Design of Pt-shell nanoparticles with alloy cores for the oxygen reduction reaction.

We report that the oxygen binding energy of alloy-core@Pt nanoparticles can be linearly tuned by varying the alloy-core composition. Using this tuning mechanism, we are able to predict optimal compositions for different alloy-core@Pt nanoparticles. Subsequent electrochemical measurements of ORR activities of AuPd@Pt dendrimer-encapsulated nanoparticles (DENs) are in a good agreement with the theoretical prediction that the peak of activity is achieved for a 28% Au/72% Pd alloy core supporting a Pt shell. Importantly, these findings represent an unusual case of first-principles theory leading to nearly perfect agreement with experimental results.