1
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Nguyen HA, Hammel BF, Sharp D, Kline J, Schwartz G, Harvey S, Nishiwaki E, Sandeno SF, Ginger DS, Majumdar A, Yazdi S, Dukovic G, Cossairt BM. Colossal Core/Shell CdSe/CdS Quantum Dot Emitters. ACS NANO 2024. [PMID: 39058675 DOI: 10.1021/acsnano.4c06961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/28/2024]
Abstract
Single-photon sources are essential for advancing quantum technologies with scalable integration being a crucial requirement. To date, deterministic positioning of single-photon sources in large-scale photonic structures remains a challenge. In this context, colloidal quantum dots (QDs), particularly core/shell configurations, are attractive due to their solution processability. However, traditional QDs are typically small, about 3 to 6 nm, which restricts their deterministic placement and utility in large-scale photonic devices, particularly within optical cavities. The largest existing core/shell QDs are a family of giant CdSe/CdS QDs, with total diameters ranging from about 20 to 50 nm. Pushing beyond this size limit, we introduce a synthesis strategy for colossal CdSe/CdS QDs, with sizes ranging from 30 to 100 nm, using a stepwise high-temperature continuous injection method. Electron microscopy reveals a consistent hexagonal diamond morphology composed of 12 semipolar {101̅1} facets and one polar (0001) facet. We also identify conditions where shell growth is disrupted, leading to defects, islands, and mechanical instability, which suggest synthetic requirements for growing crystalline particles beyond 100 nm. The stepwise growth of thick CdS shells on CdSe cores enables the synthesis of emissive QDs with long photoluminescence lifetimes of a few microseconds and suppressed blinking at room temperature. Notably, QDs with 80 and 100 CdS monolayers exhibit high single-photon emission purity with second-order photon correlation g(2)(0) values below 0.2.
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Affiliation(s)
- Hao A Nguyen
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Benjamin F Hammel
- Materials Science and Engineering, University of Colorado, Boulder, Colorado 80309-0215, United States
| | - David Sharp
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Jessica Kline
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Griffin Schwartz
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Samantha Harvey
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Emily Nishiwaki
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Soren F Sandeno
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - David S Ginger
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Arka Majumdar
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
- Department of Electrical and Computer Engineering, University of Washington, Seattle, Washington 98195, United States
| | - Sadegh Yazdi
- Materials Science and Engineering, University of Colorado, Boulder, Colorado 80309-0215, United States
- Renewable and Sustainable Energy Institute, University of Colorado, Boulder, Colorado 80309-0215, United States
| | - Gordana Dukovic
- Materials Science and Engineering, University of Colorado, Boulder, Colorado 80309-0215, United States
- Department of Chemistry, University of Colorado, Boulder, Colorado 80309-0215, United States
- Renewable and Sustainable Energy Institute, University of Colorado, Boulder, Colorado 80309-0215, United States
| | - Brandi M Cossairt
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
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2
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Brumberg A, Watkins NE, Diroll BT, Schaller RD. Acceleration of Biexciton Radiative Recombination at Low Temperature in CdSe Nanoplatelets. NANO LETTERS 2022; 22:6997-7004. [PMID: 36018835 DOI: 10.1021/acs.nanolett.2c01791] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Colloidal semiconductor nanocrystals offer bandgap tunability, high photoluminescence quantum yield, and colloidal processing of benefit to optoelectronics, however rapid nonradiative Auger recombination (AR) deleteriously affects device efficiencies at elevated excitation intensities. AR is understood to transition from temperature-dependent behavior in bulk semiconductors to temperature-independent behavior in zero-dimensional quantum dots (QDs) as a result of discretized band structure that facilitates satisfaction of linear momentum conservation. For nanoplatelets (NPLs), two-dimensional morphology renders prediction of photophysical behaviors challenging. Here, we investigate and compare the temperature dependence of excited-stated lifetime and fluence-dependent emission of CdSe NPLs and QDs. For NPLs, upon temperature reduction, biexciton lifetime surprisingly decreases (even becoming shorter lived than trion emission) and emission intensity increases nearly linearly with fluence rather than saturating, consistent with dominance of radiative recombination rather than AR. CdSe NPLs thus differ fundamentally from core-only QDs and foster increased utility of photogenerated excitons and multiexcitons at low temperatures.
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Affiliation(s)
- Alexandra Brumberg
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Nicolas E Watkins
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Benjamin T Diroll
- Center for Nanoscale Materials, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Richard D Schaller
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
- Center for Nanoscale Materials, Argonne National Laboratory, Lemont, Illinois 60439, United States
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3
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Brett MW, Gordon CK, Hardy J, Davis NJLK. The Rise and Future of Discrete Organic-Inorganic Hybrid Nanomaterials. ACS PHYSICAL CHEMISTRY AU 2022; 2:364-387. [PMID: 36855686 PMCID: PMC9955269 DOI: 10.1021/acsphyschemau.2c00018] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Hybrid nanomaterials (HNs), the combination of organic semiconductor ligands attached to nanocrystal semiconductor quantum dots, have applications that span a range of practical fields, including biology, chemistry, medical imaging, and optoelectronics. Specifically, HNs operate as discrete, tunable systems that can perform prompt fluorescence, energy transfer, singlet fission, upconversion, and/or thermally activated delayed fluorescence. Interest in HNs has naturally grown over the years due to their tunability and broad spectrum of applications. This Review presents a brief introduction to the components of HNs, before expanding on the characterization and applications of HNs. Finally, the future of HN applications is discussed.
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4
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Roy D, De CK, Ghosh S, Mukherjee S, Mandal S, Mandal PK. Ultrafast dynamics and ultrasensitive single particle spectroscopy of optically robust core/alloy shell semiconductor quantum dots. Phys Chem Chem Phys 2022; 24:8578-8590. [PMID: 35355030 DOI: 10.1039/d1cp05780d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A "one-pot one-step" synthesis method of Core/Alloy Shell (CAS) quantum dots (QDs) offers the scope of large scale synthesis in a less time consuming, more economical, highly reproducible and high-throughput manner in comparison to "multi-pot multi-step" synthesis for Core/Shell (CS) QDs. Rapid initial nucleation, and smooth & uniform shell growth lead to the formation of a compositionally-gradient alloyed hetero-structure with very significantly reduced interfacial trap density in CAS QDs. Thus, interfacial strain gets reduced in a much smoother manner leading to enhanced confinement for the photo-generated charge carriers in CAS QDs. Convincing proof of alloy-shelling for a CAS QD has been provided from HRTEM images at the single particle level. The band gap could be tuned as a function of composition, temperature, reactivity difference of precursors, etc. and a high PLQY and improved photochemical stability could be achieved for a small sized CAS QD. From the ultrafast exciton dynamics in CdSe and InP CAS QDs, it has been shown that (a) the hot exciton thermalization/relaxation happens in <500 fs, (b) hot electron trapping dynamics occurs within a ∼1 ps time scale, (c) band edge exciton trapping occurs within a 10-25 ps timescale and (d) for CdSe CAS QDs the hot hole gets trapped in about 35 ps. From fast PL decay dynamics, it has been shown that the amplitude of the intermediate time constant can be correlated with the PLQY. A model has been provided to understand these ultrafast to fast exciton dynamical processes. At the ultrasensitive single particle level, unlike CS QDs, CdSe CAS QDs have been shown to exhibit (a) constancy of PLmax (i.e. no bluing) and (b) constancy of PL intensity (i.e. no bleaching) of the single CAS QDs for continuous irradiation for one hour under an air atmosphere. Thus, CAS QDs hold the promise of being a superior optical probe in comparison to CS QDs both at the ensemble and at the single particle level, leading to enhanced flexibility of the CAS QDs towards designing and developing next generation application devices.
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Affiliation(s)
- Debjit Roy
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur, West Bengal, 741246, India.
| | - Chayan K De
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur, West Bengal, 741246, India.
| | - Swarnali Ghosh
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur, West Bengal, 741246, India.
| | - Soumen Mukherjee
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur, West Bengal, 741246, India.
| | - Saptarshi Mandal
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur, West Bengal, 741246, India.
| | - Prasun K Mandal
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur, West Bengal, 741246, India. .,Centre for Advanced Functional Materials, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur, West Bengal, 741246, India
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5
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He Y, Chen J, Liu R, Weng Y, Zhang C, Kuang Y, Wang X, Guo L, Ran X. Suppressed Blinking and Polarization-Dependent Emission Enhancement of Single ZnCdSe/ZnS Dot Coupled with Au Nanorods. ACS APPLIED MATERIALS & INTERFACES 2022; 14:12901-12910. [PMID: 35245021 DOI: 10.1021/acsami.2c00207] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Fluorescent quantum dots (QDs) have attracted extensive attention because of their promising applications in many fields such as quantum optics, optoelectronics, solid-state lighting, and bioimaging. However, photo-blinking, low emission efficiency, and instability are the drawbacks of fluorescent QD-based devices, affecting their optical properties and practical applications. Here, we report suppressed blinking, enhanced radiative rate, and polarization-dependent emission properties of single ZnCdSe/ZnS QDs assembled on the surface of Au nanorods (NRs). We found that the local surface plasmon (LSP) of Au NRs significantly regulates the excitation and emission properties of the composite ZnCdSe/ZnS QD-Au NRs (QD-Au NRs). The average number of photons emitted per unit time from single QD-Au NRs has been significantly enhanced compared with that of single ZnCdSe/ZnS QDs on the coverslip, accompanied by a drastically shortened lifetime and suppressed blinking. According to the experimental and simulation analysis, the photogenerated LSP field of Au NRs remarkably increases the excitation transition and the radiative rates of QD-Au NRs. Although the emission efficiency is slightly increased, the synergetic enhancement of excitation and radiative rates sufficiently competes with the nonradiative process to compensate for the low emission efficiency of QDs and ultimately suppress the photo-blinking of QD-Au NRs. Moreover, the polarization-dependent emission enhancement has also been observed and theoretically analyzed, demonstrating good consistency and confirming the contribution of excitation enhancement. Our findings present a practical strategy to improve the optical properties and stability of single QD-Au NR composite and provide essential information for a deep understanding of the interaction between emitters and the LSP field of metal nanoparticles.
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Affiliation(s)
- Yulu He
- Academy for Advanced Interdisciplinary Studies, State Key Laboratory of Crop Stress Adaptation and Improvement, School of Physics and Electronics, Henan University, Kaifeng 475004, China
| | - Jin Chen
- School of Physics and Electronics, International Joint Research Laboratory of New Energy Materials and Devices of Henan Province, Henan University, Kaifeng 475004, China
| | - Renming Liu
- School of Physics and Electronics, International Joint Research Laboratory of New Energy Materials and Devices of Henan Province, Henan University, Kaifeng 475004, China
| | - Yulong Weng
- Academy for Advanced Interdisciplinary Studies, State Key Laboratory of Crop Stress Adaptation and Improvement, School of Physics and Electronics, Henan University, Kaifeng 475004, China
| | - Cong Zhang
- School of Physics and Electronics, International Joint Research Laboratory of New Energy Materials and Devices of Henan Province, Henan University, Kaifeng 475004, China
| | - Yanmin Kuang
- School of Physics and Electronics, International Joint Research Laboratory of New Energy Materials and Devices of Henan Province, Henan University, Kaifeng 475004, China
| | - Xiaojuan Wang
- School of Physics and Electronics, International Joint Research Laboratory of New Energy Materials and Devices of Henan Province, Henan University, Kaifeng 475004, China
| | - Lijun Guo
- Academy for Advanced Interdisciplinary Studies, State Key Laboratory of Crop Stress Adaptation and Improvement, School of Physics and Electronics, Henan University, Kaifeng 475004, China
| | - Xia Ran
- School of Physics and Electronics, International Joint Research Laboratory of New Energy Materials and Devices of Henan Province, Henan University, Kaifeng 475004, China
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6
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Xu JY, Tong X, Besteiro LV, Li X, Hu C, Liu R, Channa AI, Zhao H, Rosei F, Govorov AO, Wang Q, Wang ZM. Rational synthesis of novel "giant" CuInTeSe/CdS core/shell quantum dots for optoelectronics. NANOSCALE 2021; 13:15301-15310. [PMID: 34490860 DOI: 10.1039/d1nr04199a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
"Giant" core/shell quantum dots (g-QDs) are promising candidates for emerging optoelectronic technologies thanks to their facile structure/composition-tunable optoelectronic properties and outstanding photo-physical/chemical stability. Here, we synthesized a new type of CuInTeSe (CITS)/CdS g-QDs and regulated their optoelectronic properties by controlling the shell thickness. Through increasing the shell thickness, as-prepared g-QDs exhibited tunable red-shifted emission (from 900 to 1200 nm) and prolonged photoluminescence (PL) lifetimes (up to ∼14.0 μs), indicating a formed band structure showing efficient charge separation and transfer, which is further testified by theoretical calculations and ultrafast time-resolved transient absorption (TA) spectroscopy. These CITS/CdS g-QDs with various shell thicknesses can be employed to fabricate photoelectrochemical (PEC) cells, exhibiting improved photoresponse and stability as compared to the bare CITS QD-based devices. The results indicate that the rational design and engineering of g-QDs is very promising for future QD-based optoelectronic technologies.
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Affiliation(s)
- Jing-Yin Xu
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, P. R. China.
| | - Xin Tong
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, P. R. China.
- Yangtze Delta Region Institute (Huzhou), University of Electronic Science and Technology of China, Huzhou 313001, P. R. China
| | - Lucas V Besteiro
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, P. R. China.
- Institut National de la Recherche Scientifique, Centre Énergie, Matériaux et Télécommunications, 1650 Boul. Lionel Boulet, J3X 1S2 Varennes, Québec, Canada
| | - Xin Li
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, P. R. China.
| | - Chenxia Hu
- State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Special Function Materials and Structure Design, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, P. R. China.
| | - Ruitong Liu
- State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Special Function Materials and Structure Design, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, P. R. China.
| | - Ali Imran Channa
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, P. R. China.
| | - Haiguang Zhao
- College of Physics & State Key Laboratory of Bio-Fibers and Eco-Textiles, Qingdao University, No. 308 Ningxia Road, Qingdao 266071, P. R. China
| | - Federico Rosei
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, P. R. China.
- Institut National de la Recherche Scientifique, Centre Énergie, Matériaux et Télécommunications, 1650 Boul. Lionel Boulet, J3X 1S2 Varennes, Québec, Canada
| | | | - Qiang Wang
- State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Special Function Materials and Structure Design, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, P. R. China.
| | - Zhiming M Wang
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, P. R. China.
- Yangtze Delta Region Institute (Huzhou), University of Electronic Science and Technology of China, Huzhou 313001, P. R. China
- Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia, 43600, Bangi, Selangor, Malaysia
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7
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Vonk SW, Heemskerk BAJ, Keitel RC, Hinterding SOM, Geuchies JJ, Houtepen AJ, Rabouw FT. Biexciton Binding Energy and Line width of Single Quantum Dots at Room Temperature. NANO LETTERS 2021; 21:5760-5766. [PMID: 34133188 PMCID: PMC8283756 DOI: 10.1021/acs.nanolett.1c01556] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 06/12/2021] [Indexed: 05/20/2023]
Abstract
Broadening of multiexciton emission from colloidal quantum dots (QDs) at room temperature is important for their use in high-power applications, but an in-depth characterization has not been possible until now. We present and apply a novel spectroscopic method to quantify the biexciton line width and biexciton binding energy of single CdSe/CdS/ZnS colloidal QDs at room temperature. In our method, which we term "cascade spectroscopy", we select emission events from the biexciton cascade and reconstruct their spectrum. The biexciton has an average emission line width of 86 meV on the single-QD scale, similar to that of the exciton. Variations in the biexciton repulsion (Eb = 4.0 ± 3.1 meV; mean ± standard deviation of 15 QDs) are correlated with but are more narrowly distributed than variations in the exciton energy (10.0 meV standard deviation). Using a simple quantum-mechanical model, we conclude that inhomogeneous broadening in our sample is primarily due to variations in the CdS shell thickness.
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Affiliation(s)
- Sander
J. W. Vonk
- Debye
Institute, Utrecht University, Princetonplein 1, 3584 CC Utrecht, The Netherlands
| | - Bart A. J. Heemskerk
- Debye
Institute, Utrecht University, Princetonplein 1, 3584 CC Utrecht, The Netherlands
| | - Robert C. Keitel
- Optical
Materials Engineering Laboratory, ETH Zurich, Leonhardstrasse 21, 8092 Zurich, Switzerland
| | | | - Jaco J. Geuchies
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Arjan J. Houtepen
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Freddy T. Rabouw
- Debye
Institute, Utrecht University, Princetonplein 1, 3584 CC Utrecht, The Netherlands
- Email for F.T.R.:
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8
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Bai X, Purcell-Milton F, Gun'ko YK. Controlled synthesis of luminescent CIZS/ZnS/ZnS core/shell/shell nanoheterostructures. CrystEngComm 2021. [DOI: 10.1039/d1ce00631b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We report a systematic investigation of the influence of reaction temperatures and times on the morphologies and optical properties of resulting CIZS/ZnS/ZnS quantum nanoheterostructures with “giant” ZnS shell (size >10 nm).
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Affiliation(s)
- Xue Bai
- School of Chemistry and CRANN institute, Trinity College Dublin, Dublin 2, Dublin, Ireland
| | - Finn Purcell-Milton
- School of Chemistry and CRANN institute, Trinity College Dublin, Dublin 2, Dublin, Ireland
| | - Yurii K. Gun'ko
- School of Chemistry and CRANN institute, Trinity College Dublin, Dublin 2, Dublin, Ireland
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9
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Long Z, Zhang W, Tian J, Chen G, Liu Y, Liu R. Recent research on the luminous mechanism, synthetic strategies, and applications of CuInS2 quantum dots. Inorg Chem Front 2021. [DOI: 10.1039/d0qi01228a] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
We discuss the synthesis and luminescence mechanisms of CuInS2 QDs, the strategies to improve their luminous performance and their potential application in light-emitting devices, solar energy conversion, and the biomedical field.
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Affiliation(s)
- Zhiwei Long
- National Engineering Research Center for Rare Earth Materials
- General Research Institute for Nonferrous Metals
- Grirem Advanced Materials Co. Ltd
- Beijing
- P. R China
| | - Wenda Zhang
- National Engineering Research Center for Rare Earth Materials
- General Research Institute for Nonferrous Metals
- Grirem Advanced Materials Co. Ltd
- Beijing
- P. R China
| | - Junhang Tian
- National Engineering Research Center for Rare Earth Materials
- General Research Institute for Nonferrous Metals
- Grirem Advanced Materials Co. Ltd
- Beijing
- P. R China
| | - Guantong Chen
- National Engineering Research Center for Rare Earth Materials
- General Research Institute for Nonferrous Metals
- Grirem Advanced Materials Co. Ltd
- Beijing
- P. R China
| | - Yuanhong Liu
- National Engineering Research Center for Rare Earth Materials
- General Research Institute for Nonferrous Metals
- Grirem Advanced Materials Co. Ltd
- Beijing
- P. R China
| | - Ronghui Liu
- National Engineering Research Center for Rare Earth Materials
- General Research Institute for Nonferrous Metals
- Grirem Advanced Materials Co. Ltd
- Beijing
- P. R China
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10
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Tong X, Kong X, Wang C, Zhou Y, Navarro‐Pardo F, Barba D, Ma D, Sun S, Govorov AO, Zhao H, Wang ZM, Rosei F. Optoelectronic Properties in Near-Infrared Colloidal Heterostructured Pyramidal "Giant" Core/Shell Quantum Dots. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2018; 5:1800656. [PMID: 30128262 PMCID: PMC6097093 DOI: 10.1002/advs.201800656] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Revised: 06/01/2018] [Indexed: 05/29/2023]
Abstract
Colloidal heterostructured quantum dots (QDs) are promising candidates for next-generation optoelectronic devices. In particular, "giant" core/shell QDs (g-QDs) can be engineered to exhibit outstanding optical properties and high chemical/photostability for the fabrication of high-performance optoelectronic devices. Here, the synthesis of heterostructured CuInSe x S2-x (CISeS)/CdSeS/CdS g-QDs with pyramidal shape by using a facile two-step method is reported. The CdSeS/CdS shell is demonstrated to have a pure zinc blend phase other than typical wurtzite phase. The as-obtained heterostructured g-QDs exhibit near-infrared photoluminescence (PL) emission (≈830 nm) and very long PL lifetime (in the microsecond range). The pyramidal g-QDs exhibit a quasi-type II band structure with spatial separation of electron-hole wave function, suggesting an efficient exciton extraction and transport, which is consistent with theoretical calculations. These heterostructured g-QDs are used as light harvesters to fabricate a photoelectrochemical cell, exhibiting a saturated photocurrent density as high as ≈5.5 mA cm-2 and good stability under 1 sun illumination (AM 1.5 G, 100 mW cm-2). These results are an important step toward using heterostructured pyramidal g-QDs for prospective applications in solar technologies.
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Affiliation(s)
- Xin Tong
- Institute of Fundamental and Frontier SciencesUniversity of Electronic Science and Technology of ChinaChengdu610054P. R. China
- Institut National de la Recherche ScientifiqueCentre Énergie Matériaux et Télécommunications1650 Boul. Lionel BouletVarennesQCJ3X 1S2Canada
| | - Xiang‐Tian Kong
- Institute of Fundamental and Frontier SciencesUniversity of Electronic Science and Technology of ChinaChengdu610054P. R. China
- Department of Physics and AstronomyOhio UniversityAthensOH45701USA
| | - Chao Wang
- Institut National de la Recherche ScientifiqueCentre Énergie Matériaux et Télécommunications1650 Boul. Lionel BouletVarennesQCJ3X 1S2Canada
| | - Yufeng Zhou
- Institut National de la Recherche ScientifiqueCentre Énergie Matériaux et Télécommunications1650 Boul. Lionel BouletVarennesQCJ3X 1S2Canada
| | - Fabiola Navarro‐Pardo
- Institute of Fundamental and Frontier SciencesUniversity of Electronic Science and Technology of ChinaChengdu610054P. R. China
- Institut National de la Recherche ScientifiqueCentre Énergie Matériaux et Télécommunications1650 Boul. Lionel BouletVarennesQCJ3X 1S2Canada
| | - David Barba
- Institut National de la Recherche ScientifiqueCentre Énergie Matériaux et Télécommunications1650 Boul. Lionel BouletVarennesQCJ3X 1S2Canada
| | - Dongling Ma
- Institut National de la Recherche ScientifiqueCentre Énergie Matériaux et Télécommunications1650 Boul. Lionel BouletVarennesQCJ3X 1S2Canada
| | - Shuhui Sun
- Institute of Fundamental and Frontier SciencesUniversity of Electronic Science and Technology of ChinaChengdu610054P. R. China
- Institut National de la Recherche ScientifiqueCentre Énergie Matériaux et Télécommunications1650 Boul. Lionel BouletVarennesQCJ3X 1S2Canada
| | | | - Haiguang Zhao
- State Key Laboratory and College of PhysicsQingdao UniversityQingdao266071P. R. China
| | - Zhiming M. Wang
- Institute of Fundamental and Frontier SciencesUniversity of Electronic Science and Technology of ChinaChengdu610054P. R. China
| | - Federico Rosei
- Institute of Fundamental and Frontier SciencesUniversity of Electronic Science and Technology of ChinaChengdu610054P. R. China
- Institut National de la Recherche ScientifiqueCentre Énergie Matériaux et Télécommunications1650 Boul. Lionel BouletVarennesQCJ3X 1S2Canada
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11
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Enright MJ, Cossairt BM. Synthesis of tailor-made colloidal semiconductor heterostructures. Chem Commun (Camb) 2018; 54:7109-7122. [DOI: 10.1039/c8cc03498b] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
This feature article provides an account of the various bottom-up and top-down methods that have been developed to prepare colloidal heterostructures and highlights the benefits of a seeded assembly approach for greater control and customizability.
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12
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Roy D, Mandal S, De CK, Kumar K, Mandal PK. Nearly suppressed photoluminescence blinking of small-sized, blue–green–orange–red emitting single CdSe-based core/gradient alloy shell/shell quantum dots: correlation between truncation time and photoluminescence quantum yield. Phys Chem Chem Phys 2018; 20:10332-10344. [DOI: 10.1039/c8cp00952j] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Nearly suppressed PL blinking of small sized CdSe based CGASS QDs.
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Affiliation(s)
- Debjit Roy
- Department of Chemical Sciences
- Indian Institute of Science Education and Research (IISER) Kolkata
- Mohanpur
- India
| | - Saptarshi Mandal
- Department of Chemical Sciences
- Indian Institute of Science Education and Research (IISER) Kolkata
- Mohanpur
- India
| | - Chayan K. De
- Department of Chemical Sciences
- Indian Institute of Science Education and Research (IISER) Kolkata
- Mohanpur
- India
| | - Kaushalendra Kumar
- Department of Chemical Sciences
- Indian Institute of Science Education and Research (IISER) Kolkata
- Mohanpur
- India
| | - Prasun K. Mandal
- Department of Chemical Sciences
- Indian Institute of Science Education and Research (IISER) Kolkata
- Mohanpur
- India
- Centre for Advanced Functional Materials
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13
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Li S, Sun M, Chou JP, Wei J, Xing H, Hu A. First-principles calculations of the electronic properties of SiC-based bilayer and trilayer heterostructures. Phys Chem Chem Phys 2018; 20:24726-24734. [DOI: 10.1039/c8cp03508c] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The tunable Schottky barrier heights and optical absorption efficiency in van der Waals SiC-based heterostructures are investigated.
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Affiliation(s)
- Song Li
- Department of Mechanical and Biomedical Engineering
- City University of Hong Kong
- Hong Kong SAR
- China
| | - Minglei Sun
- School of Mechanical Engineering
- Southeast University
- Nanjing
- China
- Institute of High Performance Computing
| | - Jyh-Pin Chou
- Department of Mechanical and Biomedical Engineering
- City University of Hong Kong
- Hong Kong SAR
- China
| | - Jie Wei
- Department of Mechanical and Biomedical Engineering
- City University of Hong Kong
- Hong Kong SAR
- China
| | - Huaizhong Xing
- Department of Applied Physics and State Key Laboratory for Modification of Chemical Fibers and Polymer Materials
- Donghua University
- Shanghai 201620
- China
| | - Alice Hu
- Department of Mechanical and Biomedical Engineering
- City University of Hong Kong
- Hong Kong SAR
- China
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14
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Montanarella F, Altantzis T, Zanaga D, Rabouw FT, Bals S, Baesjou P, Vanmaekelbergh D, van Blaaderen A. Composite Supraparticles with Tunable Light Emission. ACS NANO 2017; 11:9136-9142. [PMID: 28787121 PMCID: PMC5618141 DOI: 10.1021/acsnano.7b03975] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 08/08/2017] [Indexed: 05/20/2023]
Abstract
Robust luminophores emitting light with broadly tunable colors are desirable in many applications such as light-emitting diode (LED)-based lighting, displays, integrated optoelectronics and biology. Nanocrystalline quantum dots with multicolor emission, from core- and shell-localized excitons, as well as solid layers of mixed quantum dots that emit different colors have been proposed. Here, we report on colloidal supraparticles that are composed of three types of Cd(Se,ZnS) core/(Cd,Zn)S shell nanocrystals with emission in the red, green, and blue. The emission of the supraparticles can be varied from pure to composite colors over the entire visible region and fine-tuned into variable shades of white light by mixing the nanocrystals in controlled proportions. Our approach results in supraparticles with sizes spanning the colloidal domain and beyond that combine versatility and processability with a broad, stable, and tunable emission, promising applications in lighting devices and biological research.
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Affiliation(s)
- Federico Montanarella
- Condensed Matter and Interfaces and Soft Condensed Matter, Debye Institute
for
Nanomaterials Science, Utrecht University, P.O. Box 80000, 3508 TA Utrecht, The Netherlands
| | - Thomas Altantzis
- EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium
| | - Daniele Zanaga
- EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium
| | - Freddy T. Rabouw
- Condensed Matter and Interfaces and Soft Condensed Matter, Debye Institute
for
Nanomaterials Science, Utrecht University, P.O. Box 80000, 3508 TA Utrecht, The Netherlands
| | - Sara Bals
- EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium
| | - Patrick Baesjou
- Condensed Matter and Interfaces and Soft Condensed Matter, Debye Institute
for
Nanomaterials Science, Utrecht University, P.O. Box 80000, 3508 TA Utrecht, The Netherlands
| | - Daniel Vanmaekelbergh
- Condensed Matter and Interfaces and Soft Condensed Matter, Debye Institute
for
Nanomaterials Science, Utrecht University, P.O. Box 80000, 3508 TA Utrecht, The Netherlands
- E-mail:
| | - Alfons van Blaaderen
- Condensed Matter and Interfaces and Soft Condensed Matter, Debye Institute
for
Nanomaterials Science, Utrecht University, P.O. Box 80000, 3508 TA Utrecht, The Netherlands
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15
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Hanson CJ, Hartmann NF, Singh A, Ma X, DeBenedetti WJI, Casson JL, Grey JK, Chabal YJ, Malko AV, Sykora M, Piryatinski A, Htoon H, Hollingsworth JA. Giant PbSe/CdSe/CdSe Quantum Dots: Crystal-Structure-Defined Ultrastable Near-Infrared Photoluminescence from Single Nanocrystals. J Am Chem Soc 2017; 139:11081-11088. [DOI: 10.1021/jacs.7b03705] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Christina J. Hanson
- Materials
Physics and Applications Division: Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Nicolai F. Hartmann
- Materials
Physics and Applications Division: Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Ajay Singh
- Materials
Physics and Applications Division: Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Xuedan Ma
- Materials
Physics and Applications Division: Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | | | - Joanna L. Casson
- Chemistry
Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - John K. Grey
- Department
of Chemistry, The University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - Yves J. Chabal
- Department
of Materials Science and Engineering, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Anton V. Malko
- Department
of Physics, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Milan Sykora
- Chemistry
Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Andrei Piryatinski
- Theoretical
Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Han Htoon
- Materials
Physics and Applications Division: Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Jennifer A. Hollingsworth
- Materials
Physics and Applications Division: Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
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16
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Pietra F, Kirkwood N, De Trizio L, Hoekstra AW, Kleibergen L, Renaud N, Koole R, Baesjou P, Manna L, Houtepen AJ. Ga for Zn Cation Exchange Allows for Highly Luminescent and Photostable InZnP-Based Quantum Dots. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2017; 29:5192-5199. [PMID: 28706347 PMCID: PMC5503176 DOI: 10.1021/acs.chemmater.7b00848] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 06/06/2017] [Indexed: 05/05/2023]
Abstract
In this work, we demonstrate that a preferential Ga-for-Zn cation exchange is responsible for the increase in photoluminescence that is observed when gallium oleate is added to InZnP alloy QDs. By exposing InZnP QDs with varying Zn/In ratios to gallium oleate and monitoring their optical properties, composition, and size, we conclude that Ga3+ preferentially replaces Zn2+, leading to the formation of InZnP/InGaP core/graded-shell QDs. This cation exchange reaction results in a large increase of the QD photoluminescence, but only for InZnP QDs with Zn/In ≥ 0.5. For InP QDs that do not contain zinc, Ga is most likely incorporated only on the quantum dot surface, and a PL enhancement is not observed. After further growth of a GaP shell and a lattice-matched ZnSeS outer shell, the cation-exchanged InZnP/InGaP QDs continue to exhibit superior PL QY (over 70%) and stability under long-term illumination (840 h, 5 weeks) compared to InZnP cores with the same shells. These results provide important mechanistic insights into recent improvements in InP-based QDs for luminescent applications.
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Affiliation(s)
- Francesca Pietra
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Nicholas Kirkwood
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Luca De Trizio
- Department
of Nanochemistry, Istituto Italiano di Tecnologia
(IIT), via Morego, 30, 16163 Genova, Italy
| | - Anne W. Hoekstra
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Lennart Kleibergen
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Nicolas Renaud
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Rolf Koole
- Philips
Lighting, High Tech Campus
44, 5656 AE Eindhoven, The Netherlands
| | - Patrick Baesjou
- Philips
Lighting, High Tech Campus
44, 5656 AE Eindhoven, The Netherlands
- Soft
Condensed Matter, Debye Institute, Utrecht
University, Princetonplein
5, 3584 CC Utrecht, The Netherlands
| | - Liberato Manna
- Department
of Nanochemistry, Istituto Italiano di Tecnologia
(IIT), via Morego, 30, 16163 Genova, Italy
- Kavli
Institute of Nanoscience, Delft University
of Technology, Lorentzweg
1, 2628 CJ Delft, The Netherlands
| | - Arjan J. Houtepen
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
- E-mail:
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17
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Ying W, Mao Y, Wang X, Guo Y, He H, Ye Z, Lee ST, Peng X. Solid Confinement of Quantum Dots in ZIF-8 for Efficient and Stable Color-Conversion White LEDs. CHEMSUSCHEM 2017; 10:1346-1350. [PMID: 28296052 DOI: 10.1002/cssc.201700223] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 03/10/2017] [Indexed: 06/06/2023]
Abstract
The powder form and low photoluminescence quantum yield (PLQY) of fluorescent metal-organic frameworks (MOFs) present a serious obstacle to fabricating high-efficiency film-like lighting devices. Here, we present a facile way to produce thin films of CdSex S1-x /ZnS quantum dots (QDs)@ZIF-8 with high PLQY by encapsulating red, green, and blue CdSex S1-x /ZnS QDs in ZIF-8 through a one-pot solid-confinement conversion process. The QDs@ZIF-8 thin film emits warm white light with good color quality and presents good thermal stability and long-term durability.
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Affiliation(s)
- Wen Ying
- State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, P.R. China
| | - Yiyin Mao
- State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, P.R. China
| | - Xiaobing Wang
- State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, P.R. China
| | - Yi Guo
- State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, P.R. China
| | - Haiping He
- State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, P.R. China
| | - Zhizhen Ye
- State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, P.R. China
| | - Shuit-Tong Lee
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, 199 Ren'ai Road, Suzhou, Jiangsu, 215123, P.R. China
| | - Xinsheng Peng
- State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, P.R. China
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18
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Moro L, Turemis M, Marini B, Ippodrino R, Giardi MT. Better together: Strategies based on magnetic particles and quantum dots for improved biosensing. Biotechnol Adv 2017; 35:51-63. [DOI: 10.1016/j.biotechadv.2016.11.007] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 09/29/2016] [Accepted: 11/27/2016] [Indexed: 12/14/2022]
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19
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Rabouw FT, de Mello Donega C. Excited-State Dynamics in Colloidal Semiconductor Nanocrystals. Top Curr Chem (Cham) 2016; 374:58. [PMID: 27573500 PMCID: PMC5480409 DOI: 10.1007/s41061-016-0060-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 07/23/2016] [Indexed: 11/29/2022]
Abstract
Colloidal semiconductor nanocrystals have attracted continuous worldwide interest over the last three decades owing to their remarkable and unique size- and shape-, dependent properties. The colloidal nature of these nanomaterials allows one to take full advantage of nanoscale effects to tailor their optoelectronic and physical–chemical properties, yielding materials that combine size-, shape-, and composition-dependent properties with easy surface manipulation and solution processing. These features have turned the study of colloidal semiconductor nanocrystals into a dynamic and multidisciplinary research field, with fascinating fundamental challenges and dazzling application prospects. This review focuses on the excited-state dynamics in these intriguing nanomaterials, covering a range of different relaxation mechanisms that span over 15 orders of magnitude, from a few femtoseconds to a few seconds after photoexcitation. In addition to reviewing the state of the art and highlighting the essential concepts in the field, we also discuss the relevance of the different relaxation processes to a number of potential applications, such as photovoltaics and LEDs. The fundamental physical and chemical principles needed to control and understand the properties of colloidal semiconductor nanocrystals are also addressed.
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Affiliation(s)
- Freddy T Rabouw
- Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, PO Box 80000, 3508 TA, Utrecht, The Netherlands.,Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University, PO Box 80000, 3508 TA, Utrecht, The Netherlands.,Optical Materials Engineering Laboratory, ETH Zurich, 8092, Zurich, Switzerland
| | - Celso de Mello Donega
- Condensed Matter and Interfaces, Debye Institute for Nanomaterials Science, Utrecht University, PO Box 80000, 3508 TA, Utrecht, The Netherlands.
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20
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21
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Pietra F, De Trizio L, Hoekstra AW, Renaud N, Prato M, Grozema FC, Baesjou PJ, Koole R, Manna L, Houtepen AJ. Tuning the Lattice Parameter of InxZnyP for Highly Luminescent Lattice-Matched Core/Shell Quantum Dots. ACS NANO 2016; 10:4754-62. [PMID: 27065247 DOI: 10.1021/acsnano.6b01266] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Colloidal quantum dots (QDs) show great promise as LED phosphors due to their tunable narrow-band emission and ability to produce high-quality white light. Currently, the most suitable QDs for lighting applications are based on cadmium, which presents a toxicity problem for consumer applications. The most promising cadmium-free candidate QDs are based on InP, but their quality lags much behind that of cadmium based QDs. This is not only because the synthesis of InP QDs is more challenging than that of Cd-based QDs, but also because the large lattice parameter of InP makes it difficult to grow an epitaxial, defect-free shell on top of such material. Here, we propose a viable approach to overcome this problem by alloying InP nanocrystals with Zn(2+) ions, which enables the synthesis of InxZnyP alloy QDs having lattice constant that can be tuned from 5.93 Å (pure InP QDs) down to 5.39 Å by simply varying the concentration of the Zn precursor. This lattice engineering allows for subsequent strain-free, epitaxial growth of a ZnSezS1-z shell with lattice parameters matching that of the core. We demonstrate, for a wide range of core and shell compositions (i.e., varying x, y, and z), that the photoluminescence quantum yield is maximal (up to 60%) when lattice mismatch is minimal.
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Affiliation(s)
- Francesca Pietra
- Optoelectronic Materials Section, Faculty of Applied Sciences, Delft University of Technology , Julianalaan 136, 2628 BL Delft, The Netherlands
| | - Luca De Trizio
- Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy
| | - Anne W Hoekstra
- Optoelectronic Materials Section, Faculty of Applied Sciences, Delft University of Technology , Julianalaan 136, 2628 BL Delft, The Netherlands
| | - Nicolas Renaud
- Optoelectronic Materials Section, Faculty of Applied Sciences, Delft University of Technology , Julianalaan 136, 2628 BL Delft, The Netherlands
| | - Mirko Prato
- Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy
| | - Ferdinand C Grozema
- Optoelectronic Materials Section, Faculty of Applied Sciences, Delft University of Technology , Julianalaan 136, 2628 BL Delft, The Netherlands
| | - Patrick J Baesjou
- Philips Research Laboratories , High Tech Campus 4, 5656 AE Eindhoven, The Netherlands
- Soft Condensed Matter, Debye Institute, Utrecht University , Princetonplein 5, 3584 CC Utrecht, The Netherlands
| | - Rolf Koole
- Philips Research Laboratories , High Tech Campus 4, 5656 AE Eindhoven, The Netherlands
| | - Liberato Manna
- Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy
- Kavli Institute of Nanoscience, Delft University of Technology , Lorentzweg 1, 2628 CJ Delft, The Netherlands
| | - Arjan J Houtepen
- Optoelectronic Materials Section, Faculty of Applied Sciences, Delft University of Technology , Julianalaan 136, 2628 BL Delft, The Netherlands
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22
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Jia Y, Wang H, Yan Z, Deng L, Dong H, Ma N, Sun D. A facile method for the synthesis of CuInS2–ZnS quantum dots with tunable photoluminescent properties. RSC Adv 2016. [DOI: 10.1039/c6ra14733j] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
CuInS2/CuInS2–ZnS quantum dots showed excellent tunable photoluminescent properties, which demonstrate great potential for practical applications due to their non-toxicity and excellent optical properties.
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Affiliation(s)
- Yihe Jia
- National Center for Materials Service Safety
- University of Science and Technology Beijing
- Beijing 100083
- China
| | - Haicheng Wang
- National Center for Materials Service Safety
- University of Science and Technology Beijing
- Beijing 100083
- China
| | - Zhiran Yan
- National Center for Materials Service Safety
- University of Science and Technology Beijing
- Beijing 100083
- China
| | - Ling Deng
- National Center for Materials Service Safety
- University of Science and Technology Beijing
- Beijing 100083
- China
| | - Hua Dong
- National Center for Materials Service Safety
- University of Science and Technology Beijing
- Beijing 100083
- China
| | - Ning Ma
- College of Materials Science and Chemical Engineering
- Harbin Engineering University
- Harbin 150001
- China
| | - Dongbai Sun
- National Center for Materials Service Safety
- University of Science and Technology Beijing
- Beijing 100083
- China
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23
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Tavakoli MM, Mirfasih MH, Hasanzadeh S, Aashuri H, Simchi A. Surface passivation of lead sulfide nanocrystals with low electron affinity metals: photoluminescence and photovoltaic performance. Phys Chem Chem Phys 2016; 18:12086-92. [DOI: 10.1039/c5cp07987j] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Low electron affinity metals like Cd can annihilate deep trap states and increase the current density, resulting in higher performance.
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Affiliation(s)
- Mohammad Mahdi Tavakoli
- Department of Materials Science and Engineering
- Sharif University of Technology
- 14588 Tehran
- Iran
| | | | - Soheil Hasanzadeh
- Department of Materials Science and Engineering
- Sharif University of Technology
- 14588 Tehran
- Iran
| | - Hossein Aashuri
- Department of Materials Science and Engineering
- Sharif University of Technology
- 14588 Tehran
- Iran
| | - Abdolreza Simchi
- Department of Materials Science and Engineering
- Sharif University of Technology
- 14588 Tehran
- Iran
- Institute for Nanoscience and Nanotechnology
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24
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Rabouw FT, Vaxenburg R, Bakulin AA, van Dijk-Moes RJA, Bakker HJ, Rodina A, Lifshitz E, L Efros A, Koenderink AF, Vanmaekelbergh D. Dynamics of Intraband and Interband Auger Processes in Colloidal Core-Shell Quantum Dots. ACS NANO 2015; 9:10366-76. [PMID: 26389562 DOI: 10.1021/acsnano.5b04491] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Conventional colloidal quantum dots (QDs) suffer from rapid energy losses by nonradiative (Auger) processes, leading to sub-ns lifetimes in all excited states but the lowest-energy single exciton. Suppression of interband Auger decay, such as biexciton Auger recombination, has been achieved with the design of heterostructured core-shell QDs. Auger-like processes are also believed to be responsible for rapid intraband hot-electron cooling in QDs. However, the simultaneous effect of shell growth on interband Auger recombination and intraband hot-electron cooling has not been addressed. Here we investigate how the growth of a CdS shell affects these two relaxation processes in CdSe/CdS core-shell QDs. Using a combination of ultrafast pump-push-probe spectroscopy on the QD ensemble and analysis of the photon statistics from single QDs, we find that Auger losses in the biexciton state are suppressed with increasing shell thickness, while hot-electron cooling remains unaffected. Calculations conducted within an eight-band k·p model confirm the experimental dependence of the biexciton Auger decay on the shell thickness, and provide insights into the factors determining the cooling rate of hot carriers.
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Affiliation(s)
- Freddy T Rabouw
- Condensed Matter and Interfaces, Debye Institute for Nanomaterials Science , Princetonplein 1, 3584 CC Utrecht, The Netherlands
| | - Roman Vaxenburg
- Technion - Israel Institute of Technology , Haifa 32000, Israel
| | - Artem A Bakulin
- Cavendish Laboratory, University of Cambridge , JJ Thomson Avenue, Cambridge CB3 OHE, U.K
- FOM Institute AMOLF , Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - Relinde J A van Dijk-Moes
- Condensed Matter and Interfaces, Debye Institute for Nanomaterials Science , Princetonplein 1, 3584 CC Utrecht, The Netherlands
| | - Huib J Bakker
- FOM Institute AMOLF , Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - Anna Rodina
- Ioffe Institute, Russian Academy of Sciences , 194021 St. Petersburg, Russia
| | - Efrat Lifshitz
- Technion - Israel Institute of Technology , Haifa 32000, Israel
| | | | | | - Daniël Vanmaekelbergh
- Condensed Matter and Interfaces, Debye Institute for Nanomaterials Science , Princetonplein 1, 3584 CC Utrecht, The Netherlands
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25
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Antanovich AV, Prudnikau AV, Melnikau D, Rakovich YP, Chuvilin A, Woggon U, Achtstein AW, Artemyev MV. Colloidal synthesis and optical properties of type-II CdSe-CdTe and inverted CdTe-CdSe core-wing heteronanoplatelets. NANOSCALE 2015; 7:8084-92. [PMID: 25873332 DOI: 10.1039/c4nr07134d] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
We developed colloidal synthesis to investigate the structural and electronic properties of CdSe-CdTe and inverted CdTe-CdSe heteronanoplatelets and experimentally demonstrate that the overgrowth of cadmium selenide or cadmium telluride core nanoplatelets with counterpartner chalcogenide wings leads to type-II heteronanoplatelets with emission energies defined by the bandgaps of the CdSe and CdTe platelets and the characteristic band offsets. The observed conduction and valence band offsets of 0.36 eV and 0.56 eV are in line with theoretical predictions. The presented type-II heteronanoplatelets exhibit efficient spatially indirect radiative exciton recombination with a quantum yield as high as 23%. While the exciton lifetime is strongly prolonged in the investigated type-II 2D systems with respect to 2D type-I systems, the occurring 2D giant oscillator strength (GOST) effect still leads to a fast and efficient exciton recombination. This makes type-II heteronanoplatelets interesting candidates for low threshold lasing applications and photovoltaics.
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Affiliation(s)
- A V Antanovich
- Institute for Physico-Chemical Problems, Belarusian State University, Leningradskaya str., 14, Minsk 220030, Belarus.
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26
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DeVore MS, Stich DG, Keller AM, Ghosh Y, Goodwin PM, Phipps ME, Stewart MH, Cleyrat C, Wilson BS, Lidke DS, Hollingsworth JA, Werner JH. Three dimensional time-gated tracking of non-blinking quantum dots in live cells. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2015; 9338. [PMID: 25932286 DOI: 10.1117/12.2082943] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Single particle tracking has provided a wealth of information about biophysical processes such as motor protein transport and diffusion in cell membranes. However, motion out of the plane of the microscope or blinking of the fluorescent probe used as a label generally limits observation times to several seconds. Here, we overcome these limitations by using novel non-blinking quantum dots as probes and employing a custom 3D tracking microscope to actively follow motion in three dimensions (3D) in live cells. Signal-to-noise is improved in the cellular milieu through the use of pulsed excitation and time-gated detection.
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Affiliation(s)
- Matthew S DeVore
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Dominik G Stich
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Aaron M Keller
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Yagnaseni Ghosh
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Peter M Goodwin
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Mary E Phipps
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Michael H Stewart
- Optical Sciences Division, Code 5600, U.S. Naval Research Laboratory, Washington D.C. 20375, USA
| | - Cédric Cleyrat
- Department of Pathology and Cancer Research and Treatment Center, University of New Mexico, Albuquerque, NM 87131, USA
| | - Bridget S Wilson
- Department of Pathology and Cancer Research and Treatment Center, University of New Mexico, Albuquerque, NM 87131, USA
| | - Diane S Lidke
- Department of Pathology and Cancer Research and Treatment Center, University of New Mexico, Albuquerque, NM 87131, USA
| | - Jennifer A Hollingsworth
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - James H Werner
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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Keller AM, Ghosh Y, DeVore MS, Phipps ME, Stewart MH, Wilson BS, Lidke DS, Hollingsworth JA, Werner JH. 3-Dimensional Tracking of Non-blinking 'Giant' Quantum Dots in Live Cells. ADVANCED FUNCTIONAL MATERIALS 2014; 24:4796-4803. [PMID: 25798080 PMCID: PMC4366348 DOI: 10.1002/adfm.201400349] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
While semiconductor quantum dots (QDs) have been used successfully in numerous single particle tracking (SPT) studies due to their high photoluminescence efficiency, photostability, and broad palette of emission colors, conventional QDs exhibit fluorescence intermittency or 'blinking,' which causes ambiguity in particle trajectory analysis and limits tracking duration. Here, non-blinking 'giant' quantum dots (gQDs) are exploited to study IgE-FcεRI receptor dynamics in live cells using a confocal-based 3D SPT microscope. There is a 7-fold increase in the probability of observing IgE-FcεRI for longer than 1 min using the gQDs compared to commercially available QDs. A time-gated photon-pair correlation analysis is implemented to verify that selected SPT trajectories are definitively from individual gQDs and not aggregates. The increase in tracking duration for the gQDs allows the observation of multiple changes in diffusion rates of individual IgE-FcεRI receptors occurring on long (>1 min) time scales, which are quantified using a time-dependent diffusion coefficient and hidden Markov modeling. Non-blinking gQDs should become an important tool in future live cell 2D and 3D SPT studies, especially in cases where changes in cellular dynamics are occurring on the time scale of several minutes.
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Affiliation(s)
- Aaron M. Keller
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Yagnaseni Ghosh
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Matthew S. DeVore
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Mary E. Phipps
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Michael H. Stewart
- Optical Sciences Division, Code 5600, US Naval Research Laboratory, Washington, D.C. 20375, USA
| | - Bridget S. Wilson
- Department of Pathology and Cancer Research and Treatment Center, University of New Mexico Health Sciences Center, Albuquerque, New Mexico 97131, USA
| | - Diane S. Lidke
- Department of Pathology and Cancer Research and Treatment Center, University of New Mexico Health Sciences Center, Albuquerque, New Mexico 97131, USA
| | - Jennifer A. Hollingsworth
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - James H. Werner
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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28
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Smyder JA, Amori AR, Odoi MY, Stern HA, Peterson JJ, Krauss TD. The influence of continuous vs. pulsed laser excitation on single quantum dot photophysics. Phys Chem Chem Phys 2014; 16:25723-8. [PMID: 24950616 DOI: 10.1039/c4cp01395f] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The impact of pulsed versus continuous wave (cw) laser excitation on the photophysical properties of single quantum dots (QDs) has been investigated in an experiment in which all macroscopic variables are identical except the nature of laser excitation. Pulsed excitation exaggerates the effects of photobleaching, results in a lower probability of long ON fluorescence blinking events, and leads to shorter fluorescence lifetimes with respect to cw excitation at the same wavelength and average intensity. Spectral wandering, biexciton quantum yields, and power law exponents that describe fluorescence blinking are largely insensitive to the nature of laser excitation. These results explicitly illustrate important similarities and differences in fluorescence dynamics between pulsed and cw excitation, enabling more meaningful comparisons between literature reports and aiding in the design of new experiments to mitigate possible influences of high photon flux on QDs.
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Affiliation(s)
- Julie A Smyder
- Departments of Chemistry, University of Rochester, Rochester, New York 14627, USA.
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29
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Mangum BD, Sampat S, Ghosh Y, Hollingsworth JA, Htoon H, Malko AV. Influence of the core size on biexciton quantum yield of giant CdSe/CdS nanocrystals. NANOSCALE 2014; 6:3712-3720. [PMID: 24569861 DOI: 10.1039/c3nr06558h] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We present a systematic study of photoluminescence (PL) emission intensity and biexciton (BX) quantum yields (QYBX) in individual "giant" CdSe/CdS nanocrystals (g-NCs) as a function of g-NC core size and shell thickness. We show that g-NC core size significantly affects QYBX and can be utilized as an effective tuning parameter towards higher QYBX while keeping the total volume of the g-NC constant. Specifically, we observe that small-core (2.2 nm diameter) CdSe/CdS NCs with a volume of ∼200 nm(3) (shell comprises 4 CdS monolayers) show very low average and maximum QYBX's of ∼3 and 7%, respectively. In contrast, same-volume medium-core (3 nm diameter) NCs afford higher average values of ∼10%, while QYBX's of ∼30% are achieved for same-volume large-core (5.5 nm diameter) CdSe/CdS NCs, with some approaching ∼80%. These observations underline the influence of the g-NC core size on the evolution of PL emissive states in multi-shell NCs. Moreover, our study also reveals that the use of long anneal times in the growth of CdS shells plays a critical role in achieving high QYBX.
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Affiliation(s)
- Benjamin D Mangum
- Materials Physics and Applications Division, Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
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30
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Sakamoto M, Inoue K, Saruyama M, So YG, Kimoto K, Okano M, Kanemitsu Y, Teranishi T. Investigation on photo-induced charge separation in CdS/CdTe nanopencils. Chem Sci 2014. [DOI: 10.1039/c4sc00635f] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
CdS/CdTe nanopencils were synthesized via anion exchange and the effect of the geometry on the carrier dynamics was investigated.
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Affiliation(s)
- Masanori Sakamoto
- Institute for Chemical Research
- Kyoto University
- Kyoto 611-0011, Japan
- PRESTO
- Japan Science and Technology Agency (JST)
| | - Koki Inoue
- Graduate School of Pure and Applied Sciences
- University of Tsukuba
- Tsukuba, Japan
| | - Masaki Saruyama
- Graduate School of Pure and Applied Sciences
- University of Tsukuba
- Tsukuba, Japan
| | - Yeong-Gi So
- Department of Materials Science and Engineering
- Graduate School of Engineering and Resource Science
- Akita University
- Akita, Japan
| | - Koji Kimoto
- National Institute for Materials Science (NIMS)
- Tsukuba, Japan
| | - Makoto Okano
- Institute for Chemical Research
- Kyoto University
- Kyoto 611-0011, Japan
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31
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32
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Cui J, Beyler AP, Bischof TS, Wilson MWB, Bawendi MG. Deconstructing the photon stream from single nanocrystals: from binning to correlation. Chem Soc Rev 2014; 43:1287-310. [DOI: 10.1039/c3cs60330j] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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33
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Rabouw FT, Lunnemann P, van Dijk-Moes RJA, Frimmer M, Pietra F, Koenderink AF, Vanmaekelbergh D. Reduced Auger recombination in single CdSe/CdS nanorods by one-dimensional electron delocalization. NANO LETTERS 2013; 13:4884-92. [PMID: 24010869 DOI: 10.1021/nl4027567] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Progress to reduce nonradiative Auger decay in colloidal nanocrystals has recently been made by growing thick shells. However, the physics of Auger suppression is not yet fully understood. Here, we examine the dynamics and spectral characteristics of single CdSe-dot-in-CdS-rod nanocrystals. These exhibit blinking due to charging/discharging, as well as trap-related blinking. We show that one-dimensional electron delocalization into the rod-shaped shell can be as effective as a thick spherical shell at reducing Auger recombination of the negative trion state.
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Affiliation(s)
- Freddy T Rabouw
- Condensed Matter and Interfaces, Debye Institute for Nanomaterials Science , Princetonplein 1, 3584 CC Utrecht, The Netherlands
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34
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Thon SM, Ip AH, Voznyy O, Levina L, Kemp KW, Carey GH, Masala S, Sargent EH. Role of bond adaptability in the passivation of colloidal quantum dot solids. ACS NANO 2013; 7:7680-8. [PMID: 23909748 DOI: 10.1021/nn4021983] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Colloidal quantum dot (CQD) solids are attractive materials for photovoltaic devices due to their low-cost solution-phase processing, high absorption cross sections, and their band gap tunability via the quantum size effect. Recent advances in CQD solar cell performance have relied on new surface passivation strategies. Specifically, cadmium cation passivation of surface chalcogen sites in PbS CQDs has been shown to contribute to lowered trap state densities and improved photovoltaic performance. Here we deploy a generalized solution-phase passivation strategy as a means to improving CQD surface management. We connect the effects of the choice of metal cation on solution-phase surface passivation, film-phase trap density of states, minority carrier mobility, and photovoltaic power conversion efficiency. We show that trap passivation and midgap density of states determine photovoltaic device performance and are strongly influenced by the choice of metal cation. Supported by density functional theory simulations, we propose a model for the role of cations, a picture wherein metals offering the shallowest electron affinities and the greatest adaptability in surface bonding configurations eliminate both deep and shallow traps effectively even in submonolayer amounts. This work illustrates the importance of materials choice in designing a flexible passivation strategy for optimum CQD device performance.
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Affiliation(s)
- Susanna M Thon
- Department of Electrical and Computer Engineering, University of Toronto , 10 King's College Road, Toronto, Ontario, M5S 3G4, Canada
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