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DOE OSTI · 3682486

Hierarchical low Pt-loading “core-shell” electrocatalysts for the oxygen reduction reaction in fuel cells

Pagot, Gioele [University of Padova, Italy]·Vezzu, Keti [University of Padova, Italy]·Nale, Angeloclaudio [University of Padova, Italy]·Bonaccorso, Francesco [Istituto Italiano di Technilogia]·Kulesza, Pawel [Istituto Italiano di Tecnologia,]·Rutkowska, Iwona [Istituto Italiano di Tecnologia,]·Negro, Enrico [University of Padova, Italy]·Zawodzinski, Thomas [University of Tennessee, Knoxville (UTK)]·Cullen, David [ORNL] (ORCID:0000000225937866)·Zelenay, Piotr [Los Alamos National Laboratory (LANL)]·Noto, Vito [University of Padova, Italy]
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Abstract

The sluggish kinetics of the oxygen reduction reaction (ORR) hinder cost-effective polymer electrolyte fuel cells (PEFCs), which rely on scarce, expensive platinum-based electrocatalysts (ECs). Here, we present a novel synthesis method for ORR ECs achieving exceptional platinum utilization. The design features a hierarchical “multi-carbon” support comprising carbon nanoparticles interacting with graphene nanoplatelets as the “core”, encapsulated by a porous carbon nitride (CN) “shell”. This configuration promotes strong core/shell interactions and a bimodal active site distribution, consisting of chemically dispersed Pt and Ni single-atom complexes and PtNix alloy nanoclusters embedded in the CN shell. These advantages enable high activity and durability, achieving an ORR activity of 1.6 A mgPt−1 at 0.9 V vs. RHE-an order of magnitude higher than Pt/C (0.17 A mgPt−1). A proof-of-concept PEFC demonstrates a specific power of 12.0 kW gPt−1 at 0.60 V. This approach offers a significant step toward more efficient and sustainable PEFC technologies.

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Pagot, Gioele [University of Padova, Italy], Vezzu, Keti [University of Padova, Italy], Nale, Angeloclaudio [University of Padova, Italy], Bonaccorso, Francesco [Istituto Italiano di Technilogia], Kulesza, Pawel [Istituto Italiano di Tecnologia,], Rutkowska, Iwona [Istituto Italiano di Tecnologia,], Negro, Enrico [University of Padova, Italy], Zawodzinski, Thomas [University of Tennessee, Knoxville (UTK)], Cullen, David [ORNL] (ORCID:0000000225937866), Zelenay, Piotr [Los Alamos National Laboratory (LANL)], Noto, Vito [University of Padova, Italy]. 2026-05-01. Hierarchical low Pt-loading “core-shell” electrocatalysts for the oxygen reduction reaction in fuel cells. https://doi.org/10.1016/j.jpowsour.2026.239733

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