Controllable growth of palladium on gold multipod nanoparticles and their enhanced electrochemical oxygen reduction reaction performances

Abstract

Integration of two metal constituents into core–shell structures is an efficient strategy to prepare advanced materials for a variety of applications. The controllable synthesis of targeted bimetallic core–shell nanostructures is an important yet challenging task. Herein, bimetallic nanoparticles comprising a gold multipod nanoparticle (GMN) core and distinctive Pd shell (GMN@Pd NPs) are successfully synthesized in a facile and controllable manner. Epitaxial or islanded growth of Pd on the GMNs can be readily achieved using appropriate stabilizing agents. The controllable growth mode of the Pd layers, coupled with the unique topologies of GMNs, are advantageous for enhancing the density of active interfacial surfaces in the composites. Particularly, I-GMN@Pd NPs show substantially enhanced ORR activity compared with monometallic counterparts and excellent durability and better tolerance to the crossover effect than that of Pt/C, rendering the materials highly desirable for practical use.