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This report highlights recent progress in the rational design, synthesis, and applications of bimetallic nanocrystals with integrated SERS and catalytic activities. The ultimate goal is to develop bifunctional nanocrystals as a SERS probe for monitoring a catalytic reaction in situ . We first introduce seeded growth as a facile and powerful route to the syntheses of bifunctional nanocrystals with catalytic activities arising from Au or Pd, in addition to plasmonic properties originating from Ag or Au. Specifically, we discuss two distinctive pathways, namely conformal and site-selected deposition of a second metal on the surface of a noble-metal nanocrystal seed, for the fabrication of bifunctional nanocrystals with controlled composition and morphology. We then discuss the application of these bifunctional nanocrystals as unique probes for in situ SERS monitoring of the Au or Pd-catalyzed reduction of 4-nitrothiophenol to 4-aminothiophenol by NaBH 4 and the Ag-catalyzed oxidation of 4-aminothiophenol to trans -4,4′-dimercaptoazobenzene by the O 2 from air. We conclude this review with perspectives on the future development.
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Bifunctional Metal Nanocrystals for Catalyzing and Reporting on Chemical Reactions
Abstract Bifunctional nanocrystals with integrated plasmonic and catalytic activities hold great promise for analyzing chemical reactions by in situ surface‐enhanced Raman spectroscopy. This Minireview gives a brief introduction to the general strategies for designing such nanocrystals, followed by four typical examples, including their fabrication, characterization, and potential limitation. We then use the reduction of 4‐nitrothiophenol and oxidation of 4‐aminothiophenol as two model systems to demonstrate the capabilities of these bifunctional nanocrystals to monitor chemical reactions for the elucidation of reaction mechanisms and measurement of kinetics. We conclude with perspectives on further development of these bifunctional nanocrystals into a viable platform for investigating other types of catalytic reactions.
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- Award ID(s):
- 1708300
- PAR ID:
- 10124665
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 59
- Issue:
- 10
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 3782-3792
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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