Applicability of the d-Band Model to Predict the Influence of Elastic Strains on the Adsorption Energy of Different Adsorbates onto Pt and PtO 2 Surfaces.

The influence of elastic strains on the adsorption processes of seven adsorbates (H, C, N, O, CO, NO, and H) onto the surface of Pt(111) and PtO 2 (110) has been investigated using density functional theory (DFT) simulations. The total adsorption energy was decomposed into mechanical and electronic contributions. Our results indicate that elastic strain in metals affects the adsorption energy by modifying the electronic structure of the surface rather than changing the physical space where the atoms reside after adsorption. In fact, the mechanical contribution to the adsorption energy in Pt was negligible compared to the electronic interaction and independent of the deformation. The mechanical contribution in the case of PtO 2 was also independent of the applied strain, but its magnitude was slightly higher due to the ionic bonding between Pt and O atoms in the slab. The variation of the electronic contribution to the adsorption energy in Pt and PtO 2 followed the predictions of the d-band model for all adsorbates, expanding its applicability to different adsorbates onto the same surface and to oxides.