A Density Functional Theory Study of Self-Regenerating Catalysts LaFe1-xMxO3-y (M = Pd, Rh, Pt)

Periodic density functional theory was used to investigate the stability and electronic structures of precious-metal atoms in the vicinity of LaFe1-xMxO3 (M = Pd, Rh, Pt) perovsldte catalyst surfaces. It was found that the surface segregation of Pd and Pt is significantly stabilized by the introduction of O vacancies, whereas the solid-solution phase is favorable for Rh, suggesting an important role of 0 vacancies in the self-regeneration of Pd and Pt. On the basis of the results, we propose a possible Scenario for the self-regeneration of the precious metal in the perovskite catalyst.