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Support-mediated activation and deactivation of Pt thin films

Valentino R. Cooper·Alexie M. Kolpak·Yashar Yourdshahyan·Andrew M. Rappe
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Abstract

Using ab initio methods, we examine the the charge distribution at the interface of alpha-alumina-supported Pt films, and we consider the influence of this interface on CO adsorption. We demonstrate that a combination of electrostatic charge transfer and covalent bonding governs the interfacial interactions, and that these interactions play an important role in the metal reactivity. By modifying the interface and varying the Pt film thickness over a nanoscale range, CO adsorption can be significantly enhanced or diminished. These observations could be used to tune the reactivity of Pt particles.

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Valentino R. Cooper, Alexie M. Kolpak, Yashar Yourdshahyan, Andrew M. Rappe. 2004-10-14. Support-mediated activation and deactivation of Pt thin films. https://doi.org/10.1103/physrevb.72.081409

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