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Abstract The development of dual catalysts with high efficiency toward oxygen reduction and evolution reactions (ORR and OER) in acidic media is a significant challenge. Here an active and durable dual catalyst based upon cubic Pt39Ir10Pd11nanocages with an average edge length of 12.3 nm, porous walls as thin as 1.0 nm, and well‐defined {100} facets is reported. The trimetallic nanocages perform better than all the reported dual catalysts in acidic media, with a low ORR‐OER overpotential gap of only 704 mV at a Pt‐Ir‐Pd loading of 16.8 µgPt+Ir+Pdcm−2geo. For ORR at 0.9 V, when benchmarked against the commercial Pt/C and Pt‐Pd nanocages, the trimetallic nanocages exhibit an enhanced mass activity of 0.52 A mg−1Pt+Ir+Pd(about four and two times as high as those of the Pt/C and Pt‐Pd nanocages) and much improved durability. For OER, the trimetallic nanocages show a remarkable mass activity of 0.20 A mg−1Pt+Irat 1.53 V, which is 16.7 and 4.3 fold relative to those of the Pt/C and Pt‐Pd nanocages, respectively. These improvements can be ascribed to the highly open structure of the nanocages, and the possible electronic coupling between Ir and Pt atoms in the lattice.
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Compressively Strained and Interconnected Platinum Cones with Greatly Enhanced Activity and Durability toward Oxygen Reduction
Abstract The synthesis of cone‐shaped Pt nanoparticles featuring compressively‐strained {111} facets by depositing Pt atoms on the vertices of Pd icosahedral nanocrystals, followed by selective removal of the Pd template via wet etching, is reported. By controlling the lateral dimensions down to ca. 3 nm, together with a thickness of ca. 2 nm, the Pt cones show greatly enhanced specific and mass activities toward oxygen reduction, with values being 2.8 and 6.4 times those of commercial Pt/C, respectively. Both the strain field and the observed activity trend are rationalized using density functional theory calculations. With the formation of ultrathin linkers among the Pt cones derived from the same Pd icosahedral seed, the interconnected Pt cones acquire stronger interactions with the carbon support, preventing them from detachment and aggregation during the catalytic reaction. Even after 20 000 cycles of accelerated durability test, the Pt cones still show a mass activity 5.3 times higher than the initial value of the Pt/C.
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- Award ID(s):
- 2105602
- PAR ID:
- 10593856
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 34
- Issue:
- 45
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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