Oxygen Reduction Reaction on Classically Immiscible Bimetallics: A Case Study of RhAu

The catalytic properties of bulk-immiscible alloys are less explored than their bulk-miscible counterparts due to inherent difficulties in their synthesis and stabilization. The development of alternative synthetic methods can, however, provide routes toward bulk-immiscible nanoparticles with metastable randomly alloyed structures. In this study, we combine computational screening and a microwave-based synthesis method to target bulk-immiscible alloys that show enhanced reactivity over pure metals for the oxygen reduction reaction (ORR). A number of systems are identified theoretically as promising ORR catalysts. The theoretical predictions are experimentally verified for the RhAu system, for which a specific surface ensemble is identified as being highly active in the ORR.