Abstract
Proton exchange membrane fuel cells (PEMFCs) are lightweight, sustainable, and clean power sources that offer much promise for renewable energy applications. Nanostructured platinum (Pt) is the essential catalyst component to catalyze the oxygen reduction reaction (ORR) in PEMFCs. To address the Pt abundance issue and to enhance Pt catalysis, Pt is often alloyed with a transition metal (M) (M = Fe, Ni, Co, and so forth). Despite some impressive ORR activities demonstrated on MPt so far, the stabilization of M in the MPt alloy remains challenging in the oxidizing and acidic ORR condition. Here we report hard-magnet core/shell L10-CoPt/Pt nanoparticles as a highly active and durable catalyst for the ORR in fuel cells. Its catalytic performance surpasses the activity and durability targets set by the US Department of Energy. L10-CoPt/Pt is a practical catalyst for use in PEMFCs.
