Two-Step Nucleation and Growth of InP Quantum Dots via Magic-Sized Cluster Intermediates
Journal Article
·
· Chemistry of Materials
- Univ. of Washington, Seattle, WA (United States). Dept. of Chemistry
- Columbia Univ., New York, NY (United States). Dept. of Applied Physics and Applied Mathematics
- Columbia Univ., New York, NY (United States). Dept. of Applied Physics and Applied Mathematics; Brookhaven National Lab. (BNL), Upton, NY (United States). Condensed Matter Physics and Materials Science Dept.
We report on the role of magic-sized clusters (MSCs) as key intermediates in the synthesis of indium phosphide quantum dots (InP QDs) from molecular precursors. These observations suggest that previous efforts to control nucleation and growth by tuning precursor reactivity have been undermined by formation of these kinetically persistent MSCs prior to QD formation. The thermal stability of InP MSCs is influenced by the presence of exogenous bases as well as choice of the anionic ligand set. Addition of a primary amine, a common additive in previous InP QD syntheses, to carboxylate terminated MSCs was found to bypass the formation of MSCs, allowing for homogeneous growth of InP QDs through a continuum of isolable sizes. Substitution of the carboxylate ligand set for a phosphonate ligand set increased the thermal stability of one particular InP MSC to 400°C. The structure and optical properties of the MSCs with both carboxylate and phosphonate ligand sets were studied by UV-Vis absorption spectroscopy, powder XRD analysis, and solution ³¹P{¹H} and ¹H NMR spectroscopy. Finally, the carboxylate terminated MSCs were identified as effective single source precursors (SSPs) for the synthesis of high quality InP QDs. Employing InP MSCs as SSPs for QDs effectively decouples the formation of MSCs from the subsequent second nucleation event and growth of InP QDs. The concentration dependence of this SSP reaction, as well as the shape uniformity of particles observed by TEM suggests that the stepwise growth from MSCs directly to QDs proceeds via a second nucleation event rather than an aggregative growth mechanism.
- Research Organization:
- Brookhaven National Laboratory (BNL)
- Sponsoring Organization:
- USDOE SC OFFICE OF BASIC ENERGY SCIENCES
- OSTI ID:
- 1182518
- Alternate ID(s):
- OSTI ID: 1229493
- Report Number(s):
- BNL--107509-2015-JA; KC0202010
- Journal Information:
- Chemistry of Materials, Journal Name: Chemistry of Materials Journal Issue: 4 Vol. 27; ISSN 0897-4756
- Publisher:
- American Chemical Society (ACS)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Indium–Poly(carboxylic acid) Ligand Interactions Modify InP Quantum Dot Nucleation and Growth
Synthesis and characterization of InP and InN colloidal quantum dots.
Synthesis and characterization of InP, GaP, and GaInP{sub 2} quantum dots
Journal Article
·
Tue Jul 25 20:00:00 EDT 2023
· Chemistry of Materials
·
OSTI ID:1993125
Synthesis and characterization of InP and InN colloidal quantum dots.
Conference
·
Thu Mar 31 23:00:00 EST 2005
·
OSTI ID:966933
Synthesis and characterization of InP, GaP, and GaInP{sub 2} quantum dots
Journal Article
·
Thu May 11 00:00:00 EDT 1995
· Journal of Physical Chemistry
·
OSTI ID:50791