A Library of Selenourea Precursors to PbSe Nanocrystals with Size Distributions near the Homogeneous Limit.

Autor: Campos MP; Department of Chemistry, Columbia University , New York, New York 10027, United States., Hendricks MP; Department of Chemistry, Columbia University , New York, New York 10027, United States., Beecher AN; Department of Chemistry, Columbia University , New York, New York 10027, United States., Walravens W; Department of Chemistry, Columbia University , New York, New York 10027, United States.; Physics and Chemistry of Nanostructures Group (PCN), Ghent University , B-9000 Ghent, Belgium., Swain RA; Department of Chemistry, Columbia University , New York, New York 10027, United States., Cleveland GT; Department of Chemistry, Columbia University , New York, New York 10027, United States., Hens Z; Physics and Chemistry of Nanostructures Group (PCN), Ghent University , B-9000 Ghent, Belgium.; Center of Nano and Biophotonics, Ghent University , B-9000 Ghent, Belgium., Sfeir MY; Center for Functional Nanomaterials, Brookhaven National Laboratory , Upton, New York 11973, United States., Owen JS; Department of Chemistry, Columbia University , New York, New York 10027, United States.
Jazyk: angličtina
Zdroj: Journal of the American Chemical Society [J Am Chem Soc] 2017 Feb 15; Vol. 139 (6), pp. 2296-2305. Date of Electronic Publication: 2017 Feb 06.
DOI: 10.1021/jacs.6b11021
Abstrakt: We report a tunable library of N,N,N'-trisubstituted selenourea precursors and their reaction with lead oleate at 60-150 °C to form carboxylate-terminated PbSe nanocrystals in quantitative yields. Single exponential conversion kinetics can be tailored over 4 orders of magnitude by adjusting the selenourea structure. The wide range of conversion reactivity allows the extent of nucleation ([nanocrystal] = 4.6-56.7 μM) and the size following complete precursor conversion (d = 1.7-6.6 nm) to be controlled. Narrow size distributions (σ = 0.5-2%) are obtained whose spectral line widths are dominated (73-83%) by the intrinsic single particle spectral broadening, as observed using spectral hole burning measurements. The intrinsic broadening decreases with increasing size (fwhm = 320-65 meV, d = 1.6-4.4 nm) that derives from exciton fine structure and exciton-phonon coupling rather than broadening caused by the size distribution.
Databáze: MEDLINE