Source:http://linkedlifedata.com/resource/pubmed/id/16004136
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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
4
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| pubmed:dateCreated |
2005-7-11
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| pubmed:abstractText |
Colloidal CdSe nanocrystals were synthesized in reaction media consisting of tri-n-octylphosphine (TOP) without addition of other species; the single-step approach used cadmium oxide (CdO) and TOPSe as Cd and Se sources, respectively. The temporal evolution of the optical properties of the growing TOP-capped CdSe nanocrystals was monitored for a couple of hours, showing that there are two distinguishable stages of growth: an early stage (less than 5 minutes) and a later stage; the growth kinetics of the two stages is a function of the Cd-to-Se precursor molar ratios. A rational choice of 2-6Cd-to-1Se molar ratio was found, based on the temporal evolution of the photoluminescent (PL) efficiency (studied as PL intensity and sensitivity to the media of dispersion, and non-resonant Stokes shifts). For a 2Cd-to-1Se synthesis, the growth in size was slow in the early stages and became fast in the later stages; this fast-later-stage feature could be suppressed by going to a synthesis with a 4-6Cd-to-1Se mole ratio: the nanocrystals between 0.5-60 min growth time exhibit very much similar optical properties, with less than 19 nm redshift of bandgap absorption and emission occurring. Thus, the synthetic route developed here, with a rational 4-6Cd-to-1Se molar ratio, enables us to produce high-quality CdSe nanocrystals on a large-scale with a high degree of synthetic reproducibility. The insights gained facilitate a deeper understanding of the concept of what constitutes high-quality nano-crystals: high PL efficiency resulting from a low growth rate, which can be thoroughly and readily investigated by the red-shift rate of the band-gap peak positions; in addition, the insights gained help us to define a proper synthetic approach for large-scale production with high-quality product.
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| pubmed:language |
eng
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| pubmed:journal | |
| pubmed:citationSubset |
IM
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| pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Cadmium,
http://linkedlifedata.com/resource/pubmed/chemical/Cadmium Compounds,
http://linkedlifedata.com/resource/pubmed/chemical/Colloids,
http://linkedlifedata.com/resource/pubmed/chemical/Furans,
http://linkedlifedata.com/resource/pubmed/chemical/Hexanes,
http://linkedlifedata.com/resource/pubmed/chemical/Ligands,
http://linkedlifedata.com/resource/pubmed/chemical/Organophosphorus Compounds,
http://linkedlifedata.com/resource/pubmed/chemical/Oxides,
http://linkedlifedata.com/resource/pubmed/chemical/Selenium,
http://linkedlifedata.com/resource/pubmed/chemical/Selenium Compounds,
http://linkedlifedata.com/resource/pubmed/chemical/Solvents,
http://linkedlifedata.com/resource/pubmed/chemical/cadmium oxide,
http://linkedlifedata.com/resource/pubmed/chemical/cadmium selenide,
http://linkedlifedata.com/resource/pubmed/chemical/tetrahydrofuran,
http://linkedlifedata.com/resource/pubmed/chemical/trioctyl phosphine oxide
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| pubmed:status |
MEDLINE
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| pubmed:month |
Apr
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| pubmed:issn |
1533-4880
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| pubmed:author | |
| pubmed:issnType |
Print
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| pubmed:volume |
5
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| pubmed:owner |
NLM
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| pubmed:authorsComplete |
Y
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| pubmed:pagination |
669-81
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| pubmed:dateRevised |
2006-11-15
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| pubmed:meshHeading |
pubmed-meshheading:16004136-Cadmium,
pubmed-meshheading:16004136-Cadmium Compounds,
pubmed-meshheading:16004136-Colloids,
pubmed-meshheading:16004136-Furans,
pubmed-meshheading:16004136-Hexanes,
pubmed-meshheading:16004136-Kinetics,
pubmed-meshheading:16004136-Ligands,
pubmed-meshheading:16004136-Microscopy, Electron, Transmission,
pubmed-meshheading:16004136-Nanotechnology,
pubmed-meshheading:16004136-Organophosphorus Compounds,
pubmed-meshheading:16004136-Oxides,
pubmed-meshheading:16004136-Selenium,
pubmed-meshheading:16004136-Selenium Compounds,
pubmed-meshheading:16004136-Semiconductors,
pubmed-meshheading:16004136-Solvents,
pubmed-meshheading:16004136-Temperature,
pubmed-meshheading:16004136-Thermodynamics,
pubmed-meshheading:16004136-Time Factors,
pubmed-meshheading:16004136-Ultraviolet Rays
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| pubmed:year |
2005
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| pubmed:articleTitle |
Colloidal CdSe nanocrystals from tri-n-octylphosphine: Part II: control of growth rate for high quality and large-scale production by tuning Cd-to-Se stoichiometry.
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| pubmed:affiliation |
Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario KIA OR6, Canada.
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| pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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