| Morphology control of cadmium selenide nanocrystals: insights into the roles of di-n-octylphosphine oxide (DOPO) and ucid (DOPA). | |
| | |
MedLine Citation:
|
PMID: 22369500 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
Di-n-octylphosphine oxide (DOPO) and di-n-octylphosphinic acid (DOPA), as two of impurities found in commercial tri-n-octylphosphine oxide (TOPO), generate significant differences in the outcomes of CdSe-nanocrystal (NC) syntheses. Using n-tetradecylphosphonic acid (TDPA) as the primary acid additive, quantum dots (QDs) are grown with DOPO added, whereas quantum rods (QRs) are grown in the presence of DOPA. While using oleic acid (OA) as the primary acid additive, QDs are generated and the QDs produced with DOPA exhibit larger sizes and size distributions than those produced with DOPO. (31)P NMR analyses of the reaction mixtures reveal that the majority of the DOPO has been converted into DOPA and di-n-octylphosphine (DOP) with DOP being removed via evacuation over the course of Cd-precursor preparation. The origin of the puzzling differences in the shape control of CdSe NCs in the presence of DOPO and DOPA is elucidated to be the small quantity of DOPO present, which liberates DOP during NC synthesis. In the presence of DOP, regardless of DOPA, the precursor-conversion kinetics and thus the nucleation kinetics are dramatically accelerated, generating a large number of nuclei by consuming a significant amount of CdSe nutrients, favoring QD growth. Similarly, QD growth is favored by the fast nucleation kinetics in the presence of OA, and the broader size distributions of QDs with DOPA are due to a second nucleation event initiated by the more stable Cd-di-n-octylphosphinate component. In contrast, a slow nucleation event results in the growth of QRs in the case of using DOPA and TDPA, where no DOPO or DOP is present. The results, thus, demonstrate the important role of precursor-conversion kinetics in the control of NC morphologies. |
| | |
Authors:
|
Fudong Wang; William E Buhro |
Publication Detail:
|
Type: Journal Article; Research Support, N.I.H., Extramural; Research Support, U.S. Gov't, Non-P.H.S. Date: 2012-03-06 |
Journal Detail:
|
Title: Journal of the American Chemical Society Volume: 134 ISSN: 1520-5126 ISO Abbreviation: J. Am. Chem. Soc. Publication Date: 2012 Mar |
Date Detail:
|
Created Date: 2012-03-21 Completed Date: 2012-07-25 Revised Date: 2013-03-25 |
Medline Journal Info:
|
Nlm Unique ID: 7503056 Medline TA: J Am Chem Soc Country: United States |
Other Details:
|
Languages: eng Pagination: 5369-80 Citation Subset: IM |
Affiliation:
|
Department of Chemistry and Center for Materials Innovation, Washington University, Saint Louis, Missouri 63130-4899, United States. fwang@wustl.edu |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Cadmium Compounds
/
chemical synthesis,
chemistry* Nanoparticles / chemistry* Organophosphorus Compounds / chemical synthesis, chemistry* Particle Size Selenium Compounds / chemical synthesis, chemistry* Surface Properties |
| Grant Support | |
ID/Acronym/Agency:
|
P41 RR000954-32/RR/NCRR NIH HHS; P41RR0954/RR/NCRR NIH HHS |
| Chemical | |
Reg. No./Substance:
|
0/Cadmium Compounds; 0/Organophosphorus Compounds; 0/Selenium Compounds; 0/di-n-octylphosphine oxide; 0/di-n-octylphosphinic acid; A7F646JC5C/cadmium selenide |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Duration of recognized fever in febrile seizure predicts later development of epilepsy.
Next Document: Marburg virus glycoprotein GP2: pH-dependent stability of the ectodomain ?-helical bundle.