Journal ArticleDOI
(CdSe)ZnS Core-Shell Quantum Dots - Synthesis and Characterization of a Size Series of Highly Luminescent Nanocrystallites
B. O. Dabbousi,Javier Rodríguez-Viejo,F. V. Mikulec,Jason Heine,Hedi Mattoussi,R. Ober,K. F. Jensen,‡,§ and,Moungi G. Bawendi +7 more
Reads0
Chats0
TLDR
In this paper, a synthesis of highly luminescent (CdSe)ZnS composite quantum dots with CdSe cores ranging in diameter from 23 to 55 A was reported.Abstract:
We report a synthesis of highly luminescent (CdSe)ZnS composite quantum dots with CdSe cores ranging in diameter from 23 to 55 A. The narrow photoluminescence (fwhm ≤ 40 nm) from these composite dots spans most of the visible spectrum from blue through red with quantum yields of 30−50% at room temperature. We characterize these materials using a range of optical and structural techniques. Optical absorption and photoluminescence spectroscopies probe the effect of ZnS passivation on the electronic structure of the dots. We use a combination of wavelength dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, small and wide angle X-ray scattering, and transmission electron microscopy to analyze the composite dots and determine their chemical composition, average size, size distribution, shape, and internal structure. Using a simple effective mass theory, we model the energy shift for the first excited state for (CdSe)ZnS and (CdSe)CdS dots with varying shell thickness. Finally, we characterize the...read more
Citations
More filters
Journal ArticleDOI
Toxicity of nanocrystal quantum dots: the relevance of surface modifications.
TL;DR: Accumulating evidence suggests that the QD-capping material, rather than the core metalloid complex, is responsible for the majority of their toxicity and biological activity.
Patent
Nanofiber surface based capacitors
TL;DR: In this article, the authors provide novel capacitors comprising nanofiber enhanced surface area substrates and structures comprising such capacitors, as well as methods and uses for capacitors.
Journal ArticleDOI
Evolution of the Single-Nanocrystal Photoluminescence Linewidth with Size and Shell: Implications for Exciton–Phonon Coupling and the Optimization of Spectral Linewidths
Jian Cui,Andrew P. Beyler,Igor Coropceanu,Liam Cleary,Thomas R. Avila,Yue Chen,Jose M. Cordero,S. Leigh Heathcote,Daniel K. Harris,Ou Chen,Jianshu Cao,Moungi G. Bawendi +11 more
TL;DR: It is found that the single-nanocrystal linewidth at room temperature is heavily influenced by the nature of the CdSe surface and the epitaxial shell, which have a profound impact on the internal electric fields that affect exciton-phonon coupling.
Journal ArticleDOI
PbTe|CdTe Core|Shell Particles by Cation Exchange, a HR-TEM study
TL;DR: In this article, high-resolution transmission electron microscopy was used to assess the formation of PbTe, CdTe and PbSe|CdSe core|shell nanoparticles by cationic exchange.
Journal ArticleDOI
Synthesis and characterization of core-shell GaP@GaN and GaN@GaP nanowires
Hung Min Lin,Yong Lin Chen,Jian Yang,Yao Chung Liu,Kai Min Yin,Ji-Jung Kai,Fu-Rong Chen,Li-Chyong Chen,Yang-Fang Chen,Chia Chun Chen +9 more
TL;DR: In this article, a thermal CVD route to core−shell GaP@GaN and GaN@GaP nanowires was developed, and structural analyses indicate that the nanows exhibit a two-layer and wire-like structure.
References
More filters
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.