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Azhniuk YM, Lopushansky VV, Solonenko D, Kryshenik VM, Loya VY, Voynarovych IM, Gomonnai AV, Zahn DRT. CdS nanocrystals formed in amorphous GeS2:Cd films by photoenhanced diffusion. APPLIED NANOSCIENCE 2022. [DOI: 10.1007/s13204-021-01778-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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2
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Gull S, Jamil MH, Zhang X, Kwok H, Li G. Stokes Shift in Inorganic Lead Halide Perovskites: Current Status and Perspective. ChemistryOpen 2022; 11:e202100285. [PMID: 35147296 PMCID: PMC8889505 DOI: 10.1002/open.202100285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 12/18/2021] [Indexed: 11/08/2022] Open
Abstract
Inorganic metal halide perovskite system is considered as a promising candidate for applications from display to biomedical industry. Intrinsic inorganic lead halides possess small Stokes shift or self-absorption, providing negative impact for both photo voltaic and biomedical applications. Therefore, the development of an inorganic halide perovskite system with large Stokes shift is a significant venture. This review aims to provide an updated survey of the Stokes shift phenomena in the inorganic lead halide perovskites. The first section focuses about the mechanism, the second section gives different approaches in preparing inorganic perovskites with distinct Stokes shift, while the third section highlights the potential applications in both photovoltaic and biomedical areas. This review provides deep insight about the importance and usefulness of such phenomena in inorganic lead halides, essential for various applications.
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Affiliation(s)
- Sehrish Gull
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong ProvinceCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhenChina
| | - M. Haris Jamil
- College of Electronics and Electrical EngineeringShenzhen UniversityShenzhenChina
| | - Xiuwen Zhang
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong ProvinceCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhenChina
| | - Hoi‐sing Kwok
- State Key Lab of Advanced Displays and Optoelectronics TechnologiesHong Kong University of Science and TechnologyClear Water BayKowloonHong Kong
| | - Guijun Li
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong ProvinceCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhenChina
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3
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Rodosthenous P, Skibinsky-Gitlin ES, Rodriguez-Bolivar S, Califano M, Gomez-Campos FM. Band-like transport in 'green' quantum dot films: the effect of composition and stoichiometry. J Chem Phys 2022; 156:104704. [DOI: 10.1063/5.0078375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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4
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Rodosthenous P, Gómez-Campos FM, Califano M. Tuning the Radiative Lifetime in InP Colloidal Quantum Dots by Controlling the Surface Stoichiometry. J Phys Chem Lett 2020; 11:10124-10130. [PMID: 33191752 DOI: 10.1021/acs.jpclett.0c02752] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
InP nanocrystals exhibit a low photoluminescence quantum yield. As in the case of CdS, this is commonly attributed to their poor surface quality and difficult passivation, which give rise to trap states and negatively affect emission. Hence, the strategies adopted to improve their quantum yield have focused on the growth of shells, to improve passivation and get rid of the surface states. Here, we employ state-of-the-art atomistic semiempirical pseudopotential modeling to isolate the effect of surface stoichiometry from features due to the presence of surface trap states and show that, even with an atomistically perfect surface and an ideal passivation, InP nanostructures may still exhibit very long radiative lifetimes (on the order of tens of microseconds), broad and weak emission, and large Stokes' shifts. Furthermore, we find that all these quantities can be varied by orders of magnitude, by simply manipulating the surface composition, and, in particular, the number of surface P atoms. As a consequence it should be possible to substantially increase the quantum yield in these nanostructures by controlling their surface stoichiometry.
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Affiliation(s)
- Panagiotis Rodosthenous
- Pollard Institute, School of Electronic and Electrical Engineering, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Francisco M Gómez-Campos
- Departamento de Electrónica y Tecnología de Computadores, Facultad de Ciencias, Universidad de Granada, 18071 Granada, Spain
- CITIC-UGR, C/Periodista Rafael Gómez Montero, n 2, Granada E-18071, Spain
| | - Marco Califano
- Pollard Institute, School of Electronic and Electrical Engineering, University of Leeds, Leeds LS2 9JT, United Kingdom
- Bragg Centre for Materials Research, University of Leeds, Leeds LS2 9JT, United Kingdom
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Elibol E, Elibol PS, Çadırcı M, Tutkun N. Improved photoluminescence and monodisperse performance of colloidal CdTe quantum dots with Cannula method. KOREAN J CHEM ENG 2019. [DOI: 10.1007/s11814-019-0243-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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6
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Banski M, Chrzanowski M, Zatryb G, Misiewicz J, Podhorodecki A. Enhanced photoluminescence stability of CdS nanocrystals through a zinc acetate reagent. RSC Adv 2018; 8:25417-25422. [PMID: 35539763 PMCID: PMC9082552 DOI: 10.1039/c8ra03504k] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 06/16/2018] [Indexed: 11/21/2022] Open
Abstract
In this study, the role of a zinc acetate precursor in improving the luminescence stability of purple-emitting CdS nanocrystals is investigated. The oleate-capped core of CdS nanocrystals exhibits intense photodarkening under prolonged UV excitation. From the results of photoluminescence experiments, we can observe that photobleaching is responsible for the degradation of temporal stability, i.e., decline in photoluminescence intensity. Herein, we demonstrate that by adding zinc acetate to the synthesis solution, one can enhance the photoluminescence stability by the complete suppression of the bleaching processes of nanocrystals. We can distinguish between the effects caused by zinc ions and those caused by acetate ligands. Acetate ligands improve the photoluminescence stability of the core of CdS nanocrystals. However, only when zinc acetate is used, the PL stability can be conserved at high excitation power. Simultaneously, we have studied the influence of zinc cations and acetate ligands on the kinetics of nanocrystal growth. The presented results underline the importance of short surface capping ligands and zinc cations in CdS nanocrystal synthesis. This study exhibits a new advantage of exploiting zinc acetate reagents in one-pot nanocrystal synthesis.
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Affiliation(s)
- M Banski
- Department of Experimental Physics, Wroclaw University of Science and Technology Wybrzeze Wyspianskiego 27 50-370 Wroclaw Poland
| | - M Chrzanowski
- Department of Experimental Physics, Wroclaw University of Science and Technology Wybrzeze Wyspianskiego 27 50-370 Wroclaw Poland
| | - G Zatryb
- Department of Experimental Physics, Wroclaw University of Science and Technology Wybrzeze Wyspianskiego 27 50-370 Wroclaw Poland
| | - J Misiewicz
- Department of Experimental Physics, Wroclaw University of Science and Technology Wybrzeze Wyspianskiego 27 50-370 Wroclaw Poland
| | - A Podhorodecki
- Department of Experimental Physics, Wroclaw University of Science and Technology Wybrzeze Wyspianskiego 27 50-370 Wroclaw Poland
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7
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Woodall DL, Tobias AK, Jones M. Resolving carrier recombination in CdS quantum dots: A time-resolved fluorescence study. Chem Phys 2016. [DOI: 10.1016/j.chemphys.2015.10.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Kim D, Yokota H, Shimura K, Nakayama M. Temperature dependence of photoluminescence dynamics of self-assembled monolayers of CdSe quantum dots: the influence of the bound-exciton state. Phys Chem Chem Phys 2014; 15:21051-7. [PMID: 24220232 DOI: 10.1039/c3cp54012j] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We have investigated the temperature dependence of photoluminescence (PL) dynamics of self-assembled monolayers (SAMs) of CdSe quantum dots (QDs). The PL decay profiles become slower with an increase in temperature up to 160 K, contrary to an ordinary behavior due to thermal quenching. Such anomalous temperature dependence of the PL-decay profile is explained using a four-state model which introduces a bound-exciton state into a conventional three-state model consisting of a ground state and two excited states: a lower-lying dark-exciton state and a higher-lying bright-exciton state. Furthermore, it is proposed that the radiative decay time of QDs is strongly influenced by the presence or absence of the bound-exciton state.
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Affiliation(s)
- DaeGwi Kim
- Department of Applied Physics, Graduate School of Engineering, Osaka City University, 3-3-138, Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan.
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Bragas AV, Jais PM, Von Bilderling C. Plasmon-enhanced second harmonic generation in semiconductor quantum dots close to metal nanoparticles. PAPERS IN PHYSICS 2011. [DOI: 10.4279/pip.030002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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11
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Xu X, Zhao Y, Sie EJ, Lu Y, Liu B, Ekahana SA, Ju X, Jiang Q, Wang J, Sun H, Sum TC, Huan CHA, Feng YP, Xiong Q. Dynamics of bound exciton complexes in CdS nanobelts. ACS NANO 2011; 5:3660-9. [PMID: 21449578 DOI: 10.1021/nn2008832] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Intrinsic defects such as vacancies, interstitials, and anti-sites often introduce rich luminescent properties in II-VI semiconductor nanomaterials. A clear understanding of the dynamics of the defect-related excitons is particularly important for the design and optimization of nanoscale optoelectronic devices. In this paper, low-temperature steady-state and time-resolved photoluminescence (PL) spectroscopies have been carried out to investigate the emission of cadmium sulfide (CdS) nanobelts that originates from the radiative recombination of excitons bound to neutral donors (I(2)) and the spatially localized donor-acceptor pairs (DAP), in which the assignment is supported by first principle calculations. Our results verify that the shallow donors in CdS are contributed by sulfur vacancies while the acceptors are contributed by cadmium vacancies. At high excitation intensities, the DAP emission saturates and the PL is dominated by I(2) emission. Beyond a threshold power of approximately 5 μW, amplified spontaneous emission (ASE) of I(2) occurs. Further analysis shows that these intrinsic defects created long-lived (spin triplet) DAP trap states due to spin-polarized Cd vacancies which become saturated at intense carrier excitations.
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Affiliation(s)
- Xinlong Xu
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371
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Ghosh S, Ghosh D, Bag PK, Bhattacharya SC, Saha A. Aqueous synthesis of ZnTe/dendrimer nanocomposites and their antimicrobial activity: implications in therapeutics. NANOSCALE 2011; 3:1139-1148. [PMID: 21218228 DOI: 10.1039/c0nr00610f] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The present strategy proposes a simple and single step aqueous route for synthesizing stable, fluorescent ZnTe/dendrimer nanocomposites with varying dendrimer terminal groups. In these hybrid materials, the fluorescence of the semiconductor combines with the biomimetic properties of the dendrimer making them suitable for various biomedical applications. The ZnTe nanocomposites thus obtained demonstrate bactericidal activity against enteropathogenic bacteria without having toxic effects on the human erythrocytes. The average size of the ZnTe nanoparticles within the dendrimer matrix was in the range of 2.9-6.0 nm, and they have a good degree of crystallinity with a hexagonal crystal phase. The antibacterial activities of the ZnTe/dendrimer nanocomposites (ZnTe DNCs) as well other semiconductor nanocomposites were evaluated against enteropathogenic bacteria including multi-drug resistant Vibrio cholerae serogroup O1 and enterotoxigenic Escherichia coli (ETEC). ZnTe DNCs had significant antibacterial activity against strains of V. cholerae and ETEC with minimum inhibitory concentrations ranging from 64 to 512 μg ml(-1) and minimum bactericidal concentrations ranging from 128 to 1000 μg ml(-1). Thus, the observed results suggest that these water-soluble active nanocomposites have potential for the treatment of enteric diseases like diarrhoea and cholera.
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Affiliation(s)
- S Ghosh
- UGC-DAE Consortium for Scientific Research, Kolkata Centre, III/LB-8 Bidhannagar, Kolkata, 700 098, India
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Li L, She NF, Fei Z, So PK, Wang YZ, Cao LP, Wu AX, Yao ZP. Novel Fluorescent Molecular Clips: Selective Recognition Towards Fe3+ in Aqueous Solution. J Fluoresc 2010; 21:1103-10. [DOI: 10.1007/s10895-010-0784-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2010] [Accepted: 11/25/2010] [Indexed: 10/18/2022]
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14
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Zhang LJ, Shen XC, Liang H, Guo S, Liang ZH. Hot-injection synthesis of highly luminescent and monodisperse CdS nanocrystals using thioacetamide and cadmium source with proper reactivity. J Colloid Interface Sci 2010; 342:236-42. [DOI: 10.1016/j.jcis.2009.10.030] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2009] [Revised: 08/26/2009] [Accepted: 10/13/2009] [Indexed: 10/20/2022]
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15
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Emin S, Sogoshi N, Nakabayashi S, Villeneuve M, Dushkin C. Growth kinetics of CdS quantum dots and synthesis of their polymer nano-composites in CTAB reverse micelles. J Photochem Photobiol A Chem 2009. [DOI: 10.1016/j.jphotochem.2009.07.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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16
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Shen CC, Tseng WL. One-Step Synthesis of White-Light-Emitting Quantum Dots at Low Temperature. Inorg Chem 2009; 48:8689-94. [DOI: 10.1021/ic9006422] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Chien-Chih Shen
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung 804, Taiwan
| | - Wei-Lung Tseng
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung 804, Taiwan
- National Sun Yat-sen University−Kaohsiung Medical University Joint Research Center, Kaohsiung 804, Taiwan
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Zhang L, Aite S, Yu Z. Unique laser-scanning optical microscope for low-temperature imaging and spectroscopy. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2007; 78:083701. [PMID: 17764323 DOI: 10.1063/1.2768924] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Low-temperature optical characterization of single quantum nanostructures can reveal detailed information on structure-dependent properties of these materials. We describe the development of a unique laser-scanning optical microscope capable of low-temperature single molecule/particle imaging and spectroscopy. Making use of the magnification of a microscope objective, the laser- scanning scheme of the present microscope allows for high-repeatability imaging over large sample areas. The microscope is utilized to measure the low-temperature Raman scattering spectra of individual single-walled carbon nanotubes and single molecule fluorescence spectra of conjugated polymers. The developed low-temperature microscope can be applied to study a wide array of nanomaterials at a single particle level.
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Affiliation(s)
- Li Zhang
- Department of Chemistry, City College of New York, New York, NY 10031, USA
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18
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Abstract
Surface effects significantly influence the functionality of semiconductor nanocrystals. A theoretical understanding of these effects requires an atomic-scale description of the surface. We present an atomistic tight-binding theory of the electronic and optical properties of passivated and unpassivated CdS nanocrystals and CdS/ZnS core/shell nanocrystals. Fully passivated dots, with all dangling bonds saturated, have no surface states in the fundamental band gap, and all near-band-edge states are quantum-confined internal states. When surface anion dangling bonds are unpassivated, an anion-derived, narrow (bandwidth 0.05 eV), surface-state band lies 0.5 eV above the valence band edge, and a broader (0.2 eV) band of back-bonded surface states exists in the gap just above the valence band edge. When surface cation dangling bonds are unpassivated, a broad band of mixed surface/internal states exists above the conduction band edge. Partial passivation can push internal levels above the internal levels of a fully passivated dot or into the band gap. Because of this sensitivity to passivation, explicit models for surface effects are needed to describe accurately internal states. Capping the CdS dot with ZnS reduces the effect of the surface on the internal electronic states and optical properties. Six monolayers of ZnS are needed to eliminate the influence of any surface states on the internal states.
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Affiliation(s)
- Garnett W Bryant
- Atomic Physics Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8423, USA.
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Jie JS, Zhang WJ, Jiang Y, Meng XM, Li YQ, Lee ST. Photoconductive characteristics of single-crystal CdS nanoribbons. NANO LETTERS 2006; 6:1887-92. [PMID: 16967996 DOI: 10.1021/nl060867g] [Citation(s) in RCA: 216] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The photoconductive characteristics of CdS single nanoribbons were investigated. The device characteristics, including spectral response, light intensity response, and time response, were studied systematically. It is found that CdS nanoribbon has the response speed substantively faster than those ever reported for conventional film and bulk CdS materials and the size of nanoribbons has a significant influence on the response speed with smaller CdS nanoribbons showing higher response speed. The high photosensitivity and high photoresponse speed are attributable to the large surface-to-volume ratio and high single-crystal quality of CdS nanoribbons and the reduction of recombination barrier in nanostructures. Measurements in a different atmosphere demonstrate that the absorption of ambient gas (mainly oxygen) can significantly change the photosensitivity of CdS nanoribbons through trapping electrons from the nanoribbons.
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Affiliation(s)
- J S Jie
- Center Of Super-Diamond and Advanced Films (COSDAF) and Department of Physics and Materials Science, City University of Hong Kong, Hong Kong Special Administrative Region, China
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Taguchi M, Yagi I, Nakagawa M, Iyoda T, Einaga Y. Photocontrolled Magnetization of CdS-Modified Prussian Blue Nanoparticles. J Am Chem Soc 2006; 128:10978-82. [PMID: 16910695 DOI: 10.1021/ja063461e] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The first photocontrollable magnetic nanoparticles containing CdS and Prussian blue (PB) have been created using reverse micelles as nanoreactors. Photoinduced electron transfer from CdS to PB in the reverse micelle changed the magnetic properties of the composite nanoparticles from ferromagnetic to paramagnetic. The magnetization in the ferromagnetic region below 4 K was substantially decreased after UV light illumination and could be restored almost to its original level by thermal treatment at room temperature. This novel strategy of designing composite nanoparticles containing photoconductive semiconductors and magnetic materials to create photoswitchable magnetic materials may open many possibilities in the development of magneto-optical devices.
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Affiliation(s)
- Minori Taguchi
- Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
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Díaz JG, Planelles J. Theoretical characterization of triangular CdS nanocrystals: a tight-binding approach. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:11278-11284. [PMID: 15568886 DOI: 10.1021/la048353p] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We provide theoretical modeling of the optical spectrum of recently synthesized triangular CdS nanocrystals by means of atomistic tight-binding theory. Both zinc blende and wurtzite structures are considered. Optical properties predicted for triangular prisms are very different from the ones obtained for tetrahedral quantum dots when z-polarized light is employed. In particular, the ground transition is dim for triangular prisms, whereas it is bright and highly intense for tetrahedra. The high sensitivity of the fine optical properties on the quantum dot shape allows us to discriminate between truncated tetrahedra and triangular prisms and also to estimate the thickness of the nanocrystals.
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Affiliation(s)
- J G Díaz
- Departament de Ciències Experimentals, UJI, Box 224, E-12080 Castelló, Spain
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Díaz JG, Planelles J, Bryant GW, Aizpurua J. Tight-Binding Method and Multiband Effective Mass Theory Applied to CdS Nanocrystals: Single-Particle Effects and Optical Spectra Fine Structure. J Phys Chem B 2004. [DOI: 10.1021/jp047658+] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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