(327d) Face-Centered Tetragonal Pt Alloys of Fe & Co As Potential Catalysts for ORR
In this study, we investigate special face-centered tetragonal (L10) FePt and CoPt alloys in a core-shell geometry as a potential catalyst for oxygen-reduction reactions via both dissociative and associative mechanism using density functional theory. The effect on ORR activity as a function of strain, ligand and number of Pt overlayers is studied with the help of binding energies of the reaction intermediates and full free energy landscape . A mechanistic eigenstress and eigenstrain model is used to understand the binding of a reaction intermediate as a function of strain. The ORR activity is further compared with that of Pt(111) surface.
We further show the that L10-FePt and L10-CoPt show higher bulk and surface stability than the native Pt. To enhance the stability of the Pt alloys, we look into the role of core-shell structure on surface stability as a function of Pt overlayers.