Journal ArticleDOI
Epitaxial Growth of Highly Luminescent CdSe/CdS Core/Shell Nanocrystals with Photostability and Electronic Accessibility
TLDR
The synthesis of epitaxially grown, wurtzite CdSe/CdS core/shell nanocrystals is reported in this paper, where shells of up to three monolayers in thickness were grown on cores ranging in diameter from 23 to 39.Abstract:
The synthesis of epitaxially grown, wurtzite CdSe/CdS core/shell nanocrystals is reported Shells of up to three monolayers in thickness were grown on cores ranging in diameter from 23 to 39 A Shell growth was controllable to within a tenth of a monolayer and was consistently accompanied by a red shift of the absorption spectrum, an increase of the room temperature photoluminescence quantum yield (up to at least 50%), and an increase in the photostability Shell growth was shown to be uniform and epitaxial by the use of X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), and optical spectroscopy The experimental results indicate that in the excited state the hole is confined to the core and the electron is delocalized throughout the entire structure The photostability can be explained by the confinement of the hole, while the delocalization of the electron results in a degree of electronic accessibility that makes these nanocrystalsread more
Citations
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Journal ArticleDOI
Semiconductor Nanocrystals as Fluorescent Biological Labels
TL;DR: Semiconductor nanocrystals prepared for use as fluorescent probes in biological staining and diagnostics have a narrow, tunable, symmetric emission spectrum and are photochemically stable.
Journal ArticleDOI
Chemistry and properties of nanocrystals of different shapes.
TL;DR: The interest in nanoscale materials stems from the fact that new properties are acquired at this length scale and, equally important, that these properties are equally important.
Journal ArticleDOI
Quantum dot bioconjugates for imaging, labelling and sensing
TL;DR: This review looks at current methods for preparing QD bioconjugates as well as presenting an overview of applications, and concludes that the potential of QDs in biology has just begun to be realized and new avenues will arise as the ability to manipulate these materials improves.
Journal ArticleDOI
Experimental Determination of the Extinction Coefficient of CdTe, CdSe, and CdS Nanocrystals
TL;DR: In this article, the extinction coefficient per mole of nanocrystals at the first exitonic absorption peak, e.g., for high-quality CdTe, CdSe, and CdS, was found to be strongly dependent on the size of the nanocrystal, between a square and a cubic dependence.
Journal ArticleDOI
Shape control of CdSe nanocrystals
Xiaogang Peng,Liberato Manna,Liberato Manna,Liberato Manna,Weidong Yang,Weidong Yang,Weidong Yang,Juanita N. Wickham,Juanita N. Wickham,Juanita N. Wickham,Erik C. Scher,Erik C. Scher,Erik C. Scher,Andreas Kadavanich,Andreas Kadavanich,Andreas Kadavanich,A. P. Alivisatos,A. P. Alivisatos,A. P. Alivisatos +18 more
TL;DR: Control of the growth kinetics of the II–VI semiconductor cadmium selenide can be used to vary the shapes of the resulting particles from a nearly spherical morphology to a rod-like one, with aspect ratios as large as ten to one.
References
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Journal ArticleDOI
Semiconductor Clusters, Nanocrystals, and Quantum Dots
TL;DR: In this article, the authors focus on the properties of quantum dots and their ability to join the dots into complex assemblies creates many opportunities for scientific discovery, such as the ability of joining the dots to complex assemblies.
Journal ArticleDOI
Synthesis and characterization of nearly monodisperse CdE (E = sulfur, selenium, tellurium) semiconductor nanocrystallites
TL;DR: In this paper, a simple route to the production of high-quality CdE (E=S, Se, Te) semiconductor nanocrystallites is presented, based on pyrolysis of organometallic reagents by injection into a hot coordinating solvent.
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Perspectives on the Physical Chemistry of Semiconductor Nanocrystals
TL;DR: In this paper, the present status and new opportunities for research in this area of materials physical chemistry are reviewed, as well as a review of the present state and opportunities in this field.
Journal ArticleDOI
Synthesis and Characterization of Strongly Luminescing ZnS-Capped CdSe Nanocrystals
TL;DR: In this paper, the authors describe the synthesis of ZnS-capped CdSe semiconductor nanocrystals using organometallic reagents by a two-step single-flask method X-ray photoelectron spectroscopy, transmission electron microscopy and optical absorption.
Journal ArticleDOI
Nanometer-sized semiconductor clusters: materials synthesis, quantum size effects, and photophysical properties
Ying Wang,Norman Herron +1 more
TL;DR: In this article, the size effect on the optical and photophysical properties of semiconductor clusters has been studied in the condensed phase and the current status of materials synthesis and the prospect for making monodisperse clusters of well-defined surfaces has been discussed.