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Abstract Facet‐selective etching and deposition, as determined by the landscape of surface energy, represent two powerful methods for the transformation of noble‐metal nanocrystals into nanostructures with complex shapes or morphologies. This review highlights the use of these two methods, including integration of them, for the fabrication of novel monometallic and bimetallic nanostructures with enhanced properties. We start with an introduction to the role of surface capping in controlling the facet‐selective etching or deposition on the surface of Ag nanocrystals, followed by a case study of how to maneuver etching and deposition at different facets of Pd nanocrystals for the fabrication of nanoframes. We then introduce the use of galvanic replacement to accomplish selective etching and deposition on two different facets in an orthogonal manner, transforming Pd nanocubes into Pd−Pt octapods. By complementing galvanic replacement with a chemical reduction reaction, it is also feasible to control the rates of these two reactions for the conversion of Ag nanocubes into Ag@Ag−Au concave nanocubes and Ag@Au core‐shell nanocubes. These transformation methods not only greatly increase the shape diversity of metal nanocrystals but also offer nanocrystals with enhanced plasmonic and/or catalytic properties.
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This content will become publicly available on November 13, 2026
Trimetallic Pd@PtxAu1−x Core-Shell Nanocubes with Enhanced Selectivity toward H2O2 for the Oxygen Reduction Reaction
We report a versatile method based on seed-mediated growth for the facile synthesis of trimetallic Pd@PtxAu1−x core-shell nanocubes. By simply varying the feeding ratio between the Pt(II) and Au(III) precursors, the atomic ratio of Pt to Au in the shell and thereby the ensemble state of Pt atoms on the surface can be tuned to control the binding configuration of O2 molecules. Specifically, discrete Pt atoms on the surface promote the adsorption of O2 molecules in the Pauling configuration to enhance the catalytic selectivity of the nanoparticles toward H2O2 via the two-electron oxygen reduction reaction, with the Pd@Pt0.025Au0.975 nanocubes showing selectivity as high as 91% at 0.45 VRHE. This work offers a viable means to augment the electrocatalytic performance of alloy nanocrystals by controlling their surface compositions.
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- Award ID(s):
- 2333595
- PAR ID:
- 10651699
- Publisher / Repository:
- Scilight Press
- Date Published:
- Journal Name:
- Materials and Interfaces
- Volume:
- 2
- Issue:
- 4
- ISSN:
- 2982-2394
- Page Range / eLocation ID:
- 397 to 405
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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