Hollow PdCu2@Pt core@shell nanoparticles with ordered intermetallic cores as efficient and durable oxygen reduction reaction electrocatalysts

Carbon-supported hollow PdCu2@Pt core@shell nanoparticles with ordered intermetallic cores were prepared as an efficient and durable oxygen reduction reaction (ORR) electrocatalyst for polymer electrolyte membrane fuel cells (PEMFCs). PdCu2 cores prepared using a chemical reduction method were thermally treated to produce ordered intermetallic structures. A Pt shell was then deposited via a galvanic displacement process. The effect of the galvanic displacement conditions on the properties and structure of the obtained core shell nanoparticles was investigated by varying the solution pH and anion concentration. Acidic conditions and low Cl- concentrations were found to provide a uniform Pt layer with a hollow core, while maintaining the ordered intermetallic core structure. These hollow PdCu2@Pt core@shell nanoparticles showed high activity and stability for ORR electrocatalysis in PEMFCs.