Materials Science › Materials Chemistry

Quantum Dots Synthesis And Properties

Works Count: 69873

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This cluster of papers explores the diverse applications of quantum dots and nanocrystals in various fields such as bioimaging, photovoltaics, fluorescence imaging, biological detection, and nanoparticle synthesis. The research covers topics ranging from quantum dot solar cells to in vivo molecular and cellular imaging using quantum dots.

Keywords

Quantum Dots; Nanocrystals; Bioimaging; Photovoltaics; Semiconductor Nanocrystals; Fluorescence Imaging; Colloidal Nanocrystals; Biological Detection; Solar Cells; Nanoparticle Synthesis

Shape control of CdSe nanocrystals

2000-03-01

Xiaogang Peng , Liberato Manna , Weidong Yang +4 more

Renal clearance of quantum dots

2007-09-23

Hak Soo Choi , Wenhao Liu , Preeti Misra +5 more

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Immunofluorescent labeling of cancer marker Her2 and other cellular targets with semiconductor quantum dots

2002-12-02

Xingyong Wu , Hongjian Liu , Jian‐Quan Liu +6 more

Chemistry and Properties of Nanocrystals of Different Shapes

2005-03-18

Clemens Burda , Xiaobo Chen , Radha Narayanan +1 more

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTChemistry and Properties of Nanocrystals of Different ShapesClemens Burda, Xiaobo Chen, Radha Narayanan, and Mostafa A. El-SayedView Author Information Center for Chemical Dynamics and Nanomaterials Research, Department … ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTChemistry and Properties of Nanocrystals of Different ShapesClemens Burda, Xiaobo Chen, Radha Narayanan, and Mostafa A. El-SayedView Author Information Center for Chemical Dynamics and Nanomaterials Research, Department of Chemistry, Case Western Reserve UniversityMillis 2258, Cleveland, Ohio 44106, and Laser Dynamics Laboratory, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400 Cite this: Chem. Rev. 2005, 105, 4, 1025–1102Publication Date (Web):March 18, 2005Publication History Received22 July 2004Published online18 March 2005Published inissue 1 April 2005https://pubs.acs.org/doi/10.1021/cr030063ahttps://doi.org/10.1021/cr030063aresearch-articleACS PublicationsCopyright © 2005 American Chemical SocietyRequest reuse permissionsArticle Views71691Altmetric-Citations6546LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose SUBJECTS:Absorption,Electrical energy,Metal nanoparticles,Nanocrystals,Nanoparticles Get e-Alerts

Optical Gain and Stimulated Emission in Nanocrystal Quantum Dots

2000-10-13

Victor I. Klimov , Alexander Mikhailovsky , Su Xu +5 more

The development of optical gain in chemically synthesized semiconductor nanoparticles (nanocrystal quantum dots) has been intensely studied as the first step toward nanocrystal quantum dot lasers. We examined the competing … The development of optical gain in chemically synthesized semiconductor nanoparticles (nanocrystal quantum dots) has been intensely studied as the first step toward nanocrystal quantum dot lasers. We examined the competing dynamical processes involved in optical amplification and lasing in nanocrystal quantum dots and found that, despite a highly efficient intrinsic nonradiative Auger recombination, large optical gain can be developed at the wavelength of the emitting transition for close-packed solids of these dots. Narrowband stimulated emission with a pronounced gain threshold at wavelengths tunable with the size of the nanocrystal was observed, as expected from quantum confinement effects. These results unambiguously demonstrate the feasibility of nanocrystal quantum dot lasers.

In Vivo Imaging of Quantum Dots Encapsulated in Phospholipid Micelles

2002-11-29

Benoît Dubertret , Paris A. Skourides , David J. Norris +3 more

Fluorescent semiconductor nanocrystals (quantum dots) have the potential to revolutionize biological imaging, but their use has been limited by difficulties in obtaining nanocrystals that are biocompatible. To address this problem, … Fluorescent semiconductor nanocrystals (quantum dots) have the potential to revolutionize biological imaging, but their use has been limited by difficulties in obtaining nanocrystals that are biocompatible. To address this problem, we encapsulated individual nanocrystals in phospholipid block–copolymer micelles and demonstrated both in vitro and in vivo imaging. When conjugated to DNA, the nanocrystal-micelles acted as in vitro fluorescent probes to hybridize to specific complementary sequences. Moreover, when injected into Xenopus embryos, the nanocrystal-micelles were stable, nontoxic (<5 × 10 9 nanocrystals per cell), cell autonomous, and slow to photobleach. Nanocrystal fluorescence could be followed to the tadpole stage, allowing lineage-tracing experiments in embryogenesis.

Second window for in vivo imaging

2009-11-01

Andrew M. Smith , Michael C. Mancini , Shuming Nie

Mechanisms of Nucleation and Growth of Nanoparticles in Solution

2014-07-08

Nguyễn Thị Kim Thanh , N. Maclean , S. Mahiddine

ADVERTISEMENT RETURN TO ISSUEPREVReviewNEXTMechanisms of Nucleation and Growth of Nanoparticles in SolutionNguyen T. K. Thanh*, N. Maclean, and S. MahiddineView Author Information Department of Physics and Astronomy, University College London, … ADVERTISEMENT RETURN TO ISSUEPREVReviewNEXTMechanisms of Nucleation and Growth of Nanoparticles in SolutionNguyen T. K. Thanh*, N. Maclean, and S. MahiddineView Author Information Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT, United Kingdom UCL Healthcare Biomagnetic and Nanomaterials Laboratories, 21 Albemarle Street, London, W1S 4BS, United Kingdom*E-mail: [email protected]Cite this: Chem. Rev. 2014, 114, 15, 7610–7630Publication Date (Web):July 8, 2014Publication History Received14 October 2013Published online8 July 2014Published inissue 13 August 2014https://pubs.acs.org/doi/10.1021/cr400544shttps://doi.org/10.1021/cr400544sreview-articleACS PublicationsCopyright © 2014 American Chemical Society. This publication is licensed under CC-BY. This publication is Open Access under the license indicated. Learn MoreArticle Views244126Altmetric-Citations2193LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail PDF (14 MB) Get e-AlertscloseSUBJECTS:Gold,Metal nanoparticles,Nanoparticles,Nucleation,Silver Get e-Alerts

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Kinetics of II-VI and III-V Colloidal Semiconductor Nanocrystal Growth: “Focusing” of Size Distributions

1998-05-14

Xiaogang Peng , Jacob D. Wickham , A. Paul Alivisatos

ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTKinetics of II-VI and III-V Colloidal Semiconductor Nanocrystal Growth: "Focusing" of Size DistributionsXiaogang Peng, J. Wickham, and A. P. AlivisatosView Author Information Department of Chemistry, University of … ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTKinetics of II-VI and III-V Colloidal Semiconductor Nanocrystal Growth: "Focusing" of Size DistributionsXiaogang Peng, J. Wickham, and A. P. AlivisatosView Author Information Department of Chemistry, University of California Berkeley and Materials Sciences Division Lawrence Berkeley National Lab Berkeley, California 94720-1460 Cite this: J. Am. Chem. Soc. 1998, 120, 21, 5343–5344Publication Date (Web):May 14, 1998Publication History Received18 February 1998Published online14 May 1998Published inissue 1 June 1998https://pubs.acs.org/doi/10.1021/ja9805425https://doi.org/10.1021/ja9805425rapid-communicationACS PublicationsCopyright © 1998 American Chemical SocietyRequest reuse permissionsArticle Views22646Altmetric-Citations1691LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (1)»Supporting Information Supporting Information SUBJECTS:Cadmium selenide,Crystallization,Monomers,Nanocrystals,Nanoparticles Get e-Alerts

Long-term multiple color imaging of live cells using quantum dot bioconjugates

2002-12-02

Jyoti K. Jaiswal , Hedi Mattoussi , J. Matthew Mauro +1 more

Water-Soluble Quantum Dots for Multiphoton Fluorescence Imaging in Vivo

2003-05-29

Daniel R. Larson , Warren R. Zipfel , Rebecca M. Williams +4 more

The use of semiconductor nanocrystals (quantum dots) as fluorescent labels for multiphoton microscopy enables multicolor imaging in demanding biological environments such as living tissue. We characterized water-soluble cadmium selenide-zinc sulfide … The use of semiconductor nanocrystals (quantum dots) as fluorescent labels for multiphoton microscopy enables multicolor imaging in demanding biological environments such as living tissue. We characterized water-soluble cadmium selenide-zinc sulfide quantum dots for multiphoton imaging in live animals. These fluorescent probes have two-photon action cross sections as high as 47,000 Goeppert-Mayer units, by far the largest of any label used in multiphoton microscopy. We visualized quantum dots dynamically through the skin of living mice, in capillaries hundreds of micrometers deep. We found no evidence of blinking (fluorescence intermittency) in solution on nanosecond to millisecond time scales.

Fluorescence intermittency in single cadmium selenide nanocrystals

1996-10-01

M. Nirmal , B. O. Dabbousi , Moungi G. Bawendi +4 more

Optical properties of manganese-doped nanocrystals of ZnS

1994-01-17

R. N. Bhargava , Dolores Gallagher‐Thompson , X. Hong +1 more

We report for the first time that doped nanocrystals of semiconductor can yield both high luminescent efficiencies and lifetime shortening at the same time. Nanocrystals of Mn-doped ZnS with sizes … We report for the first time that doped nanocrystals of semiconductor can yield both high luminescent efficiencies and lifetime shortening at the same time. Nanocrystals of Mn-doped ZnS with sizes varying from 3.5 to 7.5 nm were prepared by a room temperature chemical process. These nanosized particles have an external photoluminescent quantum efficiency as high as 18% at room temperature and a luminescent decay at least 5 orders of magnitude faster than the corresponding ${\mathrm{Mn}}^{2+}$ radiative transition in the bulk crystals. Luminescent measurements show that the efficiency increases with decreasing size of the particles, as expected within the framework of an electron-hole localization theory. These results suggest that doped nanocrystals are indeed a new class of materials heretofore unknown.

Synthesis and characterization of nearly monodisperse CdE (E = sulfur, selenium, tellurium) semiconductor nanocrystallites

1993-09-01

C. B. Murray , David J. Norris , Moungi G. Bawendi

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis and characterization of nearly monodisperse CdE (E = sulfur, selenium, tellurium) semiconductor nanocrystallitesC. B. Murray, D. J. Norris, and M. G. BawendiCite this: J. Am. Chem. … ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis and characterization of nearly monodisperse CdE (E = sulfur, selenium, tellurium) semiconductor nanocrystallitesC. B. Murray, D. J. Norris, and M. G. BawendiCite this: J. Am. Chem. Soc. 1993, 115, 19, 8706–8715Publication Date (Print):September 1, 1993Publication History Published online1 May 2002Published inissue 1 September 1993https://pubs.acs.org/doi/10.1021/ja00072a025https://doi.org/10.1021/ja00072a025research-articleACS PublicationsRequest reuse permissionsArticle Views65449Altmetric-Citations7838LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

Near-infrared fluorescent type II quantum dots for sentinel lymph node mapping

2003-12-07

Sungjee Kim , Yong Taik Lim , Edward G. Soltesz +7 more

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Electroluminescence from single monolayers of nanocrystals in molecular organic devices

2002-12-01

Seth Coe , Wing-Keung Woo , Moungi G. Bawendi +1 more

Self-Organization of CdSe Nanocrystallites into Three-Dimensional Quantum Dot Superlattices

1995-11-24

C. B. Murray , Cherie R. Kagan , Moungi G. Bawendi

The self-organization of CdSe nanocrystallites into three-dimensional semiconductor quantum dot superlattices (colloidal crystals) is demonstrated. The size and spacing of the dots within the superlattice are controlled with near atomic … The self-organization of CdSe nanocrystallites into three-dimensional semiconductor quantum dot superlattices (colloidal crystals) is demonstrated. The size and spacing of the dots within the superlattice are controlled with near atomic precision. This control is a result of synthetic advances that provide CdSe nanocrystallites that are monodisperse within the limit of atomic roughness. The methodology is not limited to semiconductor quantum dots but provides general procedures for the preparation and characterization of ordered structures of nanocrystallites from a variety of materials.

Synthesis and Characterization of Strongly Luminescing ZnS-Capped CdSe Nanocrystals

1996-01-01

Margaret A. Hines , Philippe Guyot‐Sionnest

We 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 are consistent with nanocrystals … We 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 are consistent with nanocrystals containing a core of nearly monodisperse CdSe of 27−30 Å diameter with a ZnS capping 6 ± 3 Å thick. The ZnS capping with a higher bandgap than CdSe passivates the core crystallite removing the surface traps. The nanocrystals exhibit strong and stable band-edge luminescence with a 50% quantum yield at room temperature.

Epitaxial Growth of Highly Luminescent CdSe/CdS Core/Shell Nanocrystals with Photostability and Electronic Accessibility

1997-07-01

Xiaogang Peng , M. C. Schlamp , A. V. Kadavanich +1 more

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 … 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 Å. 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 nanocrystals attractive for use in optoelectronic devices.

(CdSe)ZnS Core−Shell Quantum Dots: Synthesis and Characterization of a Size Series of Highly Luminescent Nanocrystallites

1997-11-01

B. O. Dabbousi , J. Rodríguez‐Viejo , Frederic V. Mikulec +5 more

We report a synthesis of highly luminescent (CdSe)ZnS composite quantum dots with CdSe cores ranging in diameter from 23 to 55 Å. The narrow photoluminescence (fwhm ≤ 40 nm) from … We report a synthesis of highly luminescent (CdSe)ZnS composite quantum dots with CdSe cores ranging in diameter from 23 to 55 Å. 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 growth of ZnS on CdSe cores as locally epitaxial and determine how the structure of the ZnS shell influences the photoluminescence properties.

Quantum Dot Solar Cells. Semiconductor Nanocrystals as Light Harvesters

2008-10-18

Prashant V. Kamat

The emergence of semiconductor nanocrystals as the building blocks of nanotechnology has opened up new ways to utilize them in next generation solar cells. This paper focuses on the recent … The emergence of semiconductor nanocrystals as the building blocks of nanotechnology has opened up new ways to utilize them in next generation solar cells. This paper focuses on the recent developments in the utilization of semiconductor quantum dots for light energy conversion. Three major ways to utilize semiconductor dots in solar cell include (i) metal−semiconductor or Schottky junction photovoltaic cell (ii) polymer−semiconductor hybrid solar cell, and (iii) quantum dot sensitized solar cell. Modulation of band energies through size control offers new ways to control photoresponse and photoconversion efficiency of the solar cell. Various strategies to maximize photoinduced charge separation and electron transfer processes for improving the overall efficiency of light energy conversion are discussed. Capture and transport of charge carriers within the semiconductor nanocrystal network to achieve efficient charge separation at the electrode surface remains a major challenge. Directing the future research efforts toward utilization of tailored nanostructures will be an important challenge for the development of next generation solar cells.

Semiconductor Nanocrystals as Fluorescent Biological Labels

1998-09-25

Marcel P. Bruchez , Mario M. Moronne , Peter Gin +2 more

Semiconductor nanocrystals were prepared for use as fluorescent probes in biological staining and diagnostics. Compared with conventional fluorophores, the nanocrystals have a narrow, tunable, symmetric emission spectrum and are photochemically … Semiconductor nanocrystals were prepared for use as fluorescent probes in biological staining and diagnostics. Compared with conventional fluorophores, the nanocrystals have a narrow, tunable, symmetric emission spectrum and are photochemically stable. The advantages of the broad, continuous excitation spectrum were demonstrated in a dual-emission, single-excitation labeling experiment on mouse fibroblasts. These nanocrystal probes are thus complementary and in some cases may be superior to existing fluorophores.

Probing the Cytotoxicity of Semiconductor Quantum Dots

2003-12-10

Austin M. Derfus , Warren C. W. Chan , Sangeeta N. Bhatia

With their bright, photostable fluorescence, semiconductor quantum dots (QDs) show promise as alternatives to organic dyes for biological labeling. Questions about their potential cytotoxicity, however, remain unanswered. While cytotoxicity of … With their bright, photostable fluorescence, semiconductor quantum dots (QDs) show promise as alternatives to organic dyes for biological labeling. Questions about their potential cytotoxicity, however, remain unanswered. While cytotoxicity of bulk cadmium selenide (CdSe) is well documented, a number of groups have suggested that CdSe QDs are cytocompatible, at least with some immortalized cell lines. Using primary hepatocytes as a liver model, we found that CdSe-core QDs were indeed acutely toxic under certain conditions. Specifically, we found that the cytotoxicity of QDs was modulated by processing parameters during synthesis, exposure to ultraviolet light, and surface coatings. Our data further suggest that cytotoxicity correlates with the liberation of free Cd2+ ions due to deterioration of the CdSe lattice. When appropriately coated, CdSe-core QDs can be rendered nontoxic and used to track cell migration and reorganization in vitro. Our results provide information for design criteria for the use of QDs in vitro and especially in vivo, where deterioration over time may occur.

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Formation of High-Quality CdTe, CdSe, and CdS Nanocrystals Using CdO as Precursor

2000-12-09

Zhe Peng , Xiaogang Peng

ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTFormation of High-Quality CdTe, CdSe, and CdS Nanocrystals Using CdO as PrecursorZ. Adam Peng and Xiaogang PengView Author Information Department of Chemistry and Biochemistry University of Arkansas, … ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTFormation of High-Quality CdTe, CdSe, and CdS Nanocrystals Using CdO as PrecursorZ. Adam Peng and Xiaogang PengView Author Information Department of Chemistry and Biochemistry University of Arkansas, Fayetteville, Arkansas 72701 Cite this: J. Am. Chem. Soc. 2001, 123, 1, 183–184Publication Date (Web):December 9, 2000Publication History Received10 October 2000Published online9 December 2000Published inissue 1 January 2001https://pubs.acs.org/doi/10.1021/ja003633mhttps://doi.org/10.1021/ja003633mrapid-communicationACS PublicationsCopyright © 2001 American Chemical SocietyRequest reuse permissionsArticle Views37905Altmetric-Citations2433LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose SUBJECTS:Cadmium,Cadmium selenide,Crystallization,Nanocrystals,Nucleation Get e-Alerts

Experimental Determination of the Extinction Coefficient of CdTe, CdSe, and CdS Nanocrystals

2003-06-07

William W. Yu , Lianhua Qu , Wenzhuo Guo +1 more

The extinction coefficient per mole of nanocrystals at the first exitonic absorption peak, ε, for high-quality CdTe, CdSe, and CdS nanocrystals was found to be strongly dependent on the size … The extinction coefficient per mole of nanocrystals at the first exitonic absorption peak, ε, for high-quality CdTe, CdSe, and CdS nanocrystals was found to be strongly dependent on the size of the nanocrystals, between a square and a cubic dependence. The measurements were carried out using either nanocrystals purified with monitored purification procedures or nanocrystals prepared through controlled etching methods. The nature of the surface ligands, the refractive index of the solvents, the PL quantum yield of the nanocrystals, the methods used for the synthesis of the nanocrystals, and the temperature for the measurements all did not show detectable influence on the extinction coefficient for a given sized nanocrystal within experimental error.

A general strategy for nanocrystal synthesis

2005-08-31

Xun Wang , Jing Zhuang , Qing Peng +1 more

Hybrid Nanorod-Polymer Solar Cells

2002-03-29

Wendy U. Huynh , Janke J. Dittmer , A. Paul Alivisatos

We demonstrate that semiconductor nanorods can be used to fabricate readily processed and efficient hybrid solar cells together with polymers. By controlling nanorod length, we can change the distance on … We demonstrate that semiconductor nanorods can be used to fabricate readily processed and efficient hybrid solar cells together with polymers. By controlling nanorod length, we can change the distance on which electrons are transported directly through the thin film device. Tuning the band gap by altering the nanorod radius enabled us to optimize the overlap between the absorption spectrum of the cell and the solar emission spectrum. A photovoltaic device consisting of 7-nanometer by 60-nanometer CdSe nanorods and the conjugated polymer poly-3(hexylthiophene) was assembled from solution with an external quantum efficiency of over 54% and a monochromatic power conversion efficiency of 6.9% under 0.1 milliwatt per square centimeter illumination at 515 nanometers. Under Air Mass (A.M.) 1.5 Global solar conditions, we obtained a power conversion efficiency of 1.7%.

Transmission Electron Microscopy of Shape-Controlled Nanocrystals and Their Assemblies

2000-01-11

Zhong Lin Wang

The physical and chemical properties of nanophase materials rely on their crystal and surface structures. Transmission electron microscopy (TEM) is a powerful and unique technique for structure characterization. The most … The physical and chemical properties of nanophase materials rely on their crystal and surface structures. Transmission electron microscopy (TEM) is a powerful and unique technique for structure characterization. The most important application of TEM is the atomic-resolution real-space imaging of nanoparticles. This article introduces the fundamentals of TEM and its applications in structural determination of shape-controlled nanocrystals and their assemblies. By forming a nanometer size electron probe, TEM is unique in identifying and quantifying the chemical and electronic structure of individual nanocrystals. Electron energy-loss spectroscopy analysis of the solid-state effects and mapping the valence states are even more attractive. In situ TEM is demonstrated for characterizing and measuring the thermodynamic, electric, and mechanical properties of individual nanostructures, from which the structure−property relationship can be registered with a specific nanoparticle/structure.

Nanometer-sized semiconductor clusters: materials synthesis, quantum size effects, and photophysical properties

1991-01-01

Ying Wang , N. Herron

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTNanometer-sized semiconductor clusters: materials synthesis, quantum size effects, and photophysical propertiesYing Wang and N. HerronCite this: J. Phys. Chem. 1991, 95, 2, 525–532Publication Date (Print):January 1, 1991Publication … ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTNanometer-sized semiconductor clusters: materials synthesis, quantum size effects, and photophysical propertiesYing Wang and N. HerronCite this: J. Phys. Chem. 1991, 95, 2, 525–532Publication Date (Print):January 1, 1991Publication History Published online1 May 2002Published inissue 1 January 1991https://pubs.acs.org/doi/10.1021/j100155a009https://doi.org/10.1021/j100155a009research-articleACS PublicationsRequest reuse permissionsArticle Views7600Altmetric-Citations1757LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access options Get e-Alerts

Prospects of Colloidal Nanocrystals for Electronic and Optoelectronic Applications

2009-12-03

Dmitri V. Talapin , Jong‐Soo Lee , Maksym V. Kovalenko +1 more

ADVERTISEMENT RETURN TO ISSUEPREVReviewNEXTProspects of Colloidal Nanocrystals for Electronic and Optoelectronic ApplicationsDmitri V. Talapin*†‡, Jong-Soo Lee†, Maksym V. Kovalenko†, and Elena V. Shevchenko‡View Author Information Department of Chemistry, The University … ADVERTISEMENT RETURN TO ISSUEPREVReviewNEXTProspects of Colloidal Nanocrystals for Electronic and Optoelectronic ApplicationsDmitri V. Talapin*†‡, Jong-Soo Lee†, Maksym V. Kovalenko†, and Elena V. Shevchenko‡View Author Information Department of Chemistry, The University of Chicago, Chicago, Illinois 60637, and Center for Nanoscale Materials, Argonne National Lab, Argonne, Illinois 60439* To whom correspondence should be addressed. E-mail: [email protected]†The University of Chicago.‡Argonne National Lab.Cite this: Chem. Rev. 2010, 110, 1, 389–458Publication Date (Web):December 3, 2009Publication History Received5 April 2009Published online3 December 2009Published inissue 13 January 2010https://doi.org/10.1021/cr900137kCopyright © 2009 American Chemical SocietyRIGHTS & PERMISSIONSACS AuthorChoiceArticle Views67616Altmetric-Citations3374LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (16 MB) Get e-AlertsSUBJECTS:Cadmium selenide,Layers,Ligands,Nanoparticles,Semiconductors Get e-Alerts

Quantum dots versus organic dyes as fluorescent labels

2008-08-28

Ute Resch‐Genger , Markus Grabolle , Sara Cavalière +2 more

Structural diversity in binary nanoparticle superlattices

2006-01-01

Elena V. Shevchenko , Dmitri V. Talapin , Nicholas A. Kotov +2 more

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Core/Shell Semiconductor Nanocrystals

2009-01-19

Peter Reiß , Myriam Protière , Liang Li

Abstract Colloidal core/shell nanocrystals contain at least two semiconductor materials in an onionlike structure. The possibility to tune the basic optical properties of the core nanocrystals, for example, their fluorescence … Abstract Colloidal core/shell nanocrystals contain at least two semiconductor materials in an onionlike structure. The possibility to tune the basic optical properties of the core nanocrystals, for example, their fluorescence wavelength, quantum yield, and lifetime, by growing an epitaxial‐type shell of another semiconductor has fueled significant progress on the chemical synthesis of these systems. In such core/shell nanocrystals, the shell provides a physical barrier between the optically active core and the surrounding medium, thus making the nanocrystals less sensitive to environmental changes, surface chemistry, and photo‐oxidation. The shell further provides an efficient passivation of the surface trap states, giving rise to a strongly enhanced fluorescence quantum yield. This effect is a fundamental prerequisite for the use of nanocrystals in applications such as biological labeling and light‐emitting devices, which rely on their emission properties. Focusing on recent advances, this Review discusses the fundamental properties and synthesis methods of core/shell and core/multiple shell structures of II–VI, IV–VI, and III–V semiconductors. magnified image

Electronic wave functions in semiconductor clusters: experiment and theory

1986-06-01

Louis E. Brus

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTElectronic wave functions in semiconductor clusters: experiment and theoryLouis BrusCite this: J. Phys. Chem. 1986, 90, 12, 2555–2560Publication Date (Print):June 1, 1986Publication History Published online1 May 2002Published … ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTElectronic wave functions in semiconductor clusters: experiment and theoryLouis BrusCite this: J. Phys. Chem. 1986, 90, 12, 2555–2560Publication Date (Print):June 1, 1986Publication History Published online1 May 2002Published inissue 1 June 1986https://pubs.acs.org/doi/10.1021/j100403a003https://doi.org/10.1021/j100403a003research-articleACS PublicationsRequest reuse permissionsArticle Views19082Altmetric-Citations2773LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access options Get e-Alerts

Emergence of colloidal quantum-dot light-emitting technologies

2012-12-27

Yasuhiro Shirasaki , Geoffrey Supran , Moungi G. Bawendi +1 more

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Colloidal nanocrystal synthesis and the organic–inorganic interface

2004-09-28

Yadong Yin , A. Paul Alivisatos

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Quantum Dot Bioconjugates for Ultrasensitive Nonisotopic Detection

1998-09-25

Warren C. W. Chan , Shuming Nie

Highly luminescent semiconductor quantum dots (zinc sulfide–capped cadmium selenide) have been covalently coupled to biomolecules for use in ultrasensitive biological detection. In comparison with organic dyes such as rhodamine, this … Highly luminescent semiconductor quantum dots (zinc sulfide–capped cadmium selenide) have been covalently coupled to biomolecules for use in ultrasensitive biological detection. In comparison with organic dyes such as rhodamine, this class of luminescent labels is 20 times as bright, 100 times as stable against photobleaching, and one-third as wide in spectral linewidth. These nanometer-sized conjugates are water-soluble and biocompatible. Quantum dots that were labeled with the protein transferrin underwent receptor-mediated endocytosis in cultured HeLa cells, and those dots that were labeled with immunomolecules recognized specific antibodies or antigens.

Applications of nanoparticles in biology and medicine

2004-04-30

OV Salata

Nanomaterials are at the leading edge of the rapidly developing field of nanotechnology. Their unique size-dependent properties make these materials superior and indispensable in many areas of human activity. This … Nanomaterials are at the leading edge of the rapidly developing field of nanotechnology. Their unique size-dependent properties make these materials superior and indispensable in many areas of human activity. This brief review tries to summarise the most recent developments in the field of applied nanomaterials, in particular their application in biology and medicine, and discusses their commercialisation prospects.

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In vivo cancer targeting and imaging with semiconductor quantum dots

2004-07-18

Xiaohu Gao , Yuanyuan Cui , Richard M. Levenson +2 more

Ultra-large-scale syntheses of monodisperse nanocrystals

2004-11-28

Jongnam Park , Kwangjin An , Yosun Hwang +6 more

Semiconductor Clusters, Nanocrystals, and Quantum Dots

1996-02-16

A. Paul Alivisatos

Current research into semiconductor clusters is focused on the properties of quantum dots—fragments of semiconductor consisting of hundreds to many thousands of atoms—with the bulk bonding geometry and with surface … Current research into semiconductor clusters is focused on the properties of quantum dots—fragments of semiconductor consisting of hundreds to many thousands of atoms—with the bulk bonding geometry and with surface states eliminated by enclosure in a material that has a larger band gap. Quantum dots exhibit strongly size-dependent optical and electrical properties. The ability to join the dots into complex assemblies creates many opportunities for scientific discovery.

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Synthesis and Characterization of Monodisperse Nanocrystals and Close-Packed Nanocrystal Assemblies

2000-08-01

C. B. Murray , Cherie R. Kagan , Moungi G. Bawendi

▪ Abstract Solution phase syntheses and size-selective separation methods to prepare semiconductor and metal nanocrystals, tunable in size from ∼1 to 20 nm and monodisperse to ≤5%, are presented. Preparation … ▪ Abstract Solution phase syntheses and size-selective separation methods to prepare semiconductor and metal nanocrystals, tunable in size from ∼1 to 20 nm and monodisperse to ≤5%, are presented. Preparation of monodisperse samples enables systematic characterization of the structural, electronic, and optical properties of materials as they evolve from molecular to bulk in the nanometer size range. Sample uniformity makes it possible to manipulate nanocrystals into close-packed, glassy, and ordered nanocrystal assemblies (superlattices, colloidal crystals, supercrystals). Rigorous structural characterization is critical to understanding the electronic and optical properties of both nanocrystals and their assemblies. At inter-particle separations 5–100 Å, dipole-dipole interactions lead to energy transfer between neighboring nanocrystals, and electronic tunneling between proximal nanocrystals gives rise to dark and photoconductivity. At separations <5 Å, exchange interactions cause otherwise insulating assemblies to become semiconducting, metallic, or superconducting depending on nanocrystal composition. Tailoring the size and composition of the nanocrystals and the length and electronic structure of the matrix may tune the properties of nanocrystal solid-state materials.

Quantum dot solar cells

2002-04-01

Arthur J. Nozik

Solution-processed PbS quantum dot infrared photodetectors and photovoltaics

2005-01-09

S. A. McDonald , Gerasimos Konstantatos , Shiguo Zhang +4 more

Quantum dot bioconjugates for imaging, labelling and sensing

2005-06-01

Igor L. Medintz , H. Tetsuo Uyeda , Ellen R. Goldman +1 more

Quantum Dots for Live Cells, in Vivo Imaging, and Diagnostics

2005-01-27

Xavier Michalet , Fabien Pinaud , Laurent A. Bentolila +7 more

Research on fluorescent semiconductor nanocrystals (also known as quantum dots or qdots) has evolved over the past two decades from electronic materials science to biological applications. We review current approaches … Research on fluorescent semiconductor nanocrystals (also known as quantum dots or qdots) has evolved over the past two decades from electronic materials science to biological applications. We review current approaches to the synthesis, solubilization, and functionalization of qdots and their applications to cell and animal biology. Recent examples of their experimental use include the observation of diffusion of individual glycine receptors in living neurons and the identification of lymph nodes in live animals by near-infrared emission during surgery. The new generations of qdots have far-reaching potential for the study of intracellular processes at the single-molecule level, high-resolution cellular imaging, long-term in vivo observation of cell trafficking, tumor targeting, and diagnostics.

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Light-emitting diodes made from cadmium selenide nanocrystals and a semiconducting polymer

1994-08-01

Vicki L. Colvin , M. C. Schlamp , A. Paul Alivisatos

Luminescent quantum dots for multiplexed biological detection and imaging

2002-02-01

Warren C. W. Chan , Dustin J. Maxwell , Xiaohu Gao +3 more

Perspectives on the Physical Chemistry of Semiconductor Nanocrystals

1996-01-01

A. Paul Alivisatos

Semiconductor nanocrystals exhibit a wide range of size-dependent properties. Variations in fundamental characteristics ranging from phase transitions to electrical conductivity can be induced by controlling the size of the crystals. … Semiconductor nanocrystals exhibit a wide range of size-dependent properties. Variations in fundamental characteristics ranging from phase transitions to electrical conductivity can be induced by controlling the size of the crystals. The present status and new opportunities for research in this area of materials physical chemistry are reviewed.

Synthesis of Monodisperse Spherical Nanocrystals

2007-05-25

Jongnam Park , Jin Joo , Soon Gu Kwon +2 more

Much progress has been made over the past ten years on the synthesis of monodisperse spherical nanocrystals. Mechanistic studies have shown that monodisperse nanocrystals are produced when the burst of … Much progress has been made over the past ten years on the synthesis of monodisperse spherical nanocrystals. Mechanistic studies have shown that monodisperse nanocrystals are produced when the burst of nucleation that enables separation of the nucleation and growth processes is combined with the subsequent diffusion-controlled growth process through which the crystal size is determined. Several chemical methods have been used to synthesize uniform nanocrystals of metals, metal oxides, and metal chalcogenides. Monodisperse nanocrystals of CdSe, Co, and other materials have been generated in surfactant solution by nucleation induced at high temperature, and subsequent aging and size selection. Monodisperse nanocrystals of many metals and metal oxides, including magnetic ferrites, have been synthesized directly by thermal decomposition of metal-surfactant complexes prepared from the metal precursors and surfactants. Nonhydrolytic sol-gel reactions have been used to synthesize various transition-metal-oxide nanocrystals. Monodisperse gold nanocrystals have been obtained from polydisperse samples by digestive-ripening processes. Uniform-sized nanocrystals of gold, silver, platinum, and palladium have been synthesized by polyol processes in which metal salts are reduced by alcohols in the presence of appropriate surfactants.

Artificial atoms by design

2025-06-25

| Nature Synthesis

Ultrahigh‐Resolution Full‐Color Quantum Dot LEDs Based on Region‐Selective Interfacial Self‐Assembly

2025-06-25

Chao Zhong , Kuibao Yu , Yuan Qie +6 more | Advanced Functional Materials

Abstract Colloidal quantum dots (QDs) have shown great promise in the development of high‐resolution displays for near‐eye visual communication with the outside world. However, achieving full‐color high‐precision assembly of QDs … Abstract Colloidal quantum dots (QDs) have shown great promise in the development of high‐resolution displays for near‐eye visual communication with the outside world. However, achieving full‐color high‐precision assembly of QDs at the nanoscale remains a critical challenge. This study proposes a novel strategy for the region‐selective assembly of QDs for achieving ultra‐high‐resolution light‐emitting devices. This approach leverages interface‐assembled ultrathin surface microstructures to create specific wettability patterns, guiding the selective assembly of QDs on their surfaces. Ultimately, an ultra‐high‐resolution 36 599 pixels per inch (PPI) light‐emitting device is successfully realized, with a record‐high external quantum efficiency (EQE) of 18.74%. The addition of a molecular microstructure enhances the fidelity of the assembled QDs pattern, providing nearly a two‐fold increase in contrast ratio while effectively suppressing device leakage current. Additionally, the assembly process is compatible with photo‐crosslinking technology, resulting in a full‐color light‐emitting device with an EQE of 11.01%. Our strategy paves a simple and effective way for advancements in high‐performance nano‐display technology.

A XMS-CASPT2 study on the photophysics of a thio-caged single-atom fluorescence switch

2025-06-24

Yu-Xin Heng , Ya‐Qiong Guo , G. S. Li +4 more | Computational and Theoretical Chemistry

Diminishing Surface Defects in Silver Indium Sulfide Quantum Dots Enables Bandgap‐Excitonic Characteristics

2025-06-24

Julian Georg Mann , Ekaterina Kostyurina , Markus Döblinger +3 more | Advanced Optical Materials

Abstract I‐III‐VI quantum dots are eco‐friendly alternatives for next‐generation light‐emitting and harvesting devices. The study investigates the optical properties of Ag‐In‐S‐based quantum dots, focusing on excitonic transitions and sub‐bandgap defects. … Abstract I‐III‐VI quantum dots are eco‐friendly alternatives for next‐generation light‐emitting and harvesting devices. The study investigates the optical properties of Ag‐In‐S‐based quantum dots, focusing on excitonic transitions and sub‐bandgap defects. Uniquely synthesized AgInS 2 quantum dots emit via free excitons but dominate with broad, red‐shifted emission from energy‐distributed donor–acceptor pair defects. Photoluminescence excitation spectroscopy unveils charge carrier relaxation pathways with varying efficiencies within the defect states. Gallium sulfide coating forms a core/shell structure, passivating defects and transforming the inhomogeneous sub‐bandgap energy landscape into a more homogeneous one. A narrow free exciton emission and sharp absorption onset with two exciton signatures, X1 and X2, become prominent. Theoretical calculations reveal the band structure, showing that these transitions result from the excitation between two distinct valence band maxima and the conduction band minimum. Femtosecond transient transmission spectroscopy shows a defect trapping time of 590 fs in core quantum dots, while exciton filling prevails in core/shell, with formation times of 560 fs (X1) and 320 fs (X2). This study provides new insights into the optical properties of Ag‐In‐S‐based quantum dots by demonstrating how the computed band structure explains the experimentally observed excitonic features, with ultrafast spectroscopy capturing the exciton formation and trap‐state filling dynamics.

Calamitic ligand design for quantum dot assembly

2025-06-24

Samia Islam Liba , Alauna C. Wheeler , Jocelyn Ochoa +5 more | Journal of Applied Physics

We report the design and use of calamitic ligands for quantum dot surface modification and nanoparticle assembly. Ligands incorporating a rigid aromatic rod-like core have previously been shown to facilitate … We report the design and use of calamitic ligands for quantum dot surface modification and nanoparticle assembly. Ligands incorporating a rigid aromatic rod-like core have previously been shown to facilitate the formation of porous nanoparticle-based structures, such as solid-walled capsules and multi-compartment quantum dot foams and networks via liquid crystal phase transition templating—a process in which the host phase is quenched through the isotropic-nematic phase transition. The effect of the calamitic ligand structure on particle dispersion, transport, and subsequent assembly, however, requires further investigation, particularly in the case of anisotropic liquid crystal solvents. In this report, we vary the structure of six new calamitic ligands and characterize quantum dot size and packing into superstructures when modified with each ligand. Dynamic light scattering is used to measure the effective nanoparticle size for each ligand in dilute toluene solution. Transmission electron microscopy reveals nanoparticle distribution in dense drop-cast films for each ligand, and small-angle x-ray scattering is used to measure interparticle separations in the assembled porous structures. Together, these methods provide a full picture of particle packing for each ligand. Notably, our findings demonstrate that while longer, more rigid aromatic cores promote a closer packing structure in drop-cast films (a slow quasi-equilibrium process)—such effects are not evident using a rapid quenching method. This study highlights the fact that when nanoparticles are formed into macroscopic assemblies, both ligand design and the particular method of assembly can contribute significantly to the final packing structure.

Spontaneous Electric Field Directionality in One-Dimensional Semiconductors: Key to Efficient Charge Migration, Minimizing Recombination, and Enhancing Photocatalytic Performance

2025-06-24

Zhi Yang , Guangxiang Lu , Pengfei Jiang +2 more | Chemistry of Materials

A review of site-controlled compound semiconductor quantum dots for single photon emitters

2025-06-23

Yaonan Hou | Materials for Quantum Technology

Abstract Single photon emitters (SPEs) serve as the fundamental building blocks of photonic networks for applications in quantum information science and technology. This review paper focuses specifically on the rapidly … Abstract Single photon emitters (SPEs) serve as the fundamental building blocks of photonic networks for applications in quantum information science and technology. This review paper focuses specifically on the rapidly growing area of site-controlled and deterministically fabricated compound semiconductor quantum dots (QDs), which holds great potential for scalability given their high quantum efficiency, flexible coherence tunability and compatibility with silicon photonics. In this paper, the state-of-the-art growth and fabrication approaches, integration with photonic structures have been reviewed. Meanwhile, the emission properties from QD-based SPEs, including brightness, purity and coherence tunability, have been discussed. This review also provides an outlook of future developments of site-controlled QDs, offering insights into the progress toward scalable quantum photonic systems.

Metamorphosis from Quantum Dots to Quantum Shells and Highly Efficient Quantum Shell Light–Emitting Diodes

2025-06-23

Zhao Chen , Xiaohan Chen , Xiao Yuan +2 more | Advanced Science

The bottom-up design of chemical structure affords 0D nanocrystals (NCs) with tunable band structures and unexpected optical properties. Herein, an example of alloyed quantum shell (QS) is demonstrated by tailoring … The bottom-up design of chemical structure affords 0D nanocrystals (NCs) with tunable band structures and unexpected optical properties. Herein, an example of alloyed quantum shell (QS) is demonstrated by tailoring the chemical compositions in its core/shell structure. In the CdZnSe/ZnSeS/CdSeS/CdS (C/S1/S2/S3, in which C is the CdZnSe core and S represents the shells) structure, there is an intriguing metamorphosis from quantum dot (QD) to QS (that is, C and C/S1 belong to QDs, meanwhile C/S1/S2 and C/S1/S2/S3 are in the QS regime). Due to uniform morphology, perfect nanostructure, negligible defects, and unique energy level alignment, the C/S1/S2/S3 QS exhibits a high photoluminescence quantum yield of 90.9%, an ultra-long fluorescence lifetime of 215.2 ns, and a slow radiative transition rate. It enables QS-based light-emitting diodes (QS-LEDs) with the state-of-the-art performance, such as high external quantum efficiency (EQE of 22.16%) and excellent stability. Meanwhile, the investigation of charge carrier dynamics reveals the difference between the QD- and QS-LEDs, showing that the charge carriers inside the QS-LEDs need more time to recombine with each other. Based on these findings, this study believes that the emerging QSs can be attractive and efficient light-emitting materials used in lighting and displays.

Effects of Cyclic Adenosine Monophosphate Nanoliposomes on Growth Performance, Gut Development and Microbiota of Broilers

2025-06-23

Li Chen , Li Ping Wang , Huang Sheng +4 more | Animals

This study aimed to investigate the effects of Nano-cAMP on growth performance, gut development, and microbiota composition in broilers. A total of 108 21-day-old yellow-feathered female chicks were randomly divided … This study aimed to investigate the effects of Nano-cAMP on growth performance, gut development, and microbiota composition in broilers. A total of 108 21-day-old yellow-feathered female chicks were randomly divided into three groups with six replicates per group and six chicks per replicate according to the principle of consistent body weight. Experimental treatments included the following: (1) CON group (basal diet), (2) cAMP group (basal diet + 0.02 g/kg cAMP), and (3) Nano-cAMP group (basal diet + 0.37 g/kg Nano-cAMP liposomes). After a 21-day experimental period, results revealed the following: Compared with the CON group, the Nano-cAMP group exhibited a significantly reduced feed-to-gain ratio (p < 0.05). The cAMP group exhibited a significant increase in duodenal index (p < 0.05), whereas the Nano-cAMP group demonstrated greater jejunal villus height (p < 0.05). Both treatment groups showed significant upregulation of cholecystokinin (CCK) and secretin gene expression (p < 0.05). Analysis of alpha-diversity indices (Chao1, Shannon, Simpson) revealed no significant differences in jejunal and cecal microbiota composition between experimental groups (p > 0.05). Notably, the relative abundance of Firmicutes significantly increased (p < 0.05) in the cAMP and Nano-cAMP groups, whereas Proteobacteria, Gemmatimonadota, and Chloroflexi significantly decreased (p< 0.05). The combined relative abundance of three Lactobacillus genera and Bifidobacterium was obviously elevated. Linear discriminant analysis identified Bifidobacterium, Ruminococcus torques group, and uncultured_Thermoanaerobacterales_bacterium as dominant genera in the intestinal tract of Nano-cAMP group. In conclusion, dietary addition of Nano-cAMP promotes jejunal development, modulates appetite hormones mRNA expression, enhances absorption capacity, increases the relative abundance of intestinal probiotics such as Bifidobacterium and cellulose-degrading bacteria such as Ruminococcus torques group, optimizes gut microbiota composition, and ultimately reduces the feed-to-gain ratio in broilers.

Weak Electrostatic Network Structure Improves PbS Quantum Dot Ink Stability

2025-06-22

Jing‐Feng Li , Wei Dong , Zhijian Li +7 more | ACS Applied Materials & Interfaces

PbS quantum dot (QD) ink stability in polar solvents is critical for high-performance solar cell fabrication. However, QD aggregation in such solvents often leads to epitaxial fusion, resulting in trap … PbS quantum dot (QD) ink stability in polar solvents is critical for high-performance solar cell fabrication. However, QD aggregation in such solvents often leads to epitaxial fusion, resulting in trap states that degrade the device performance. Here, we demonstrate a novel strategy for enhancing ink stability by constructing a weak electrostatic network structure on the QD surface, which is cobuilt by hydrogen bonds and π interactions, providing a stable environment that prevents QD aggregation and epitaxial fusion. The optimized surface structure confers an ink film, with a 13% reduction in Urbach energy, a 50% decrease in trap state density, and a 107% prolongation of carrier lifetime, suggesting significantly enhanced carrier transport and extraction capabilities. With this approach, PbS QD solar cells can achieve a power conversion efficiency of 13% and remain stable for over 1000 h without encapsulation when stored in air.

Surface engineering of SnO2 nanoparticles as electron transport layers for efficient quantum dot light-emitting diodes

2025-06-21

Haeil Jung , Jae-Hyung Park , Jiwan Kim | Journal of the Korean Ceramic Society

Giant, non-perturbative tuning of light-matter interaction of embedded quantum dots in semiconducting matrices

2025-06-21

Ming-Chung Wu , Kai‐Chi Hsiao , Chu-Liang Fu +6 more | Advanced Composites and Hybrid Materials

Abstract Embedding quantum dots (QDs) in a solid-state matrix represents a promising hybrid platform that offers great flexibility and tunability. However, the lack of clear underlying designing principle and presence … Abstract Embedding quantum dots (QDs) in a solid-state matrix represents a promising hybrid platform that offers great flexibility and tunability. However, the lack of clear underlying designing principle and presence of large design space make the design process heavily relies on trial-and-error methods. Here we present a new principle that can drastically tailor the light-matter interaction of matrix by matrix-mediated QD interactions. We show that conducting matrices like P3HT can mediate a non-perturbative inter-QD interactions that lead to qualitatively distinct properties, including the enhanced carrier lifetime and enhanced binding energies with increased QD densities, which cannot be explained by conventional perturbative scattering theories and in sharp contrast to independent embedded QDs in an insulating matrix like PMMA. An effective quantum-field-theory is developed, showing qualitative agreement with experiments. Our study serves as a foundation for the predictive design of advanced hybrid materials aimed at optimizing functionalities.

Insights of prototyping Hierarchical bottom-up of optical active materials for multimodal energy coupling and functional biophotonic nano-, microwearable devices

2025-06-20

Sofía Mickaela Martinez , Cecilia S. Tettamanti , María Valeria Amé +2 more | Characterization and Application of Nanomaterials

In this review are developed insights from the current research work to develop the concept of functional materials. This is understood as real modified substrates for varied applications. So, functional … In this review are developed insights from the current research work to develop the concept of functional materials. This is understood as real modified substrates for varied applications. So, functional and modified substrates focused on nanoarchitectures, microcapsules, and devices for new nanotechnologies highlighting life sciences applications were revised. In this context, different types of concepts to proofs of concepts of new materials are shown to develop desired functions. Thus, it was shown that varied chemicals, emitters, pharmacophores, and controlled nano-chemistry were used for the design of nanoplatforms to further increase the sizes of materials. In this regard, the prototyping of materials was discussed, affording how to afford the challenge in the design and fabrication of new materials. Thus, the concept of optical active materials and the generation of a targeted signal through the substrate were developed. Moreover, advanced concepts were introduced, such as the multimodal energy approach by tuning optical coupling from molecules to the nanoscale within complex matter composites. These approaches were based on the confinement of specific optical matter, considering molecular spectroscopics and nano-optics, from where the new concept nominated as metamaterials was generated. In this manner, fundamental and applied research by the design of hierarchical bottom-up materials, controlling molecules towards nanoplatforms and modified substrates, was proposed. Therefore, varied accurate length scales and dimensions were controlled. Finally, it showed proofs of concepts and applications of implantable, portable, and wearable devices from cutting-edge knowledge to the next generation of devices and miniaturized instrumentation.

Tailoring Superlattice Dimensions: A Pathway to Emergent Quantum Functional Devices

2025-06-19

Jingyang Zhang , Zhixue Guo , Bing Wang +2 more | PubMed

Abstract The evolution of materials engineering has been constrained by the limitations inherent in naturally occurring materials. However, superlattices (SLs) with tunable dimensions (0D–3D) have revolutionized this field by enabling … Abstract The evolution of materials engineering has been constrained by the limitations inherent in naturally occurring materials. However, superlattices (SLs) with tunable dimensions (0D–3D) have revolutionized this field by enabling precise control over atomic‐scale periodicity and interfacial interactions, synergistically integrating multifunctional properties from diverse materials. Beyond natural atomic configurations, these engineered structures can achieve unconventional atomic arrangements, thus unlocking unprecedented material capabilities toward emergent quantum functional devices. This review systematically examines recent advancements in SLs’ research, including synthesis methods through physical and chemical approaches tailored to various dimensionalities. A comparative analysis of fabrication techniques and application domains is provided to guide future method selection. Furthermore, emerging applications of SLs in optical modulation, bandgap engineering, photoelectronic conversion, and magnetic property transitions are comprehensively discussed. The advantages and limitations of SLs across dimensions are critically evaluated, followed by proposals for innovative solutions that integrate machine‐learning‐aided design and in situ characterization techniques. This review aims to provide actionable insights for developing next‐generation SL‐based quantum functional devices.

Effect of Nanocrystal Shape on Charge Injection and Transport in CdSe Nanocrystalline Films

2025-06-19

Mrinmoy Roy , Ehsan Rezaie , Štefan Nagy +1 more | Inorganic Chemistry

Understanding of charge transport (CT) in assemblies of quantum confined semiconductor nanocrystals (NCs) is an important prerequisite for their effective exploitation in optoelectronic applications. Here we use spectro-electrochemistry (SEC) to … Understanding of charge transport (CT) in assemblies of quantum confined semiconductor nanocrystals (NCs) is an important prerequisite for their effective exploitation in optoelectronic applications. Here we use spectro-electrochemistry (SEC) to investigate CT in thin films comprising symmetric CdSe quantum dots (QDs) and asymmetric nanorods (NRs) with similar diameters and NR aspect ratios from 1.8 to 6.7. We find that the efficiency and dynamics of CT depends strongly on size and shape of the NCs as well as on the molecular linkers used in the preparation of the films. For films prepared under similar conditions CT is more efficient in NR films than in QD films. This is attributed to the asymmetry of the NRs resulting in formation of large channels within the film, which allow an efficient diffusion of charge-balancing counterions of the electrolyte. When comparing the NR films, the CT is more efficient in films prepared from thicker NRs and NRs with higher aspect ratios.

Epitaxial-Growth SnSe2/SnSe Lateral Heterojunction Boosts Piezocatalytic Degradation of Antibiotics

2025-06-18

Yue Liu , Huanyan Xu , Bo Li | Crystal Growth & Design

Preparation of water-soluble ZnS quantum dots by hydrodynamic cavitation technology and related stability exploration

2025-06-18

Yingying Zhang , Jince Zhang , Taiyu Jin +3 more | Surfaces and Interfaces

Role of Conjugated Structure of Cross-linkers in Patterned QLEDs

2025-06-18

Jung‐Min Kim , Dongho Choi , Namji Lee +4 more | Nano Letters

Direct optical lithography is a promising method for the high-resolution patterning of colloidal quantum dots (CQDs) in optoelectronic devices. However, this approach requires photo-cross-linkers that ensure strong chemical binding without … Direct optical lithography is a promising method for the high-resolution patterning of colloidal quantum dots (CQDs) in optoelectronic devices. However, this approach requires photo-cross-linkers that ensure strong chemical binding without degrading CQD ligands, while also supporting efficient charge transport. In this study, we compare two cross-linkers, 4,4'-thiobisbenzenethiol (TBBT) and biphenyl-4,4'-dithiol (BPDT), to evaluate their impact on CQD optoelectronic performance. Density functional theory (DFT) calculations reveal that the biphenyl structure of BPDT enables greater π-orbital overlap and a narrower bandgap than TBBT, which contains sulfur-conjugated units. As a result, BPDT enhances charge injection, preserves photoluminescence, and improves the external quantum efficiency of patterned CQD light-emitting diodes. These findings provide molecular-level insight into cross-linker design strategies for efficient, high-resolution patterning of CQD-based optoelectronics.

Synthesis of Metastable Wurtzite Cu–In‐Doped ZnS Photocatalysts via Molten Salt Treatment

2025-06-18

Tomohiro Kawase , Yoshio Kobayashi , Haruki Nagakawa | European Journal of Inorganic Chemistry

In this study, we explored the crystallization process of doped ZnS photocatalysts using a molten salt treatment in air. When ZnS‐based photocatalysts with low crystallinity and a zincblende structure were … In this study, we explored the crystallization process of doped ZnS photocatalysts using a molten salt treatment in air. When ZnS‐based photocatalysts with low crystallinity and a zincblende structure were heated in molten salt under conditions of a short holding time at high temperatures, the structure transitioned from zincblende to the metastable wurtzite phase at 600 °C, which is significantly lower than the bulk transition temperature (1020 °C). Furthermore, with a longer holding time, ZnS reverted to the stable zincblende phase. This phenomenon was attributed to the unique crystal growth behavior of the nanoparticles in the molten salt environment. The evaluation of the synthesized photocatalysts revealed that ZnS with a wurtzite structure exhibited particularly high photocatalytic activity. Additionally, Cu and In co‐doping induced visible‐light responsiveness, achieving hydrogen evolution with a higher external quantum efficiency than that of molten‐salt‐treated CdS photocatalysts synthesized in previous studies. The selective formation of nanoparticles with a metastable wurtzite structure or microparticles with a stable zincblende structure could be controlled by varying the holding time at 600 °C. Thus, Cu–In‐doped ZnS photocatalysts may potentially be used as Cd‐free alternative photocatalysts and semiconductor electrode materials.

Surface Defects and Symmetry Breaking Impact on the Photoluminescence of InP Quantum Dots

2025-06-17

Surender Kumar , Caterina Cocchi , Torben Steenbock | Nano Letters

To fully uncover the potential of indium phosphide (InP) quantum dots (QDs) for optoelectronics, it is crucial to understand how surface defects impact their photoluminescence (PL). To address this question, … To fully uncover the potential of indium phosphide (InP) quantum dots (QDs) for optoelectronics, it is crucial to understand how surface defects impact their photoluminescence (PL). To address this question, we investigate the excitonic properties of defective InP QDs using two-component density functional theory and screened configuration interaction singles. In agreement with earlier observations, we identify 3-fold coordinated phosphorus surface atoms, which function as hole traps, as the major contributors to PL. Additionally, we find that electron traps of 3-fold coordinated indium atoms, quenching the band-edge PL, can further contribute to trap PL, if they lie within the single-particle gap. Importantly, our calculations reveal that surface-induced symmetry breaking leads to fundamentally different exciton fine structures in excellent agreement with measurements. This study underscores the significant influence of surface imperfections on InP QD PL and provides a refined framework for interpreting their optical properties.

Unraveling the Nature of Near to Short‐Wave Infrared Stimulated Emission from PbS Nanocrystals under Vanishing Quantum Confinement

2025-06-17

Jan Matthys , Ranjana Yadav , Nastaran Kazemi Tofighi +5 more | Advanced Optical Materials

Abstract Colloidal semiconducting nanocrystals (NCs) present exciting opportunities to realize small footprint integrated lasers and amplifiers and recent reports indicated near‐to short wave infrared optically pumped lasing is possible using … Abstract Colloidal semiconducting nanocrystals (NCs) present exciting opportunities to realize small footprint integrated lasers and amplifiers and recent reports indicated near‐to short wave infrared optically pumped lasing is possible using lead sulfide (PbS) NCs. However, it remains unclear what are the photo‐physical driving forces behind the efficient optical gain. In this work, quantitative and broadband ultrafast infrared spectroscopy is employed on PbS NCs ranging from a regime of strong to vanishing confinement. Modeling the experimental findings, the importance of spectral redshifts induced by structural reorganization is pinpointed, opposed to commonly observed multi‐exciton Coulomb‐type interactions in NCs. Through such a rather uncommon mechanism for optical gain in weakly confined NCs, observed near‐unity occupation gain thresholds are rationalized, next to a a sizable material gain and long gain lifetimes ‐ limited only by bulk defects. Typical shelling with CdS is not able to further improve the gain lifetime, due to an increase in inhomogeneous broadening canceling the needed excited state spectral shifts. These results indicate that a push to relaxed confinement is probably the best route forward to achieve continuous wave infrared lasing in the near future, yet care must be taken to preserve the beneficial role of structural relaxation effects on the surface.

Structural Insights into Giant Core‐Shell Copper Iron Sulfide‐Zinc Sulfide Nanocrystals

2025-06-16

Hridesh Kumar Gupta , Derlin Davis Pulikkottil , Anshu Pandey | Crystal Research and Technology

Abstract CuFeS₂ nanocrystals have emerged as promising candidates for applications in photovoltaics, spintronics, and bioimaging due to their high absorption coefficients and tunable quantum confinement effects. This study focuses on … Abstract CuFeS₂ nanocrystals have emerged as promising candidates for applications in photovoltaics, spintronics, and bioimaging due to their high absorption coefficients and tunable quantum confinement effects. This study focuses on the synthesis and characterisation of giant CuFeS₂/ZnS core/shell nanocrystals. The development of giant core/shell nanocrystals is a significant step toward addressing limitations such as poor luminescence and non‐radiative recombination in CuFeS₂ nanocrystals. A novel ZnS shell growth protocol is employed to passivate surface defects and enhance photostability without introducing toxic heavy metals like cadmium. X‐ray crystallography confirmed the formation of a sharp CuFeS₂/ZnS interface as well as improved crystallinity. Optical analysis reveals a bandgap as low as 0.5 eV, extending the reach of core/shell architectures into the near‐infrared region. Transmission electron microscopy analysis highlights diverse morphologies and a well‐defined core‐shell structure, with an average size of 26 nm and a uniform ZnS shell of ∼3 nm. The study underscores the potential of CuFeS₂/ZnS nanocrystals as environmentally friendly, efficient, and scalable alternatives to traditional heavy‐metal‐based nanocrystals. By overcoming challenges in synthesis, this work introduces a novel class of giant nanocrystals with enhanced optical and structural properties, paving the way for advanced optoelectronic and biomedical applications.

One-pot green synthesis of protein-modified ternary quantum dots

2025-06-16

Yueyue Zhang , Harvey J. M. Hou , Mengting Cao +6 more | Microchimica Acta

Twisted bilayer materials as a promising platform for solid-state qubits

2025-06-16

NULL AUTHOR_ID | Physical Review Letters

Programmable synthesis of atomically precise semiconductor artificial atoms

2025-06-16

Fuyan Ma , Sergei A. Ivanov , Łukasz Dobrzycki +1 more | Nature Synthesis

Electron localization engineering to construct Cu single-atom bridges between g-C3N4 layers for regulating third-order nonlinear optical properties

2025-06-14

Jing Huang , Kangshuai Geng , Yupei Sun +2 more | Nano Today

Suppression of Auger Recombination and Promotion of Carrier Diffusion in Ag(I)-Doped CdSe Nanotetrapods

2025-06-14

Priya Bhandari , Fariyad Ali , Anindya Datta | The Journal of Physical Chemistry C

Design of Zn Chalcogenide Shells for Emissive Ga-Rich In1–XGaXAs Quantum Dots Synthesized in Molten Salts

2025-06-13

Jun Hyuk Chang , Justin C. Ondry , Danial Zangeneh +6 more | ACS Nano

Colloidal quantum dots (QDs) have seen expanded applications in optoelectronics from visible to near-infrared (NIR) wavelengths. However, the options for QDs with bright and size-tunable emission in the NIR region … Colloidal quantum dots (QDs) have seen expanded applications in optoelectronics from visible to near-infrared (NIR) wavelengths. However, the options for QDs with bright and size-tunable emission in the NIR region are mostly limited to heavy-metal-based (Pb, Cd, Hg) semiconductors. Here, Ga-rich In1-XGaXAs QDs with zinc chalcogenide shells are demonstrated as candidates for NIR emitters. Based on new developments in inorganic molten salt chemistry, we synthesized colloidal In1-XGaXAs QDs containing up to 85% gallium with high crystallinity based on Raman and XRD analyses. Zinc selenide and sulfide shells with different morphologies were grown on In1-XGaXAs QDs by controlling the Zn precursor chemistry. Despite the nominally reduced lattice mismatch in the In1-XGaXAs/ZnSe heterostructure, a ZnS shell was found to be a much more effective passivation material: In1-XGaXAs/ZnS core-shell QDs show a photoluminescence quantum yield (PL QY) of about 30% versus 11% for ZnSe shells. Based on the analysis of PL decay and transient absorption (TA) dynamics, we surmise that electron trapping is the major reason for efficiency loss, providing a clear heterostructure design principle for realizing efficient NIR-emitting In1-XGaXAs QDs.

Electric Field Inhomogeneity in Colloidal QD‐LEDs

2025-06-13

Shreyas Srinivasan , Ruiqi Zhang , Mike Dillender +7 more | Advanced Optical Materials

Abstract It is demonstrated that the electroluminescent layer in a colloidal quantum dot light emitting diode (QD‐LED), formed by stochastic methods such as spin‐coating, incorporates morphological thickness inhomogeneities, resulting in … Abstract It is demonstrated that the electroluminescent layer in a colloidal quantum dot light emitting diode (QD‐LED), formed by stochastic methods such as spin‐coating, incorporates morphological thickness inhomogeneities, resulting in local electric field variations. These inhomogeneities can be directly visualized and quantified using confocal micro‐photoluminescence (PL) and micro‐electroluminescence (EL), as showed in QD‐LEDs with stochastically processed InP/ZnSe/ZnS colloidal quantum dots (QDs). Around 5% of the device shows EL darkspots under forward bias and PL hotspots under photoexcitation, with a strong spatial correlation between these features. The PL hotspots (EL darkspots) correspond to thicker regions in the stochastically‐processed QD film. This thickness variation leads to two distinct QD sub‐populations responding differently to optical excitation. Time and energy‐resolved spectral diffusion measurements reveal that most excitons belong to a “more‐mobile” sub‐population with fast energy transfer and short, electric field‐dependent lifetimes, while a smaller fraction belongs to a “less‐mobile” sub‐population with slower energy transfer and longer, electric field‐independent lifetimes. The “less‐mobile” excitons correlate with thicker QD regions. These findings shed light on the local electric field inhomogeneity in QD‐LEDs, offering insights into device operation, possible degradation mechanisms, and strategies for developing stochastically‐processed micro‐QD‐LEDs.

Inorganic Quantum Dots: Synthetic Strategy and Environmental Applications

2025-06-13

Yuanlong Sun , Sushu Zhang , Hui Cai +2 more | ACS ES&T Engineering

Bright white light emitting diodes based on sustainable graphene quantum dots derived from Moringa oleifera leaves as photo-converter layer

2025-06-13

F.S. Abd El-kawy , Sherief Hammad , H. Talaat +2 more | Carbon letters

Abstract The avenue to synthesize eco-friendly and high-performing warm-white light emitting diodes (WLEDs) using quantum-dots for color conversion is challenging. Here, the graphene quantum dots (GQDs) are synthesized from Moringa … Abstract The avenue to synthesize eco-friendly and high-performing warm-white light emitting diodes (WLEDs) using quantum-dots for color conversion is challenging. Here, the graphene quantum dots (GQDs) are synthesized from Moringa oleifera leaves without the need of any organic solvents or reducing agents by a one-pot hydrothermal method and utilized for the design of efficient warm WLEDs. The photoluminescence of the obtained GQDs is found to be red-shifted as the excitation wavelength increases. This is ascribed to an excitation of multiple transitions due to various surface traps related to surface amino and oxygen functionalized groups as revealed from X-ray-photoelectron–spectroscopy and FTIR results. Three different concentrations of GQDs are embedded in polyvinyl-alcohol matrix acting as color-converters for the design of WLED devices. By increasing the GQDs concentration, the color correlated temperatures are tuned from 3804 to 2593 K and the luminous efficacy from 39.3 to 71.69 lm/W. Moreover, the chromaticity coordinates of the devices are shifted from (0.3825, 0.3665) to (0.4807, 0.4478). The brightness of the fabricated devices based on these green-GQDs are comparable with those of warm LEDs prepared from chemically synthesized graphene and carbon dots and can be suitable for indoor lighting applications. Graphical abstract

Quantum Dots Affect Actin Cytoskeleton Reorganization, Resulting in Impaired HeLa and THLE-2 Cell Motility

2025-06-12

Mary Elizabeth Metcalf , Abhishu Chand , Kyoungtae Kim | Micro

Quantum dots (QDs) are nanoparticles with intrinsic fluorescence. Recent studies have found that metal-based QDs often impart toxic effects on the biological systems they interact with. Their undefined limitations have … Quantum dots (QDs) are nanoparticles with intrinsic fluorescence. Recent studies have found that metal-based QDs often impart toxic effects on the biological systems they interact with. Their undefined limitations have offset their potential for biomedical application. Our study aimed to address the research gap regarding QDs’ impacts on the intracellular actin cytoskeleton and the associated structures. Our XTT viability assays revealed that QDs only reduced viability in transformed human liver epithelial (THLE-2) cells, whereas HeLa cells remained viable after QD treatment. We also used confocal microscopy to evaluate the morphological changes in THLE-2 induced by QDs. We further investigated cell protrusion morphology using phalloidin-Alexa488 which selectively labels F-actin. The fluorescent microscopy of this phalloidin label revealed that QD treatment resulted in the redistribution of actin filaments within both THLE-2 and HeLa cells. We also report that the average number of focal adhesions decreased in QD-treated cells. As actin filaments at the cell are peripherally linked to the extracellular matrix via talin and integrin and are thus a crucial component of cell motility, we conducted a migration assay. The migration assay revealed that cell motility was significantly reduced in both THLE-2 and HeLa cells following QD treatment. Our findings establish that the internalization of QDs reduces cell motility by rearranging actin filaments.

Rare-Earth Gadolinium (Gd)-Doped InP Quantum Dots with Excellent Photostability in Liquid Crystal Display Backlight Display

2025-06-12

Ke Wang , Chaoqing Dong , Xiangyi Huang +5 more | The Journal of Physical Chemistry C

Identification of Cosensitizers for Triggering Terbium Emission Enhancement in Zinc Sulfide Nanoparticles

2025-06-12

Nayan Bhunia , S.A. Muhammed Ali , Madhumita Bhar +3 more | ACS Applied Optical Materials

Balancing Charge Injection for Enhanced Efficiency in Inverted InP Quantum Dot Light‐Emitting Diodes

2025-06-11

Hee Jung Kwak , Jaebum Jeong , Collins Kiguye +3 more | Advanced Quantum Technologies

Abstract Indium phosphide (InP) quantum dots (QDs) have emerged as promising candidates for next‐generation display and solid‐state lighting technologies. However, InP‐based quantum dot light‐emitting diodes (QLEDs) using zinc oxide nanoparticles … Abstract Indium phosphide (InP) quantum dots (QDs) have emerged as promising candidates for next‐generation display and solid‐state lighting technologies. However, InP‐based quantum dot light‐emitting diodes (QLEDs) using zinc oxide nanoparticles (ZnO NPs) as the electron transport layer (ETL) suffer from performance degradation due to unbalanced carrier injection. This is mainly caused by the high electron mobility of ZnO, which leads to excessive electron injection into the emissive layer. In this study, Poly(4‐vinylpyridine) (PVPy) is introduced as an electron‐blocking interlayer between the ZnO ETL and the InP‐QD emissive layer to mitigate this imbalance. The insulating nature of PVPy effectively limits electron injection, reducing charge accumulation and enhancing device performance. To further evaluate the role of hole transport layers (HTLs) in conjunction with PVPy, devices incorporating solution‐processed HTLs such as TFB (in p‐xylene), PTAA (in chlorobenzene), and a PTAA–PVK blend are fabricated. A thermally evaporated MoO₃ layer is used as the hole injection layer with Ag as the anode. Devices incorporating the PVPy interlayer consistently outperform those without, confirming the interlayer's role in improving charge balance and overall QLED performance. This strategy provides valuable insight into interface engineering for high‐performance, cadmium‐free QLEDs.