CO Oxidation over Strained Pt(100) Surface: A DFT Study

Abstract

The oxidation of CO on strained Pt(100) surface was studied using periodic density functional theory (DFT). Unlike the uniform response of global properties (e.g., d-band center) to strain, the localized nature of adsorption leads to complex site-dependent and adsorbate-dependent responses, invalidating the generally believed statement of “tension strengthens binding”. Moreover, the complex responses of reaction energetics to strain require direct study of the reaction under strain rather than extrapolating the known behaviors of individual adsorbates under strain or reaction energetics on unstrained surfaces. We show that the tensile strain lowers the reaction barrier of CO oxidation over the Pt(100) surface. This work provides a theoretical basis of utilizing strain to improve the Pt catalysts with a higher tolerance toward CO poisoning.