Morphology and activity tuning of Cu₃Pt/C ordered intermetallic nanoparticles by selective electrochemical dealloying.

Abstract

Improving the catalytic activity of Pt-based bimetallic nanoparticles is a key challenge in the application of proton-exchange membrane fuel cells. Electrochemical dealloying represents a powerful approach for tuning the surface structure and morphology of these catalyst nanoparticles. We present a comprehensive study of using electrochemical dealloying methods to control the morphology of ordered Cu3Pt/C intermetallic nanoparticles, which could dramatically affect their electrocatalytic activity for the oxygen reduction reaction (ORR). Depending on the electrochemical dealloying conditions, the nanoparticles with Pt-rich core-shell or porous structures were formed. We further demonstrate that the core-shell and porous morphologies can be combined to achieve the highest ORR activity. This strategy provides new guidelines for optimizing nanoparticles synthesis and improving electrocatalytic activity.