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 bulkimmiscible nanoparticles with metastable randomly alloyed structures. In this study, we combine computational screening and a microwave-based synthesis method to target bulkimmiscible 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.