Performance and stability of Pd-Pt-Ni nanoalloy electrocatalysts in proton exchange membrane fuel cells

▶ The Pd-Pt-Ni catalyst shows an improved Pt-mass activity twice of that of commercial Pt. ▶ The Pd-Pt-Ni catalyst shows stability within 200 h comparable to commercial Pt. ▶ Formation of a Pd-rich core-Pt-rich shell structure results in catalytic activity enhancement. ▶ Redeposition of Pd ions in MEA and ion-exchange of Ni ions in Nafion may lead to contamination.