Overview
Français
ABSTRACT
Fluorescent semiconductor nanocrystals (quantum dots-QDs) exhibit very interesting optical properties : no photobleaching of their fluorescence over time (even under continuous excitation), narrow spectral width, easily tunable emission wavelength according to their size and chemical composition. However, their use remains limited : at a single particle level, their fluorescence fluctuates with time (blinking). A new type of quantum dots has been synthesized, with a strongly reduced blinking. This article presents the mechanisms of fluorescence and blinking of QDs, the general methods of synthesis, and the study of non-blinking nanocrystals with 100 % quantum yield at low temperature.
Read this article from a comprehensive knowledge base, updated and supplemented with articles reviewed by scientific committees.
Read the articleAUTHORS
-
Michel NASILOWSKI: PhD student, University of Paris VI, LPEM/ESPCI, 10, rue Vauquelin, 75005 Paris, France
-
Benoît DUBERTRET: Research Director, CNRS, LPEM/ESPCI, 10, rue Vauquelin, 75005 Paris, France
INTRODUCTION
Box 1 – History
The scientific community has been interested in semiconductor nanocrystals for some thirty years. Since their discovery in the early 1980s by Ekimov and Henglein , and their theoretical study by Efros and Brus , the synthesis protocols were improved and, in 1993, the first synthesis of size-controlled colloidal semiconductor nanocrystals was achieved. . Since this key synthesis, the field has undergone significant development, particularly since 2000, when new precursors that are less hazardous for synthesis were developed. . Since then, nanocrystals have been engineered: the band alignments of the various materials, the core/shell systems, etc., have all been designed and engineered. ... have made it possible to obtain materials with finely controllable physico-chemical properties, whose applications are now emerging on an industrial scale.
The Ultimate Scientific and Technical Reference
KEYWORDS
State of the art | single particle spectroscopy | synthesis of colloidal nanoparticles | luminophores in display devices | fluorescent markers for biomedical imaging | quantum dots | blinking | quantum yield
This article is included in
Technological innovations
This offer includes:
Knowledge Base
Updated and enriched with articles validated by our scientific committees
Services
A set of exclusive tools to complement the resources
Practical Path
Operational and didactic, to guarantee the acquisition of transversal skills
Doc & Quiz
Interactive articles with quizzes, for constructive reading
Non-flashing fluorescent nanocrystals: towards the perfect fluorophore
Properties of colloidal fluorescent semiconductor nanocrystals
Bibliography
Events
30 Years QDs – International conference celebrating 30 years of the discovery of colloidal QDs: May 26-28, 2014, ESPCI, Paris
( http://www.30-years-qds.com )
International Conference on Quantum Dots – International Conference on QDs, biannual
Directory
Laboratories – Design offices – Schools – Research centers (non-exhaustive list)
Laboratoire de physique et d'étude des matériaux (LPEM, UMR8213 CNRS/UPMC/ESPCI), 10, rue Vauquelin, 75005 Paris, France
Organic & Hybrid Molecular Electronics Laboratory...
The Ultimate Scientific and Technical Reference
