Designing Efficient Catalysts through Bimetallic Architecture: Rh@Pt Nanocubes as a Case Study

Bimetallic nanocatalysts often have increased activities and stabilities over their monometallic counterparts due to surface strain effects and electron transfer between the two metals. Here, we demonstrate that the performance of a nanocatalyst can be precisely manipulated in shape-controlled nanocrystals through a bimetallic core@shell architecture. This ability is achieved in a model core@shell Rh@Pt nanocube system through control of shell thickness. The enhanced performance with thin-shelled nanocrystals is correlated with the weakening of surface-adsorbate interactions. In these thin-shelled Rh@Pt nanocubes, the maximum current density achieved during formic acid oxidation was over 2 times greater than that achieved with similarly sized Pt nanocubes, with a decreased CO poisoning ratio as well. The strategy employed here should also enhance the performance of many other bimetallic nanomaterials composed of more cost-effective metals too.