PtPb/PtNi Intermetallic Core/Atomic Layer Shell Octahedra for Efficient Oxygen Reduction Electrocatalysis.

Although explosive studies on pursuing high-performance Pt-based nanomaterials for fuel cell reactions have been carried out, the combined controls of surface composition, exposed facet, and interior structure of the catalyst remains a formidable challenge. We demonstrate herein a facile chemical approach to realize a new class of intermetallic Pt-Pb-Ni octahedra for the first time. Those nanostructures with unique intermetallic core, active surface composition, and the exposed facet enhance oxygen reduction electrocatalysis with the optimized PtPbNi octahedra exhibiting superior specific and mass activities (5.16 mA/cm and 1.92 A/mg) for oxygen reduction reaction (ORR) that are ∼20 and ∼11 times higher than the commercial Pt/C, respectively. Moreover, the PtPbNi octahedra can endure at least 15 000 cycles with negligible activity decay, showing a new class of Pt-based electrocatalysts with enhanced performance for fuel cells and beyond.