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Abstract Branched plasmonic nanocrystals (NCs) have attracted much attention due to electric field enhancements at their tips. Seeded growth provides routes to NCs with defined branching patterns and, in turn, near‐field distributions with defined symmetries. Here, a systematic analysis was undertaken in which seeds containing different distributions of planar defects were used to grow branched NCs in order to understand how their distributions direct the branching. Characterization of the products by multimode electron tomography and analysis of the NC morphologies at different overgrowth stages indicate that the branching patterns are directed by the seed defects, with the emergence of branches from the seed faces consistent with minimizing volumetric strain energy at the expense of surface energy. These results contrast with growth of branched NCs from single‐crystalline seeds and provide a new platform for the synthesis of symmetrically branched plasmonic NCs.
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Surface ligation stage revealed through polarity-dependent fluorescence during perovskite nanocrystal growth
Methylammonium lead iodide perovskite (MAPbI 3 ) nanocrystals (NCs) exhibit favorable photophysics for a range of light emitting applications. A comprehensive mechanistic understanding of the nucleation and growth processes for these NCs is still elusive. Absorbance and fluorescence spectra were measured during a NC synthesis with kinetics limited by precursor solvation using a rapid sampling technique wherein syringe filters quench NC growth. The signal from well-capped NCs in the reaction mixture was isolated by the use of polar syringe filters, enabling spectroscopic observation of the surface ligation process. Our results indicate that the formation of these NCs involves a single stage of nucleation and growth, followed by a terminal surface ligation stage.
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- Award ID(s):
- 1659346
- PAR ID:
- 10196304
- Date Published:
- Journal Name:
- Journal of Materials Chemistry C
- Volume:
- 8
- Issue:
- 21
- ISSN:
- 2050-7526
- Page Range / eLocation ID:
- 7041 to 7050
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/C9TC06545H
