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Abstract Fabrication of 3dmetal‐based core@shell nanocatalysts with engineered Pt‐surfaces provides an effective approach for improving the catalytic performance. The challenges in such preparation include shape control of the 3dmetallic cores and thickness control of the Pt‐based shells. Herein, we report a colloidal seed‐mediated method to prepare octahedral CuNi@Pt‐Cu core@shell nanocrystals using CuNi octahedral cores as the template. By precisely controlling the synthesis conditions including the deposition rate and diffusion rate of the shell‐formation through tuning the capping ligand, reaction temperature, and heating rate, uniform Pt‐based shells can be achieved with a thickness of <1 nm. The resultant carbon‐supported CuNi@Pt‐Cu core@shell nano‐octahedra showed superior activity in electrochemical methanol oxidation reaction (MOR) compared with the commercial Pt/C catalysts and carbon‐supported CuNi@Pt‐Cu nano‐polyhedron counterparts.
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MoOy-Pt(CuNi)x heterojunction nanostructured catalyst for promoting the oxygen reduction reaction activity property
The catalyst intrinsic area-specific activity for the oxygen reduction reaction (ORR) was constrained by the scaling relations governing the adsorption of reaction intermediates. In this study, we strategically modified the electronic band structures of Pt(CuNi)x alloy nanoparticles by varying their composition, resulting in a specific activity trend resembling a volcano shape. The introduction of MoOy shattered the existing scaling relations, leading to a significant enhancement in ORR activity of Pt alloys, surpassing the activity of Pt(CuNi)x catalysts. These findings proved the effectiveness of MoOy deposition on Pt(CuNi)x in disrupting the scaling relations, ultimately improving ORR activity.
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- Award ID(s):
- 1955452
- PAR ID:
- 10504460
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Catalysis Communications
- Volume:
- 186
- Issue:
- C
- ISSN:
- 1566-7367
- Page Range / eLocation ID:
- 106835
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.catcom.2023.106835
