Rational Design of Pt3Ni Surface Structures for the Oxygen Reduction Reaction

A cluster expansion approach has been used to investigate the relationship between surface structures of Pt3Ni alloy catalysts and their catalytic activity. With the help of this approach, we have constructed a direct bridge between the atomic structure and catalytic properties of Pt-Ni catalysts at a variety of compositions and chemical environments. We predict that Pt3Ni(111) surfaces have substantial subsurface disorder, and as a result, the ORR activity of different surface sites varies by approximately 3 orders of magnitude. Using this model, we identify a Pt3Ni(111) surface with a multilayer Pt skin that is predicted to maximize catalytic activity and predict the conditions under which a Pt3Ni surface should be synthesized to realize high catalytic activity.