Giant PbSe/CdSe/CdSe Quantum Dots: Crystal-Structure-Defined Ultrastable Near-Infrared Photoluminescence from Single Nanocrystals
| Autor: | Andrei Piryatinski, Milan Sykora, Christina J. Hanson, Xuedan Ma, Yves J. Chabal, Han Htoon, Anton V. Malko, Jennifer A. Hollingsworth, Ajay Singh, John K. Grey, Joanna L. Casson, Nicolai F. Hartmann, William J. I. DeBenedetti |
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| Rok vydání: | 2017 |
| Předmět: |
Photoluminescence
business.industry Chemistry Ionic bonding Nanotechnology 02 engineering and technology General Chemistry Crystal structure 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Biochemistry Photobleaching Catalysis 0104 chemical sciences Colloid and Surface Chemistry Nanocrystal Quantum dot Optoelectronics Particle 0210 nano-technology business Wurtzite crystal structure |
| Zdroj: | Journal of the American Chemical Society. 139:11081-11088 |
| ISSN: | 1520-5126 0002-7863 |
| Popis: | Toward a truly photostable PbSe quantum dot (QD), we apply the thick-shell or "giant" QD structural motif to this notoriously environmentally sensitive nanocrystal system. Namely, using a sequential application of two shell-growth techniques-partial-cation exchange and successive ionic layer adsorption and reaction (SILAR)-we are able to overcoat the PbSe QDs with sufficiently thick CdSe shells to impart new single-QD-level photostability, as evidenced by suppression of both photobleaching and blinking behavior. We further reveal that the crystal structure of the CdSe shell (cubic zinc-blende or hexagonal wurtzite) plays a key role in determining the photoluminescence properties of these giant QDs, with only cubic nanocrystals sufficiently bright and stable to be observed as single emitters. Moreover, we demonstrate that crystal structure and particle shape (cubic, spherical, or tetrapodal) and, thereby, emission properties can be synthetically tuned by either withholding or including the coordinating ligand, trioctylphosphine, in the SILAR component of the shell-growth process. |
| Databáze: | OpenAIRE |
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