Highly efficient and stable nonplatinum anode catalyst with Au@Pd core–shell nanostructures for methanol electrooxidation

Abstract

This paper reports the easy synthesis of Au@Pd core–shell nanoparticles (NPs) with uniform shell thickness and demonstrates their viability as a nonplatinum catalyst for the electrooxidation of methanol in alkaline anion-exchange membrane fuel cells. The synthesis involves the first preparation of Au core NPs, followed by a three-phase-transfer procedure to coat Pd shells, through which homogeneous Pd shell growth on Au cores can be achieved. The as-prepared Au@Pd NPs have an activity more than 40 times higher than that of the Pd catalyst for the methanol oxidation. Moreover, these Au@Pd NPs possess excellent stability (over seven times more stable than Pd catalysts). The remarkable performance enhancement is mainly attributed to the finely tailored electronic structure of the Pd shell achieved by the underlying Au core. The easily synthesized Au@Pd core–shell NPs represent a promising class of nonplatinum anode catalysts with high activity and durability for alkaline fuel cell applications.