Effects of electron transfer in model catalysts composed of Pt nanoparticles on CeO2(1Â 1Â 1) surface

- ∼1.5 nm particles forming Pt122{1 1 1}||CeO2(1 1 1) and Pt95{1 0 0}||CeO2(1 1 1) interfaces.
- Simulation approach enabling full control of electron transfer in model catalysts.
- Interaction of Pt particles with CeO2(1 1 1) shifts d-states of Pt to lower energies.
- Pt-ceria interaction increases average Pt-Pt distances in the supported particles.
- Geometry and DOS of the Pt particles are slightly altered by the electron transfer.

Interactions between transition metal nanoparticles and reducible oxide supports are thought to significantly affect the performance of many catalysts. Usually, several metal-support effects act together and cannot be separated from each other. Herein, by means of density-functional calculations we succeeded to single out and quantify effects of the metal-support electron transfer on the structure and electronic properties of important model Pt-ceria catalysts. Namely, we considered ∼1.5 nm large Pt95 and Pt122 particles supported on CeO2(1 1 1). We show that Pt-ceria interactions notably reconstruct Pt nanofacets forming the interface and shift valence d-states of the Pt particles. These effects are rather insensitive to the Pt-ceria electron transfer, at variance with the electronic structure of oxygen anions at the interface, which is significantly affected by the electron transfer. The findings of this work and the special modeling approach applied pave the way for deeper analysis of electronic metal-support interactions in catalysis.

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