Combining different precious metals to generate alloy nanocrystals with desirable shapes and compositions remains a challenge because of the low miscibility between these metals and/or the different reduction potentials of their salt precursors. Specifically, Rh and Pd are considered to be immiscible in the bulk solid over the entire composition range. Here we demonstrate that Rh−Pd alloy nanorods with well‐distributed and tunable compositions can be synthesized using a one‐pot polyol method. The success of our synthesis relies on the introduction of bromide as a coordination ligand to tune the redox potentials of Rh(III) and Pd(II) ions for the achievement of co‐reduction. The atomic ratio of the Rh−Pd alloy nanorods can be facilely tuned by changing the molar feeding ratio between the two precursors. We also systematically investigate the effects of water on the morphology of the Rh−Pd alloy nanocrystals. In an attempt to promote future use of these alloy nanorods, we successfully scale up their synthesis in a continuous‐flow reactor with no degradation to the product quality.
Decahedral nanocrystals have received great attention owing to their unique symmetry and strain‐energy distribution. In contrast to other noble metals, it has been difficult to synthesize decahedral Rh nanocrystals. We report a robust, one‐pot method based on polyol reduction for the facile synthesis of Rh decahedral nanocrystals in high purity, with sub‐20 nm sizes. The success of the synthesis relied on our ability to manipulate reduction kinetics by systematically tuning experimental parameters. We found that the yield of Rh decahedral nanocrystals could be maximized by optimizing:
- PAR ID:
- 10047659
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemNanoMat
- Volume:
- 4
- Issue:
- 1
- ISSN:
- 2199-692X
- Page Range / eLocation ID:
- p. 66-70
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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