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Synthesis and characterization of CdS(x)Se(1−x) alloy quantum dots with composition-dependent band gaps and paramagnetic properties

Ternary CdS(x)Se(1−x) alloy quantum dots (QDs) and CdS(x)Se(1−x)/ZnS core/shell nanocrystals exhibiting composition dependent band gaps have been successfully synthesized. The ZnS shell was doped with 0.1% and 5% of paramagnetic manganese ions so as to be used as a fluorescent/paramagnetic bi-functi...

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Autores principales: Chung, Yueh-Chi, Yang, Chien-Hsin, Zheng, Hao-Wen, Tsai, Ping-Szu, Wang, Tzong-Liu
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The Royal Society of Chemistry 2018
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9085248/
https://www.ncbi.nlm.nih.gov/pubmed/35547268
http://dx.doi.org/10.1039/c8ra06007j
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author Chung, Yueh-Chi
Yang, Chien-Hsin
Zheng, Hao-Wen
Tsai, Ping-Szu
Wang, Tzong-Liu
author_facet Chung, Yueh-Chi
Yang, Chien-Hsin
Zheng, Hao-Wen
Tsai, Ping-Szu
Wang, Tzong-Liu
author_sort Chung, Yueh-Chi
collection PubMed
description Ternary CdS(x)Se(1−x) alloy quantum dots (QDs) and CdS(x)Se(1−x)/ZnS core/shell nanocrystals exhibiting composition dependent band gaps have been successfully synthesized. The ZnS shell was doped with 0.1% and 5% of paramagnetic manganese ions so as to be used as a fluorescent/paramagnetic bi-functional probe. Energy-dispersive X-ray spectroscopy (EDS) measurements confirmed the presence of Cd, S, and Se in CdS(x)Se(1−x) nanocrystals with the atomic ratios of Cd, S, and Se which are well consistent with our synthetic ratios. Wide angle X-ray diffraction (WAXD) indicated that the crystal structures of the CdS(x)Se(1−x) core QDs and CdS(x)Se(1−x)/ZnS core/shell QDs were zinc blende phases. Both dynamic light scattering (DLS) and transmission electron microscopy (TEM) revealed that the as-synthesized nanocrystals had a narrow size distribution and high crystallinity. The band gaps of CdS(x)Se(1−x) nanocrystals were adjustable by varying the ratio of S:Se in the CdS(x)Se(1−x) core and were in the range of 1.96 eV to 2.32 eV. Hence, when composition x was changed from 0 to 1, the fluorescence color of the nanocrystals varied from red to green. After shell coverage, the ternary alloy QDs exhibited a superior photoluminescence (PL) quantum yield up to 57%. In comparison with the alloy core QDs, the PL emission peaks of the CdS(x)Se(1−x)/ZnS core/shell QDs displayed a small redshift. Electron paramagnetic resonance (EPR) measurements for manganese-doped CdS(x)Se(1−x)/ZnS nanocrystals revealed paramagnetic properties for both low and high Mn(2+) doping levels.
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spelling pubmed-90852482022-05-10 Synthesis and characterization of CdS(x)Se(1−x) alloy quantum dots with composition-dependent band gaps and paramagnetic properties Chung, Yueh-Chi Yang, Chien-Hsin Zheng, Hao-Wen Tsai, Ping-Szu Wang, Tzong-Liu RSC Adv Chemistry Ternary CdS(x)Se(1−x) alloy quantum dots (QDs) and CdS(x)Se(1−x)/ZnS core/shell nanocrystals exhibiting composition dependent band gaps have been successfully synthesized. The ZnS shell was doped with 0.1% and 5% of paramagnetic manganese ions so as to be used as a fluorescent/paramagnetic bi-functional probe. Energy-dispersive X-ray spectroscopy (EDS) measurements confirmed the presence of Cd, S, and Se in CdS(x)Se(1−x) nanocrystals with the atomic ratios of Cd, S, and Se which are well consistent with our synthetic ratios. Wide angle X-ray diffraction (WAXD) indicated that the crystal structures of the CdS(x)Se(1−x) core QDs and CdS(x)Se(1−x)/ZnS core/shell QDs were zinc blende phases. Both dynamic light scattering (DLS) and transmission electron microscopy (TEM) revealed that the as-synthesized nanocrystals had a narrow size distribution and high crystallinity. The band gaps of CdS(x)Se(1−x) nanocrystals were adjustable by varying the ratio of S:Se in the CdS(x)Se(1−x) core and were in the range of 1.96 eV to 2.32 eV. Hence, when composition x was changed from 0 to 1, the fluorescence color of the nanocrystals varied from red to green. After shell coverage, the ternary alloy QDs exhibited a superior photoluminescence (PL) quantum yield up to 57%. In comparison with the alloy core QDs, the PL emission peaks of the CdS(x)Se(1−x)/ZnS core/shell QDs displayed a small redshift. Electron paramagnetic resonance (EPR) measurements for manganese-doped CdS(x)Se(1−x)/ZnS nanocrystals revealed paramagnetic properties for both low and high Mn(2+) doping levels. The Royal Society of Chemistry 2018-08-24 /pmc/articles/PMC9085248/ /pubmed/35547268 http://dx.doi.org/10.1039/c8ra06007j Text en This journal is © The Royal Society of Chemistry https://creativecommons.org/licenses/by-nc/3.0/
spellingShingle Chemistry
Chung, Yueh-Chi
Yang, Chien-Hsin
Zheng, Hao-Wen
Tsai, Ping-Szu
Wang, Tzong-Liu
Synthesis and characterization of CdS(x)Se(1−x) alloy quantum dots with composition-dependent band gaps and paramagnetic properties
title Synthesis and characterization of CdS(x)Se(1−x) alloy quantum dots with composition-dependent band gaps and paramagnetic properties
title_full Synthesis and characterization of CdS(x)Se(1−x) alloy quantum dots with composition-dependent band gaps and paramagnetic properties
title_fullStr Synthesis and characterization of CdS(x)Se(1−x) alloy quantum dots with composition-dependent band gaps and paramagnetic properties
title_full_unstemmed Synthesis and characterization of CdS(x)Se(1−x) alloy quantum dots with composition-dependent band gaps and paramagnetic properties
title_short Synthesis and characterization of CdS(x)Se(1−x) alloy quantum dots with composition-dependent band gaps and paramagnetic properties
title_sort synthesis and characterization of cds(x)se(1−x) alloy quantum dots with composition-dependent band gaps and paramagnetic properties
topic Chemistry
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9085248/
https://www.ncbi.nlm.nih.gov/pubmed/35547268
http://dx.doi.org/10.1039/c8ra06007j
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