we present results of the interaction of water in its molecular and its dissociative form on the tungsten trioxide (001) surface. We used hybrid density functional theory as implemented in the CRYSTAL14 [2] program package. These results are useful in order to perform ab initio cluster calculations for ground and excited states.

[1] F. Wang, C. Di Valentina, G. Pacchioni, Phys. Chem. C 116, 8901-8909 (2012).
[2] R. Dovesi, R. Orlando, A. Erba, et al., Int. J. Quantum Chem. A 114, 1287-1317 (2014).