Results 201 to 210 of about 6,752 (248)

The synthesis and modification of CdTe/CdS core shell quantum dots

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2015
A simple and economical synthesis method of CdTe quantum dots (QDs) has been developed using glutathione as a modifier in an aqueous system. The fluorescent properties of as-prepared CdTe QDs at different reaction times were studied to optimize the synthesis conditions.
Jianqiu, Chen, An, Xiao, Zhengwei, Zhang, Yan, Yu, Zhengyu, Yan   +4 more
openaire   +2 more sources

Tailoring Colloidal Core–Shell Quantum Dots for Optoelectronics

2022
Colloidal core–shell quantum dots (QDs) are promising nanosystems exhibiting outstanding optical properties including enhanced photoluminescence quantum yield (PLQY), prolonged exciton lifetime, suppressed Auger recombination (AR) and improved photo-/chemical stability as compared to bare QDs.
Ali Imran Channa, Yimin You, Xin Tong, Zhiming M. Wang   +3 more
openaire   +1 more source

The Synthesis of Core/Shell Quantum Dots

2014
Quantum dots have desirable optical properties, yet often require further stabilisation to provide novel optical properties and to be practically useful. In this chapter we describe shelling chemistries and techniques, and the types of structures accessible, such as type I, type II and inverse shell heterostructures.
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Synthesis of type-II CdSe(S)/Fe2O3 core/shell quantum dots: the effect of shell on the properties of core/shell quantum dots

Journal of Materials Science, 2016
CdSe(S)/Fe2O3 core/shell quantum dots (QDs) were prepared in an aqueous synthetic route. These were shown to be highly crystalline nanoparticles using X-ray diffraction and HRTEM, whilst optical spectroscopy showed that the particles exhibited highly photoluminescent emissions. A red shift in the emission wavelength of CdSe(S) QDs coated with Fe2O3 was
Fatemeh Mirnajafizadeh, Fan Wang, Peter Reece, John Arron Stride   +3 more
openaire   +1 more source

Interdiffusion in core-shell and quantum-dot-quantum-well nanocrystals

The Journal of Chemical Physics, 2002
Theoretical calculations, utilizing the effective-mass theory, are presented of exciton energies in semiconductor core-shell and quantum-dot-quantum-well nanocrystals. For core-shell nanocrystals, the influence of diffusion on the transition energies is investigated.
openaire   +1 more source

Multiexcitons in a Single Core-Shell Colloidal Quantum dots

MRS Proceedings, 2009
AbstractThe micro-photoluminescence (μ-PL) spectra of a single CdTe/CdSe quasi- type II core-shell colloidal quantum dots (CQDs) unambiguously reveal an emission of a biexciton (2X), a triexciton (3X) and a quadraexciton (4X) under continuous-wave excitation. The CQDs were characterized by optical measurements and theoretical consideration of carrier's
Dima Cheskis, Ruth Osovsky, Viki Kloper, Aldona Sashchiuk, Efrat Lifshitz   +4 more
openaire   +1 more source

Core-Shell Structure and Photoluminescence of CdS Quantum Dots

Chinese Physics Letters, 2001
A double-potential-well model is proposed to describe the core-shell thickness-dependent photoluminescence peaks and energy relaxations in semiconductor quantum dots (QDs). The surface effect plays an important role in the formation of new states - polaronic states around the surface of QDs.
Zou Bing-Suo, Wu Zhen-Yu, Cao Li, Dai Jian-Hua, Zhang Ze-Bo, Nie Yu-Xin, Xie Si-Shen   +6 more
openaire   +1 more source

HAADF-STEM for the analysis of core–shell quantum dots

Journal of Materials Science, 2018
The capability of the imaging technique of high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) to detect the interface in small core/shell quantum dots (QDs) is investigated. In particular, two methodologies based on HAADF-STEM-simulated images are evaluated.
N. Fernández-Delgado, M. Herrera, J. Pizarro, P. Galindo, S. I. Molina   +4 more
openaire   +1 more source

Electronic and Optical Characteristics of Core/Shell Quantum Dots

2020
This chapter presents the results of a theoretical study of single-electron, two-electron, and impurity states as well as interband optical absorption and single-electron current in spherical and cylindrical core/shell quantum dots. Analytically exact solvable models of the confining potentials of core/shell quantum dots are discussed.
D. A. Baghdasaryan, H. T. Ghaltaghchyan, D. B. Hayrapetyan, E. M. Kazaryan, H. A. Sarkisyan   +4 more
openaire   +1 more source

Synthesis and characterization of CuInSe2 core–shell quantum dots

Glass Physics and Chemistry, 2016
A synthesis of 1-dodecanetiol stabilized colloidal quantum dots of CuInSe2 exhibiting photoluminescence in the range of 700–900 nm has been described. The effect of the shell on the energy levels of electrons in CuInSe2–ZnS and CuInSe2–ZnSe core–shell quantum dots has been investigated by quantum mechanical calculations.
D. S. Mazing, A. A. Karmanov, L. B. Matyushkin, O. A. Aleksandrova, I. A. Pronin, V. A. Moshnikov   +5 more
openaire   +1 more source