Scalable Nanoporous (Pt_1-xNi_x)₃Al Intermetallic Compounds as Highly Active and Stable Catalysts for Oxygen...

Author: Bimetallic platinum-nickel (Pt-Ni) alloys as oxygen reduction reaction (ORR) electrocatalysts show genuine potential to boost widespread use of low-temperature fuel cells in vehicles by virtue of their high catalytic activity. However, their practical implementation encounters primary challenges in structural and catalytic durability caused by the low formation heat of Pt-Ni alloys. Here, we report nanoporous (NP) (Pt_1-xNi_x)₃Al intermetallic nanoparticles as oxygen electroreduction catalyst NP (Pt_1-xNi_x)₃Al, which circumvents this problem by making use of the extraordinarily negative formation heats of Pt-Al and Ni-Al bonds. The NP (Pt_1-xNi_x)₃Al nanocatalyst, which is mass-produced by alloying/dealloying and mechanical crushing technologies, exhibits specific activity of 3.6 mA cm^-2_Pt and mass activity of 2.4 A mg^-1_Pt at 0.90 V as a result of both ligand and compressive strain effects, while strong Ni-Al and Pt-Al bonds ensure their exceptional durability by alleviating evolution of Pt, Ni, and Al components and dissolutions of Ni and Al atoms.