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Titus T, Vishnu EK, Garai A, Dutta SK, Sandeep K, Shelke A, Ajithkumar TG, Shaji A, Pradhan N, Thomas KG. Biexciton Emission in CsPbBr 3 Nanocrystals: Polar Facet Matters. NANO LETTERS 2024; 24:10434-10442. [PMID: 39141763 DOI: 10.1021/acs.nanolett.4c01186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/16/2024]
Abstract
The metal halide perovskite nanocrystals exhibit a remarkable tolerance to midgap defect states, resulting in high photoluminescence quantum yields. However, the potential of these nanocrystals for applications in display devices is hindered by the suppression of biexcitonic emission due to various Auger recombination processes. By adopting single-particle photoluminescence spectroscopy, herein, we establish that the biexcitonic quantum efficiency increases with the increase in the number of facets on cesium lead bromide perovskite nanocrystals, progressing from cube to rhombic dodecahedron to rhombicuboctahedron nanostructures. The observed enhancement is attributed mainly to an increase in their surface polarity as the number of facets increases, which reduces the Coulomb interaction of charge carriers, thereby suppressing Auger recombination. Moreover, Auger recombination rate constants obtained from the time-gated photon correlation studies exhibited a discernible decrease as the number of facets increased. These findings underscore the significance of facet engineering in fine-tuning biexciton emission in metal halide perovskite nanocrystals.
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Affiliation(s)
- Timi Titus
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Vithura, Thiruvananthapuram, 695551, India
- Centre for Advanced Materials Research with International Engagement (CAMRIE), Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Vithura, Thiruvananthapuram, 695551, India
| | - E Krishnan Vishnu
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Vithura, Thiruvananthapuram, 695551, India
| | - Arghyadeep Garai
- School of Materials Sciences, Indian Association for the Cultivation of Science, Kolkata, 700032, India
| | - Sumit Kumar Dutta
- School of Materials Sciences, Indian Association for the Cultivation of Science, Kolkata, 700032, India
| | - Kuttysankaran Sandeep
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Vithura, Thiruvananthapuram, 695551, India
- Centre for Advanced Materials Research with International Engagement (CAMRIE), Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Vithura, Thiruvananthapuram, 695551, India
| | - Ankita Shelke
- Central NMR Facility and Physical/Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune, 411008, India
| | - Thalasseril G Ajithkumar
- Central NMR Facility and Physical/Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune, 411008, India
| | - Anil Shaji
- School of Physics, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Vithura, Thiruvananthapuram, 695551, India
| | - Narayan Pradhan
- School of Materials Sciences, Indian Association for the Cultivation of Science, Kolkata, 700032, India
| | - K George Thomas
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Vithura, Thiruvananthapuram, 695551, India
- Centre for Advanced Materials Research with International Engagement (CAMRIE), Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Vithura, Thiruvananthapuram, 695551, India
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2
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Ye J, Gaur D, Mi C, Chen Z, Fernández IL, Zhao H, Dong Y, Polavarapu L, Hoye RLZ. Strongly-confined colloidal lead-halide perovskite quantum dots: from synthesis to applications. Chem Soc Rev 2024; 53:8095-8122. [PMID: 38894687 DOI: 10.1039/d4cs00077c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
Colloidal semiconductor nanocrystals enable the realization and exploitation of quantum phenomena in a controlled manner, and can be scaled up for commercial uses. These materials have become important for a wide range of applications, from ultrahigh definition displays, to solar cells, quantum computing, bioimaging, optical communications, and many more. Over the last decade, lead-halide perovskite nanocrystals have rapidly gained prominence as efficient semiconductors. Although the majority of studies have focused on large nanocrystals in the weak- to intermediate-confinement regime, quantum dots (QDs) in the strongly-confined regime (with sizes smaller than the Bohr diameter, which ranges from 4-12 nm for lead-halide perovskites) offer unique opportunities, including polarized light emission and color-pure, stable luminescence in the region that is unattainable by perovskites with single-halide compositions. In this tutorial review, we bring together the latest insights into this emerging and rapidly growing area, focusing on the synthesis, steady-state optical properties (including exciton fine-structure splitting), and transient kinetics (including hot carrier cooling) of strongly-confined perovskite QDs. We also discuss recent advances in their applications, including single photon emission for quantum technologies, as well as light-emitting diodes. We finish with our perspectives on future challenges and opportunities for strongly-confined QDs, particularly around improving the control over monodispersity and stability, important fundamental questions on the photophysics, and paths forward to improve the performance of perovskite QDs in light-emitting diodes.
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Affiliation(s)
- Junzhi Ye
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK.
| | - Deepika Gaur
- CINBIO, Universidade de Vigo, Materials Chemistry and Physics Group, Department of Physical Chemistry Campus Universitario As Lagoas, Marcosende 36310, Vigo, Spain.
| | - Chenjia Mi
- Department of Chemistry and Biochemistry, The University of Oklahoma, Norman, Oklahoma 73019, USA
| | - Zijian Chen
- Centre for Intelligent and Biomimetic Systems, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 440305, China
| | - Iago López Fernández
- CINBIO, Universidade de Vigo, Materials Chemistry and Physics Group, Department of Physical Chemistry Campus Universitario As Lagoas, Marcosende 36310, Vigo, Spain.
| | - Haitao Zhao
- Centre for Intelligent and Biomimetic Systems, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 440305, China
| | - Yitong Dong
- Department of Chemistry and Biochemistry, The University of Oklahoma, Norman, Oklahoma 73019, USA
| | - Lakshminarayana Polavarapu
- CINBIO, Universidade de Vigo, Materials Chemistry and Physics Group, Department of Physical Chemistry Campus Universitario As Lagoas, Marcosende 36310, Vigo, Spain.
| | - Robert L Z Hoye
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK.
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3
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Lei H, Lv L, Zhou X, Liu S, Zhu M, Wang H, Qin H, Fang Q, Peng X. Weakly Confined Semiconductor Nanocrystals Excel in Photochemical and Optoelectronic Properties: Evidence from Single-Dot Studies. J Am Chem Soc 2024; 146:21948-21959. [PMID: 39075033 DOI: 10.1021/jacs.4c06993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/31/2024]
Abstract
Single-molecule spectroscopy offers state-resolved measurements on charge-transfer reactions of single semiconductor nanocrystals, leading to the discovery of up to six single-charge transfer reactions with seven transient states for single CdSe/CdS core/shell nanocrystals with water (or oxygen) as the hole (or electron) acceptors. Kinetic rates of three photoinduced single-hole transfer reactions decrease significantly upon increasing the number of excess electrons in a nanocrystal, mainly due to efficient Auger nonradiative recombination of the charged single excitons. Conversely, the kinetic rates of three single-electron transfer reactions of an unexcited nanocrystal increase proportionally to the number of excess electrons in it. Results here reveal that charge-transfer reactions of nanocrystals, at the center of nearly all their functions, could only be deciphered at a state-resolved level on a single nanocrystal. Size-dependent studies validate the weakly confined semiconductor nanocrystals, instead of strongly confined ones (quantum dots), as optimal candidates for photochemical and optoelectronic applications.
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Affiliation(s)
- Haixin Lei
- Key Laboratory of Excited-State Materials of Zhejiang Province, and Department of Chemistry, Zhejiang University, Hangzhou 310058, China
| | - Liulin Lv
- Key Laboratory of Excited-State Materials of Zhejiang Province, and Department of Chemistry, Zhejiang University, Hangzhou 310058, China
| | - Xionglin Zhou
- Key Laboratory of Excited-State Materials of Zhejiang Province, and Department of Chemistry, Zhejiang University, Hangzhou 310058, China
| | - Shaojie Liu
- Key Laboratory of Excited-State Materials of Zhejiang Province, and Department of Chemistry, Zhejiang University, Hangzhou 310058, China
| | - Meiyi Zhu
- Key Laboratory of Excited-State Materials of Zhejiang Province, and Department of Chemistry, Zhejiang University, Hangzhou 310058, China
| | - Huifeng Wang
- Key Laboratory of Excited-State Materials of Zhejiang Province, and Department of Chemistry, Zhejiang University, Hangzhou 310058, China
| | - Haiyan Qin
- Key Laboratory of Excited-State Materials of Zhejiang Province, and Department of Chemistry, Zhejiang University, Hangzhou 310058, China
| | - Qun Fang
- Key Laboratory of Excited-State Materials of Zhejiang Province, and Department of Chemistry, Zhejiang University, Hangzhou 310058, China
| | - Xiaogang Peng
- Key Laboratory of Excited-State Materials of Zhejiang Province, and Department of Chemistry, Zhejiang University, Hangzhou 310058, China
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4
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Panda MK, Acharjee D, Mahato AB, Ghosh S. Facet Dependent Photoluminescence Blinking from Perovskite Nanocrystals. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2311559. [PMID: 38546015 DOI: 10.1002/smll.202311559] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 03/06/2024] [Indexed: 08/17/2024]
Abstract
Photoluminescence (PL) blinking of nanoparticles, while detrimental to their imaging applications, may benefit next-generation displays if the blinking is precisely controlled by reversible electron/hole injections from an external source. Considerable efforts are made to create well-characterized charged excitons within nanoparticles through electrochemical charging, which has led to enhanced control over PL-blinking in numerous instances. Manipulating the photocharging/discharging rates in nanoparticles by surface engineering can represent a straightforward method for regulating their blinking behaviors, an area largely unexplored for perovskite nanocrystals (PNCs). This work shows facet engineering leading to different morphologies of PNCs characterized by distinct blinking patterns. For instance, examining the PL intensity trajectories of single PNCs, representing the instantaneous photon count rate over time, reveals that the OFF-state population significantly increases as the number of facets increases from six to twenty-six. This study suggests that extra-faceted PNCs, owing to their polar facets and expanded surface area, render them more susceptible to photocharging, which results in larger OFF-state populations. Furthermore, the fluorescence correlation spectroscopy (FCS) study unveils that the augmented propensity for photocharging in extra-faceted PNCs can also originate from their greater tendency to form complexes with neighboring molecules.
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Affiliation(s)
- Mrinal Kanti Panda
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), An OCC of Homi Bhabha National Institute (HBNI), Khurda, Odisha, 752050, India
| | - Debopam Acharjee
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), An OCC of Homi Bhabha National Institute (HBNI), Khurda, Odisha, 752050, India
| | - Asit Baran Mahato
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), An OCC of Homi Bhabha National Institute (HBNI), Khurda, Odisha, 752050, India
| | - Subhadip Ghosh
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), An OCC of Homi Bhabha National Institute (HBNI), Khurda, Odisha, 752050, India
- Center for Interdisciplinary Sciences (CIS), National Institute of Science Education and Research (NISER), An OCC of Homi Bhabha National Institute (HBNI), Khurda, Odisha, 752050, India
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5
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Bassani CL, van Anders G, Banin U, Baranov D, Chen Q, Dijkstra M, Dimitriyev MS, Efrati E, Faraudo J, Gang O, Gaston N, Golestanian R, Guerrero-Garcia GI, Gruenwald M, Haji-Akbari A, Ibáñez M, Karg M, Kraus T, Lee B, Van Lehn RC, Macfarlane RJ, Mognetti BM, Nikoubashman A, Osat S, Prezhdo OV, Rotskoff GM, Saiz L, Shi AC, Skrabalak S, Smalyukh II, Tagliazucchi M, Talapin DV, Tkachenko AV, Tretiak S, Vaknin D, Widmer-Cooper A, Wong GCL, Ye X, Zhou S, Rabani E, Engel M, Travesset A. Nanocrystal Assemblies: Current Advances and Open Problems. ACS NANO 2024; 18:14791-14840. [PMID: 38814908 DOI: 10.1021/acsnano.3c10201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2024]
Abstract
We explore the potential of nanocrystals (a term used equivalently to nanoparticles) as building blocks for nanomaterials, and the current advances and open challenges for fundamental science developments and applications. Nanocrystal assemblies are inherently multiscale, and the generation of revolutionary material properties requires a precise understanding of the relationship between structure and function, the former being determined by classical effects and the latter often by quantum effects. With an emphasis on theory and computation, we discuss challenges that hamper current assembly strategies and to what extent nanocrystal assemblies represent thermodynamic equilibrium or kinetically trapped metastable states. We also examine dynamic effects and optimization of assembly protocols. Finally, we discuss promising material functions and examples of their realization with nanocrystal assemblies.
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Affiliation(s)
- Carlos L Bassani
- Institute for Multiscale Simulation, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Greg van Anders
- Department of Physics, Engineering Physics, and Astronomy, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - Uri Banin
- Institute of Chemistry and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Dmitry Baranov
- Division of Chemical Physics, Department of Chemistry, Lund University, SE-221 00 Lund, Sweden
| | - Qian Chen
- University of Illinois, Urbana, Illinois 61801, USA
| | - Marjolein Dijkstra
- Soft Condensed Matter & Biophysics, Debye Institute for Nanomaterials Science, Utrecht University, 3584 CC Utrecht, The Netherlands
| | - Michael S Dimitriyev
- Department of Polymer Science and Engineering, University of Massachusetts, Amherst, Massachusetts 01003, USA
- Department of Materials Science and Engineering, Texas A&M University, College Station, Texas 77843, USA
| | - Efi Efrati
- Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100, Israel
- James Franck Institute, The University of Chicago, Chicago, Illinois 60637, USA
| | - Jordi Faraudo
- Institut de Ciencia de Materials de Barcelona (ICMAB-CSIC), Campus de la UAB, E-08193 Bellaterra, Barcelona, Spain
| | - Oleg Gang
- Department of Chemical Engineering, Columbia University, New York, New York 10027, USA
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, USA
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Nicola Gaston
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Department of Physics, The University of Auckland, Auckland 1142, New Zealand
| | - Ramin Golestanian
- Max Planck Institute for Dynamics and Self-Organization (MPI-DS), 37077 Göttingen, Germany
- Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford OX1 3PU, UK
| | - G Ivan Guerrero-Garcia
- Facultad de Ciencias de la Universidad Autónoma de San Luis Potosí, 78295 San Luis Potosí, México
| | - Michael Gruenwald
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Amir Haji-Akbari
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06511, USA
| | - Maria Ibáñez
- Institute of Science and Technology Austria (ISTA), 3400 Klosterneuburg, Austria
| | - Matthias Karg
- Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Tobias Kraus
- INM - Leibniz-Institute for New Materials, 66123 Saarbrücken, Germany
- Saarland University, Colloid and Interface Chemistry, 66123 Saarbrücken, Germany
| | - Byeongdu Lee
- X-ray Science Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Reid C Van Lehn
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53717, USA
| | - Robert J Macfarlane
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA
| | - Bortolo M Mognetti
- Center for Nonlinear Phenomena and Complex Systems, Université Libre de Bruxelles, 1050 Brussels, Belgium
| | - Arash Nikoubashman
- Leibniz-Institut für Polymerforschung Dresden e.V., 01069 Dresden, Germany
- Institut für Theoretische Physik, Technische Universität Dresden, 01069 Dresden, Germany
| | - Saeed Osat
- Max Planck Institute for Dynamics and Self-Organization (MPI-DS), 37077 Göttingen, Germany
| | - Oleg V Prezhdo
- Department of Chemistry, University of Southern California, Los Angeles, CA 90089, USA
- Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089, USA
| | - Grant M Rotskoff
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
| | - Leonor Saiz
- Department of Biomedical Engineering, University of California, Davis, California 95616, USA
| | - An-Chang Shi
- Department of Physics & Astronomy, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - Sara Skrabalak
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, USA
| | - Ivan I Smalyukh
- Department of Physics and Chemical Physics Program, University of Colorado, Boulder, Colorado 80309, USA
- International Institute for Sustainability with Knotted Chiral Meta Matter, Hiroshima University, Higashi-Hiroshima City 739-0046, Japan
| | - Mario Tagliazucchi
- Universidad de Buenos Aires, Ciudad Universitaria, C1428EHA Ciudad Autónoma de Buenos Aires, Buenos Aires 1428 Argentina
| | - Dmitri V Talapin
- Department of Chemistry, James Franck Institute and Pritzker School of Molecular Engineering, The University of Chicago, Chicago, Illinois 60637, USA
- Center for Nanoscale Materials, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Alexei V Tkachenko
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Sergei Tretiak
- Theoretical Division and Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - David Vaknin
- Iowa State University and Ames Lab, Ames, Iowa 50011, USA
| | - Asaph Widmer-Cooper
- ARC Centre of Excellence in Exciton Science, School of Chemistry, University of Sydney, Sydney, New South Wales 2006, Australia
- The University of Sydney Nano Institute, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Gerard C L Wong
- Department of Bioengineering, University of California, Los Angeles, California 90095, USA
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA
- Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles, CA 90095, USA
- California NanoSystems Institute, University of California, Los Angeles, CA 90095, USA
| | - Xingchen Ye
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, USA
| | - Shan Zhou
- Department of Nanoscience and Biomedical Engineering, South Dakota School of Mines and Technology, Rapid City, South Dakota 57701, USA
| | - Eran Rabani
- Department of Chemistry, University of California and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- The Raymond and Beverly Sackler Center of Computational Molecular and Materials Science, Tel Aviv University, Tel Aviv 69978, Israel
| | - Michael Engel
- Institute for Multiscale Simulation, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Alex Travesset
- Iowa State University and Ames Lab, Ames, Iowa 50011, USA
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Yang C, Li Y, Hou X, Zhang M, Zhang G, Li B, Guo W, Han X, Bai X, Li J, Chen R, Qin C, Hu J, Xiao L, Jia S. Conversion of Photoluminescence Blinking Types in Single Colloidal Quantum Dots. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2309134. [PMID: 38150666 DOI: 10.1002/smll.202309134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 11/29/2023] [Indexed: 12/29/2023]
Abstract
Almost all colloidal quantum dots (QDs) exhibit undesired photoluminescence (PL) blinking, which poses a significant obstacle to their use in numerous luminescence applications. An in-depth study of the blinking behavior, along with the associated mechanisms, can provide critical opportunities for fabricating high-quality QDs for diverse applications. Here the blinking of a large series of colloidal QDs is investigated with different surface ligands, particle sizes, shell thicknesses, and compositions. It is found that the blinking behavior of single alloyed CdSe/ZnS QDs with a shell thickness of up to 2 nm undergoes an irreversible conversion from Auger-blinking to band-edge carrier blinking (BC-blinking). Contrastingly, single perovskite QDs with particle sizes smaller than their Bohr diameters exhibit reversible conversion between BC-blinking and more pronounced Auger-blinking. Changes in the effective trapping sites under different excitation conditions are found to be responsible for the blinking type conversions. Additionally, changes in shell thickness and particle size of QDs have a significant effect on the blinking type conversions due to altered wavefunction overlap between excitons and effective trapping sites. This study elucidates the discrepancies in the blinking behavior of various QD samples observed in previous reports and provides deeper understanding of the mechanisms underlying diverse types of blinking.
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Affiliation(s)
- Changgang Yang
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Yang Li
- School of Physics and Optoelectronic Engineering, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, China
- Research Institute of Intelligent Sensing, Zhejiang Lab, Hangzhou, 311100, China
| | - Xiaoqi Hou
- School of Chemistry and Material Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, China
| | - Mi Zhang
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Guofeng Zhang
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Bin Li
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Wenli Guo
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Xue Han
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Xiuqing Bai
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Jialu Li
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Ruiyun Chen
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Chengbing Qin
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Jianyong Hu
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Liantuan Xiao
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Suotang Jia
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
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7
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Wang Z, Tang J, Han J, Xia J, Ma T, Chen XW. Bright Nonblinking Photoluminescence with Blinking Lifetime from a Nanocavity-Coupled Quantum Dot. NANO LETTERS 2024; 24:1761-1768. [PMID: 38261791 DOI: 10.1021/acs.nanolett.3c04661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2024]
Abstract
Colloidal quantum dots (QDs) are excellent luminescent nanomaterials for many optoelectronic applications. However, photoluminescence blinking has limited their practical use. Coupling QDs to plasmonic nanostructures shows potential in suppressing blinking. However, the underlying mechanism remains unclear and debated, hampering the development of bright nonblinking dots. Here, by deterministically coupling a QD to a plasmonic nanocavity, we clarify the mechanism and demonstrate unprecedented single-QD brightness. In particular, we report for the first time that a blinking QD could obtain nonblinking photoluminescence with a blinking lifetime through coupling to the nanocavity. We show that the plasmon-enhanced radiative decay outcompetes the nonradiative Auger process, enabling similar quantum yields for charged and neutral excitons in the same dot. Meanwhile, we demonstrate a record photon detection rate of 17 MHz from a colloidal QD, indicating an experimental photon generation rate of more than 500 MHz. These findings pave the way for ultrabright nonblinking QDs, benefiting diverse QD-based applications.
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Affiliation(s)
- Zhiyuan Wang
- School of Physics, Wuhan National Laboratory for Optoelectronics, Institute for Quantum Science and Engineering and Hubei Key Laboratory of Gravitation and Quantum Physics, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Jianwei Tang
- School of Physics, Wuhan National Laboratory for Optoelectronics, Institute for Quantum Science and Engineering and Hubei Key Laboratory of Gravitation and Quantum Physics, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
- Wuhan Institute of Quantum Technology, Wuhan 430206, P. R. China
| | - Jiahao Han
- School of Physics, Wuhan National Laboratory for Optoelectronics, Institute for Quantum Science and Engineering and Hubei Key Laboratory of Gravitation and Quantum Physics, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Juan Xia
- School of Physics, Wuhan National Laboratory for Optoelectronics, Institute for Quantum Science and Engineering and Hubei Key Laboratory of Gravitation and Quantum Physics, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Tianzi Ma
- School of Physics, Wuhan National Laboratory for Optoelectronics, Institute for Quantum Science and Engineering and Hubei Key Laboratory of Gravitation and Quantum Physics, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Xue-Wen Chen
- School of Physics, Wuhan National Laboratory for Optoelectronics, Institute for Quantum Science and Engineering and Hubei Key Laboratory of Gravitation and Quantum Physics, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
- Wuhan Institute of Quantum Technology, Wuhan 430206, P. R. China
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8
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Lee T, Lee M, Seo H, Kim M, Chun B, Kwak J. Top-Emitting Quantum Dot Light-Emitting Diodes: Theory, Optimization, and Application. SMALL METHODS 2024; 8:e2300266. [PMID: 37183298 DOI: 10.1002/smtd.202300266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/10/2023] [Indexed: 05/16/2023]
Abstract
The superior optical properties of colloidal quantum dots (QDs) have garnered significant broad interest from academia and industry owing to their successful application in self-emitting QD-based light-emitting diodes (QLEDs). In particular, active research is being conducted on QLEDs with top-emission device architectures (TQLEDs) owing to their advantages such as easy integration with conventional backplanes, high color purity, and excellent light extraction. However, due to the complicated optical phenomena and their highly sensitive optoelectrical properties to experimental variations, TQLEDs cannot be optimized easily for practical use. This review summarizes previous studies that have investigated top-emitting device structures and discusses ways to advance the performance of TQLEDs. First, theories relevant to the optoelectrical properties of TQLEDs are introduced. Second, advancements in device optimization are presented, where the underlying theories for each are considered. Finally, multilateral strategies for TQLEDs to enable their wider application to advanced industries are discussed. This work believes that this review can provide valuable insights for realizing commercial TQLEDs applicable to a broad range of applications.
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Affiliation(s)
- Taesoo Lee
- Department of Electrical and Computer Engineering, Inter-university Semiconductor Research Center, and Soft Foundry Institute, Seoul National University, Seoul, 08826, Republic of Korea
| | - Minhyung Lee
- Department of Electrical and Computer Engineering, Inter-university Semiconductor Research Center, and Soft Foundry Institute, Seoul National University, Seoul, 08826, Republic of Korea
| | - Hansol Seo
- Department of Electrical and Computer Engineering, Inter-university Semiconductor Research Center, and Soft Foundry Institute, Seoul National University, Seoul, 08826, Republic of Korea
| | - Minjun Kim
- Department of Electrical and Computer Engineering, Inter-university Semiconductor Research Center, and Soft Foundry Institute, Seoul National University, Seoul, 08826, Republic of Korea
| | - Beomsoo Chun
- Department of Electrical and Computer Engineering, Inter-university Semiconductor Research Center, and Soft Foundry Institute, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jeonghun Kwak
- Department of Electrical and Computer Engineering, Inter-university Semiconductor Research Center, and Soft Foundry Institute, Seoul National University, Seoul, 08826, Republic of Korea
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9
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Azadinia M, Chun P, Lyu Q, Cotella G, Aziz H. Differences in Electron and Hole Injection and Auger Recombination between Red, Green, and Blue CdSe-Based Quantum Dot Light Emitting Devices. ACS NANO 2024; 18:1485-1495. [PMID: 38175971 DOI: 10.1021/acsnano.3c07999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2024]
Abstract
Despite the significant progress that has been made in recent years in improving the performance of quantum dot light-emitting devices (QLEDs), the effect of charge imbalance and excess carriers on excitons in red (R) vs green (G) vs blue (B) QLEDs has not been compared or systematically studied. In this work we study the effect of changing the electron (e)/hole (h) supply ratio in the QDs emissive layer (EML) in CdSe-based R-, G-, and B-QLEDs with inverted structure in order to identify the type of excess carriers and investigate their effect on the electroluminescence performance of QLEDs of each color. Results show that in R-QLEDs, the e/h ratio in the EML is >1, whereas in G- and B-QLEDs, the e/h ratio is <1 with charge balance conditions being significantly worse in the case of B-QLEDs. Transient photoluminescence (PL) and steady state PL measurements show that, compared to electrons, holes lead to a stronger Auger quenching effect. Transient electroluminescence (TrEL) results indicate that Auger quenching leads to a gradual decline in the EL performance of the QLEDs after a few microseconds, with a stronger effect observed for positive charging versus negative charging. The results provide insights into the differences in the efficiency behavior of R-, G-, and B-QLEDs and uncover the role of excess holes and poor charge balance in the lower efficiency and EL stability of B-QLEDs.
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Affiliation(s)
- Mohsen Azadinia
- Department of Electrical and Computer Engineering and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada
| | - Peter Chun
- Ottawa IC Laboratory, Huawei Canada, 19 Allstate Parkway, Markham, Ontario L3R 5B4, Canada
| | - Quan Lyu
- Ipswich Research Centre, Huawei Technologies Research & Development (U.K.) Ltd., Phoenix House (B55), Adastral Park, Ipswich, IP5 3RE, U.K
| | - Giovanni Cotella
- Ipswich Research Centre, Huawei Technologies Research & Development (U.K.) Ltd., Phoenix House (B55), Adastral Park, Ipswich, IP5 3RE, U.K
| | - Hany Aziz
- Department of Electrical and Computer Engineering and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada
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10
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Ghorbani A, Chen J, Chun P, Lyu Q, Cotella G, Aziz H. Changes in Hole and Electron Injection under Electrical Stress and the Rapid Electroluminescence Loss in Blue Quantum-Dot Light-Emitting Devices. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2304580. [PMID: 37653596 DOI: 10.1002/smll.202304580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 08/17/2023] [Indexed: 09/02/2023]
Abstract
Blue quantum dot light-emitting devices (QLEDs) suffer from fast electroluminescence (EL) loss when under electrical bias. Here, it is identified that the fast EL loss in blue QLEDs is not due to a deterioration in the photoluminescence quantum yield of the quantum dots (QDs), contrary to what is commonly believed, but rather arises primarily from changes in charge injection overtime under the bias that leads to a deterioration in charge balance. Measurements on hole-only and electron-only devices show that hole injection into blue QDs increases over time whereas electron injection decreases. Results also show that the changes are associated with changes in hole and electron trap densities. The results are further verified using QLEDs with blue and red QDs combinations, capacitance versus voltage, and versus time characteristics of the blue QLEDs. The changes in charge injection are also observed to be partially reversible, and therefore using pulsed current instead of constant current bias for driving the blue QLEDs leads to an almost 2.5× longer lifetime at the same initial luminance. This work systematically investigates the origin of blue QLEDs EL loss and provides insights for designing improved blue QDs paving the way for QLEDs technology commercialization.
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Affiliation(s)
- Atefeh Ghorbani
- Department of Electrical and Computer Engineering and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada
| | - Junfei Chen
- Department of Electrical and Computer Engineering and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada
- Institute of Optoelectronics Technology, Beijing Jiaotong University, Beijing, 100044, China
| | - Peter Chun
- Ottawa IC Laboratory, Huawei Canada, 19 Allstate Parkway, Markham, Ontario, L3R 5B4, Canada
| | - Quan Lyu
- Ipswich Research Centre, Huawei Technologies Research & Development (UK) Ltd., Phoenix House (B55), Adastral Park, Ipswich, IP5 3RE, UK
| | - Giovanni Cotella
- Ipswich Research Centre, Huawei Technologies Research & Development (UK) Ltd., Phoenix House (B55), Adastral Park, Ipswich, IP5 3RE, UK
| | - Hany Aziz
- Department of Electrical and Computer Engineering and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada
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11
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Yoshioka M, Yamauchi M, Tamai N, Masuo S. Single-Photon Emission from Organic Dye Molecules Adsorbed on a Quantum Dot via Energy Transfer. NANO LETTERS 2023; 23:11548-11554. [PMID: 38063468 DOI: 10.1021/acs.nanolett.3c03279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2023]
Abstract
Single-photon emissions from individual emitters are crucial in fundamental science and quantum information technologies. Multichromophoric systems, comprising multiple dyes, can exhibit single-photon emissions through efficient annihilation between the excited states; however, exploring this phenomenon in complex systems remains a challenge. In this study, we investigated the photon statistics of emissions from multiple perylene bisimide (PBI) dyes adsorbed onto the surface of CdSe/ZnS quantum dots (QDs). When multiple PBIs were simultaneously excited by both direct excitation and energy transfer from the QD, multiphoton emissions from the PBIs were observed. Conversely, when the QDs were selectively excited, multiple PBIs exhibiting single-photon emission through energy transfer from the QDs to the PBIs were found. These results highlight the intriguing interplay between multichromophoric systems and QDs, offering valuable insights into the development of efficient single-photon sources in quantum information technologies.
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Affiliation(s)
- Miyu Yoshioka
- Department of Applied Chemistry for Environment, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo 669-1330, Japan
| | - Mitsuaki Yamauchi
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Naoto Tamai
- Department of Chemistry, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo 669-1330, Japan
| | - Sadahiro Masuo
- Department of Applied Chemistry for Environment, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo 669-1330, Japan
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12
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Chen Y, Wang R, Kuang Y, Bian Y, Chen F, Shen H, Chi Z, Ran X, Guo L. Suppressed Auger recombination and enhanced emission of InP/ZnSe/ZnS quantum dots through inner shell manipulation. NANOSCALE 2023; 15:18920-18927. [PMID: 37975758 DOI: 10.1039/d3nr05010f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2023]
Abstract
Understanding the influence of the inner shell on fluorescence blinking and exciton dynamics is essential to promote the optical performances of InP-based quantum dots (QDs). Here, the fluorescence blinking, exciton dynamics, second-order correlation function g2(τ), and ultrafast carrier dynamics of InP/ZnSe/ZnS QDs regulated by the inner ZnSe shell thickness varying from 2 to 7 monolayers (MLs) were systematically investigated. With an inner ZnSe shell thickness of 5 MLs, the photoluminescence quantum yield (PL QY) can reach 98% due to the suppressed blinking and increased probability of multiphoton emission. The exciton dynamics of InP/ZnSe/ZnS QDs with different inner shells indicates that two decay components of neural excitons and charged trions are competitive to affect the photon emission behavior. The probability density distributions of the ON and OFF state duration in the blinking traces demonstrate an effective manipulation of the inner ZnSe shell in the non-radiative processes via defect passivation. Accordingly, the radiative recombination dominates the exciton deactivation and the non-radiative Auger recombination rate is remarkably reduced, leading to a QY close to unity and a high PL stability for InP/ZnSe/ZnS QDs with 5 MLs of the ZnSe shell. These results provide insights into the photophysical mechanism of InP-based QDs and are significant for developing novel semiconductor PL core/shell QDs.
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Affiliation(s)
- Yaru Chen
- School of Physics and Electronics, International Joint Research Laboratory of New Energy Materials and Devices of Henan Province, Henan University, Kaifeng, 475004, China.
| | - Rixin Wang
- 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.
| | - Yangyang Bian
- Key Laboratory for Special Functional Materials of Ministry of Education National & Local Joint Engineering Research Center for High-Efficiency Display and Lighting Technology Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng, 475004, P. R. China
| | - Fei Chen
- Key Laboratory for Special Functional Materials of Ministry of Education National & Local Joint Engineering Research Center for High-Efficiency Display and Lighting Technology Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng, 475004, P. R. China
| | - Huaibin Shen
- Key Laboratory for Special Functional Materials of Ministry of Education National & Local Joint Engineering Research Center for High-Efficiency Display and Lighting Technology Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng, 475004, P. R. China
| | - Zhen Chi
- School of Physics and Electronics, International Joint Research Laboratory of New Energy Materials and Devices of Henan Province, 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.
| | - Lijun Guo
- 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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13
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He S, Tang X, Deng Y, Yin N, Jin W, Lu X, Chen D, Wang C, Sun T, Chen Q, Jin Y. Anomalous efficiency elevation of quantum-dot light-emitting diodes induced by operational degradation. Nat Commun 2023; 14:7785. [PMID: 38012136 PMCID: PMC10682488 DOI: 10.1038/s41467-023-43340-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Accepted: 11/08/2023] [Indexed: 11/29/2023] Open
Abstract
Quantum-dot light-emitting diodes promise a new generation of high-performance and solution-processed electroluminescent light sources. Understanding the operational degradation mechanisms of quantum-dot light-emitting diodes is crucial for their practical applications. Here, we show that quantum-dot light-emitting diodes may exhibit an anomalous degradation pattern characterized by a continuous increase in electroluminescent efficiency upon electrical stressing, which deviates from the typical decrease in electroluminescent efficiency observed in other light-emitting diodes. Various in-situ/operando characterizations were performed to investigate the evolutions of charge dynamics during the efficiency elevation, and the alterations in electric potential landscapes in the active devices. Furthermore, we carried out selective peel-off-and-rebuild experiments and depth-profiling analyses to pinpoint the critical degradation site and reveal the underlying microscopic mechanism. The results indicate that the operation-induced efficiency increase results from the degradation of electron-injection capability at the electron-transport layer/cathode interface, which in turn leads to gradually improved charge balance. Our work provides new insights into the degradation of red quantum-dot light-emitting diodes and has far-reaching implications for the design of charge-injection interfaces in solution-processed light-emitting diodes.
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Affiliation(s)
- Siyu He
- Key Laboratory of Excited-State Materials of Zhejiang Province, State Key Laboratory of Silicon Materials, Department of Chemistry, Zhejiang University, Hangzhou, China
| | - Xiaoqi Tang
- Key Laboratory of Excited-State Materials of Zhejiang Province, State Key Laboratory of Silicon Materials, Department of Chemistry, Zhejiang University, Hangzhou, China
| | - Yunzhou Deng
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, International Research Center for Advanced Photonics, Zhejiang University, Hangzhou, China.
- Cavendish Laboratory, University of Cambridge, Cambridge, UK.
| | - Ni Yin
- i-Lab, CAS Key Laboratory of Nanophotonic Materials and Devices, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou, China
| | - Wangxiao Jin
- Key Laboratory of Excited-State Materials of Zhejiang Province, State Key Laboratory of Silicon Materials, Department of Chemistry, Zhejiang University, Hangzhou, China
| | - Xiuyuan Lu
- Key Laboratory of Excited-State Materials of Zhejiang Province, State Key Laboratory of Silicon Materials, Department of Chemistry, Zhejiang University, Hangzhou, China
| | - Desui Chen
- Key Laboratory of Excited-State Materials of Zhejiang Province, State Key Laboratory of Silicon Materials, Department of Chemistry, Zhejiang University, Hangzhou, China
| | - Chenyang Wang
- Key Laboratory of Excited-State Materials of Zhejiang Province, State Key Laboratory of Silicon Materials, Department of Chemistry, Zhejiang University, Hangzhou, China
| | - Tulai Sun
- Center for Electron Microscopy, State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology and College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, China
| | - Qi Chen
- i-Lab, CAS Key Laboratory of Nanophotonic Materials and Devices, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou, China.
| | - Yizheng Jin
- Key Laboratory of Excited-State Materials of Zhejiang Province, State Key Laboratory of Silicon Materials, Department of Chemistry, Zhejiang University, Hangzhou, China.
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14
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Jia S, Hu M, Gu M, Ma J, Li D, Xiang G, Liu P, Wang K, Servati P, Ge WK, Sun XW. Optimizing ZnO-Quantum Dot Interface with Thiol as Ligand Modification for High-Performance Quantum Dot Light-Emitting Diodes. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023:e2307298. [PMID: 37972284 DOI: 10.1002/smll.202307298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 10/16/2023] [Indexed: 11/19/2023]
Abstract
As the electron transport layer in quantum dot light-emitting diodes (QLEDs), ZnO suffers from excessive electrons that lead to luminescence quenching of the quantum dots (QDs) and charge-imbalance in QLEDs. Therefore, the interplay between ZnO and QDs requires an in-depth understanding. In this study, DFT and COSMOSL simulations are employed to investigate the effect of sulfur atoms on ZnO. Based on the simulations, thiol ligands (specifically 2-hydroxy-1-ethanethiol) to modify the ZnO nanocrystals are adopted. This modification alleviates the excess electrons without causing any additional issues in the charge injection in QLEDs. This modification strategy proves to be effective in improving the performance of red-emitting QLEDs, achieving an external quantum efficiency of over 23% and a remarkably long lifetime T95 of >12 000 h at 1000 cd m-2 . Importantly, the relationship between ZnO layers with different electronic properties and their effect on the adjacent QDs through a single QD measurement is investigated. These findings show that the ZnO surface defects and electronic properties can significantly impact the device performance, highlighting the importance of optimizing the ZnO-QD interface, and showcasing a promising ligand strategy for the development of highly efficient QLEDs.
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Affiliation(s)
- Siqi Jia
- Institute of Nanoscience and Applications, and Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
- Institute of Advanced Displays and Imaging, Henan Academy of Sciences, Zhengzhou, 450046, China
- Peng Cheng Laboratory, Shenzhen, 518038, China
| | - Menglei Hu
- Institute of Nanoscience and Applications, and Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
- Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Mi Gu
- Institute of Nanoscience and Applications, and Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Jingrui Ma
- Institute of Nanoscience and Applications, and Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Depeng Li
- Institute of Nanoscience and Applications, and Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Guohong Xiang
- Institute of Nanoscience and Applications, and Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Pai Liu
- Institute of Nanoscience and Applications, and Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
- Shenzhen Key Laboratory of Deep Subwavelength Scale Photonics, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Kai Wang
- Institute of Nanoscience and Applications, and Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Peyman Servati
- Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Wei Kun Ge
- Institute of Nanoscience and Applications, and Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Xiao Wei Sun
- Institute of Nanoscience and Applications, and Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
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15
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Trotsiuk L, Muravitskaya A, Movsesyan A, Ramanenka A, Prudnikau A, Antanovich A, Lesnyak V, Gaponenko SV, Govorov AO. Nonclassical Mechanism of Metal-Enhanced Photoluminescence of Quantum Dots. NANO LETTERS 2023; 23:8524-8531. [PMID: 37704574 DOI: 10.1021/acs.nanolett.3c02250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/15/2023]
Abstract
Metal-enhanced photoluminescence is able to provide a robust signal even from a single emitter and is promising in applications in biosensors and optoelectronic devices. However, its realization with semiconductor nanocrystals (e.g., quantum dots, QDs) is not always straightforward due to the hidden and not fully described interactions between plasmonic nanoparticles and an emitter. Here, we demonstrate nonclassical enhancement (i.e., not a conventional electromagnetic mechanism) of the QD photoluminescence at nonplasmonic conditions and correlate it with the charge exchange processes in the system, particularly with high efficiency of the hot-hole generation in gold nanoparticles and the possibility of their transfer to QDs. The hole injection returns a QD from a charged nonemitting state caused by hole trapping by surface and/or interfacial traps into an uncharged emitting state, which leads to an increased photoluminescence intensity. These results open new insights into metal-enhanced photoluminescence, showing the importance of the QD surface states in this process.
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Affiliation(s)
- Liudmila Trotsiuk
- B.I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, Minsk 220072, Belarus
| | - Alina Muravitskaya
- Department of Physics and Mathematics, University of Hull, Cotthingham Road, HU6 7RX Hull, U.K
| | - Artur Movsesyan
- Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China, Chengdu 610054, China
- Department of Physics and Astronomy and Nanoscale and Quantum Phenomena Institute, Ohio University, Athens, Ohio 45701, United States
| | - Andrei Ramanenka
- B.I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, Minsk 220072, Belarus
| | | | | | | | - Sergey V Gaponenko
- B.I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, Minsk 220072, Belarus
| | - Alexander O Govorov
- Department of Physics and Astronomy and Nanoscale and Quantum Phenomena Institute, Ohio University, Athens, Ohio 45701, United States
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16
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Zhang X, Xiao S, Guo Z, Yuan B, Wang X, Zhang S, Shi Y, Xing G, He T, Chen R. Improving the Five-Photon Absorption from Core-Shell Perovskite Nanocrystals. J Phys Chem Lett 2023; 14:7581-7590. [PMID: 37590125 DOI: 10.1021/acs.jpclett.3c01809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/19/2023]
Abstract
It is necessary to improve the action cross section (η × σn) of high-order multiphoton absorption (MPA) for fundamental research and practical applications. Herein, the core-shell FAPbBr3/CsPbBr3 nanocrystals (NCs) were constructed, and fluorescence induced by up to five-photon absorption was observed. The value of η × σ5 reaches 8.64 × 10-139 cm10 s4 photon-4 nm-3 at 2300 nm, which is nearly an order of magnitude bigger than that of the core-only NCs. It is found that the increased dielectric constant promotes modulation of MPA effects, addressing the electronic distortion in high-order nonlinear behaviors through the local field effect. Meanwhile, the quasi-type-II band alignment suppresses the biexciton Auger recombination, ensuring the stronger MPA induced fluorescence. In addition, the core-shell structure can not only reduce the defect density but also promote the nonradiative energy transfer though the antenna-like effect. This work provides a new avenue for the exploitation of high-performance multiphoton excited nanomaterials for future photonic integration.
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Affiliation(s)
- Xuanyu Zhang
- Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Shuyu Xiao
- College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
| | - Zhihang Guo
- College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
| | - Baozhen Yuan
- Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Xiongbin Wang
- Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Samo Zhang
- Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Yueqing Shi
- Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Guichuan Xing
- The Institute of Applied Physics and Materials Engineering, University of Macau, Avenida da Universidade, Taipa, Macau 519000, China
| | - Tingchao He
- College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
| | - Rui Chen
- Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
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17
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Armstrong ZT, Forlano KM, Roy CR, Bohlmann Kunz M, Farrell K, Pan D, Wright JC, Jin S, Zanni MT. Spatial Heterogeneity of Biexcitons in Two-Dimensional Ruddlesden-Popper Lead Iodide Perovskites. J Am Chem Soc 2023; 145:18568-18577. [PMID: 37565990 DOI: 10.1021/jacs.3c05533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/12/2023]
Abstract
Quantum confinement in two-dimensional (2D) Ruddlesden-Popper (RP) perovskites leads to the formation of stable quasi-particles, including excitons and biexcitons, the latter of which may enable lasing in these materials. Due to their hybrid organic-inorganic structures and the solution phase synthesis, microcrystals of 2D RP perovskites can be quite heterogeneous, with variations in excitonic and biexcitonic properties between crystals from the same synthesis and even within individual crystals. Here, we employ one- and two-quantum two-dimensional white-light microscopy to systematically study the spatial variations of excitons and biexcitons in microcrystals of a series of 2D RP perovskites BA2MAn-1PbnI3n+1 (n = 2-4, BA= butylammonium, MA = methylammonium). We find that the average biexciton binding energy of around 60 meV is essentially independent of the perovskite layer thickness (n). We also resolve spatial variations of the exciton and biexciton energies on micron length scales within individual crystals. By comparing the one-quantum and two-quantum spectra at each pixel, we conclude that biexcitons are more sensitive to their environments than excitons. These results shed new light on the ways disorder can modify the energetic landscape of excitons and biexcitons in RP perovskites and how biexcitons can be used as a sensitive probe of the microscopic environment of a semiconductor.
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Affiliation(s)
- Zachary T Armstrong
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Kristel M Forlano
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Chris R Roy
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Miriam Bohlmann Kunz
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Kieran Farrell
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Dongxu Pan
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - John C Wright
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Song Jin
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Martin T Zanni
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
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18
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Frenkel N, Scharf E, Lubin G, Levi A, Panfil YE, Ossia Y, Planelles J, Climente JI, Banin U, Oron D. Two Biexciton Types Coexisting in Coupled Quantum Dot Molecules. ACS NANO 2023; 17:14990-15000. [PMID: 37459645 PMCID: PMC10416571 DOI: 10.1021/acsnano.3c03921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 07/12/2023] [Indexed: 08/09/2023]
Abstract
Coupled colloidal quantum dot molecules (CQDMs) are an emerging class of nanomaterials, manifesting two coupled emission centers and thus introducing additional degrees of freedom for designing quantum-dot-based technologies. The properties of multiply excited states in these CQDMs are crucial to their performance as quantum light emitters, but they cannot be fully resolved by existing spectroscopic techniques. Here we study the characteristics of biexcitonic species, which represent a rich landscape of different configurations essentially categorized as either segregated or localized biexciton states. To this end, we introduce an extension of Heralded Spectroscopy to resolve the different biexciton species in the prototypical CdSe/CdS CQDM system. By comparing CQDMs with single quantum dots and with nonfused quantum dot pairs, we uncover the coexistence and interplay of two distinct biexciton species: A fast-decaying, strongly interacting biexciton species, analogous to biexcitons in single quantum dots, and a long-lived, weakly interacting species corresponding to two nearly independent excitons. The two biexciton types are consistent with numerical simulations, assigning the strongly interacting species to two excitons localized at one side of the quantum dot molecule and the weakly interacting species to excitons segregated to the two quantum dot molecule sides. This deeper understanding of multiply excited states in coupled quantum dot molecules can support the rational design of tunable single- or multiple-photon quantum emitters.
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Affiliation(s)
- Nadav Frenkel
- Department
of Physics of Complex Systems, Weizmann
Institute of Science, Rehovot 7610001, Israel
| | - Einav Scharf
- Institute
of Chemistry and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Gur Lubin
- Department
of Physics of Complex Systems, Weizmann
Institute of Science, Rehovot 7610001, Israel
| | - Adar Levi
- Institute
of Chemistry and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Yossef E. Panfil
- Institute
of Chemistry and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Yonatan Ossia
- Institute
of Chemistry and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Josep Planelles
- Departament
de Quimica Fisica i Analitica, Universitat
Jaume I, E-12080 Castello de la Plana, Spain
| | - Juan I. Climente
- Departament
de Quimica Fisica i Analitica, Universitat
Jaume I, E-12080 Castello de la Plana, Spain
| | - Uri Banin
- Institute
of Chemistry and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Dan Oron
- Department
of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 76100, Israel
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19
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Vonk SJW, Rabouw FT. Biexciton Blinking in CdSe-Based Quantum Dots. J Phys Chem Lett 2023:5353-5361. [PMID: 37276380 DOI: 10.1021/acs.jpclett.3c00437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Experiments on single colloidal quantum dots (QDs) have revealed temporal fluctuations in the emission efficiency of the single-exciton state. These fluctuations, often termed "blinking", are caused by opening/closing of charge-carrier traps and/or charging/discharging of the QD. In the regime of strong optical excitation, multiexciton states are formed. The emission efficiencies of multiexcitons are lower because of Auger processes, but a quantitative characterization is challenging. Here, we quantify fluctuations of the biexciton efficiency for single CdSe/CdS/ZnS core-shell QDs. We find that the biexciton efficiency "blinks" significantly. The additional electron due to charging of a QD accelerates Auger recombination by a factor of 2 compared to the neutral biexciton, while opening/closing of a charge-carrier trap leads to an increase of the nonradiative recombination rate by a factor of 4. To understand the fast rate of trap-assisted recombination, we propose a revised model for trap-assisted recombination based on reversible trapping. Finally, we discuss the implications of biexciton blinking for lasing applications.
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Affiliation(s)
- Sander J W Vonk
- Debye Institute for Nanomaterials Science, Utrecht University, Princetonplein 1, 3584 CC Utrecht, The Netherlands
| | - Freddy T Rabouw
- Debye Institute for Nanomaterials Science, Utrecht University, Princetonplein 1, 3584 CC Utrecht, The Netherlands
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20
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Yue L, Li J, Qi Y, Chen J, Wang X, Cao J. Auger Recombination and Carrier-Lattice Thermalization in Semiconductor Quantum Dots under Intense Excitation. NANO LETTERS 2023; 23:2578-2585. [PMID: 36972411 DOI: 10.1021/acs.nanolett.2c04804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
A thorough understanding of the photocarrier relaxation dynamics in semiconductor quantum dots (QDs) is essential to optimize their device performance. However, resolving hot carrier kinetics under high excitation conditions with multiple excitons per dot is challenging because it convolutes several ultrafast processes, including Auger recombination, carrier-phonon scattering, and phonon thermalization. Here, we report a systematic study of the lattice dynamics induced by intense photoexcitation in PbSe QDs. By probing the dynamics from the lattice perspective using ultrafast electron diffraction together with modeling the correlated processes collectively, we can differentiate their roles in photocarrier relaxation. The results reveal that the observed lattice heating time scale is longer than that of carrier intraband relaxation obtained previously using transient optical spectroscopy. Moreover, we find that Auger recombination efficiently annihilates excitons and speeds up lattice heating. This work can be readily extended to other semiconductor QDs systems with varying dot sizes.
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Affiliation(s)
- Luye Yue
- Center for Ultrafast Science and Technology, Key Laboratory for Laser Plasmas (Ministry of Education) and School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Jingjun Li
- Center for Ultrafast Science and Technology, Key Laboratory for Laser Plasmas (Ministry of Education) and School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yingpeng Qi
- Center for Ultrafast Science and Technology, Key Laboratory for Laser Plasmas (Ministry of Education) and School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Jie Chen
- Center for Ultrafast Science and Technology, Key Laboratory for Laser Plasmas (Ministry of Education) and School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xuan Wang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| | - Jianming Cao
- Center for Ultrafast Science and Technology, Key Laboratory for Laser Plasmas (Ministry of Education) and School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
- Physics Department and National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, United States
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21
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Zhang X, Bao H, Chen C, Wu XG, Li M, Ji W, Wang S, Zhong H. The fatigue effects in red emissive CdSe based QLED operated around turn-on voltage. J Chem Phys 2023; 158:131101. [PMID: 37031138 DOI: 10.1063/5.0145471] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023] Open
Abstract
The operational stability is a current bottleneck facing the quantum dot light-emitting diodes (QLEDs). In particular, the device working around turn-on voltage suffers from unbalanced charge injection and heavy power loss. Here, we investigate the operational stability of red emissive CdSe QLEDs operated at different applied voltages. Compared to the rising luminance at higher voltages, the device luminance quickly decreases when loaded around the turn-on voltage, but recovers after unloading or slight heat treatment, which is termed fatigue effects of operational QLED. The electroluminescence and photoluminescence spectra before and after a period of operation at low voltages show that the abrupt decrease in device luminance derives from the reduction of quantum yield in quantum dots. Combined with transient photoluminescence and electroluminescence measurements, as well as equivalent circuit model analysis, the electron accumulation in quantum dots mainly accounts for the observed fatigue effects of a QLED during the operation around turn-on voltage. The underlying mechanisms at the low-voltage working regime will be very helpful for the industrialization of QLED.
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Affiliation(s)
- Xin Zhang
- MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Hui Bao
- MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Cuili Chen
- MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Xian-gang Wu
- MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Menglin Li
- MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Wenyu Ji
- Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, China
| | - Shuangpeng Wang
- Institute of Applied Physics and Materials Engineering, University of Macau, Taipa, Macao SAR, 999078, China
| | - Haizheng Zhong
- MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
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22
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Yumoto G, Kanemitsu Y. Biexciton dynamics in halide perovskite nanocrystals. Phys Chem Chem Phys 2022; 24:22405-22425. [PMID: 36106456 DOI: 10.1039/d2cp02826c] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Lead halide perovskite nanocrystals are attracting considerable interest as next-generation optoelectronic materials. Optical responses of nanocrystals are determined by excitons and exciton complexes such as trions and biexcitons. Understanding of their dynamics is indispensable for the optimal design of optoelectronic devices and the development of new functional properties. Here, we summarize the recent advances on the exciton and biexciton photophysics in lead halide perovskite nanocrystals revealed by femtosecond time-resolved spectroscopy and single-dot spectroscopy. We discuss the impact of the biexciton dynamics on controlling and improving the optical gain.
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Affiliation(s)
- Go Yumoto
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Yoshihiko Kanemitsu
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
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23
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Widness JK, Enny DG, McFarlane-Connelly KS, Miedenbauer MT, Krauss TD, Weix DJ. CdS Quantum Dots as Potent Photoreductants for Organic Chemistry Enabled by Auger Processes. J Am Chem Soc 2022; 144:12229-12246. [PMID: 35772053 DOI: 10.1021/jacs.2c03235] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Strong reducing agents (<-2.0 V vs saturated calomel electrode (SCE)) enable a wide array of useful organic chemistry, but suffer from a variety of limitations. Stoichiometric metallic reductants such as alkali metals and SmI2 are commonly employed for these reactions; however, considerations including expense, ease of use, safety, and waste generation limit the practicality of these methods. Recent approaches utilizing energy from multiple photons or electron-primed photoredox catalysis have accessed reduction potentials equivalent to Li0 and shown how this enables selective transformations of aryl chlorides via aryl radicals. However, in some cases, low stability of catalytic intermediates can limit turnover numbers. Herein, we report the ability of CdS nanocrystal quantum dots (QDs) to function as strong photoreductants and present evidence that a highly reducing electron is generated from two consecutive photoexcitations of CdS QDs with intermediate reductive quenching. Mechanistic experiments suggest that Auger recombination, a photophysical phenomenon known to occur in photoexcited anionic QDs, generates transient thermally excited electrons to enable the observed reductions. Using blue light-emitting diodes (LEDs) and sacrificial amine reductants, aryl chlorides and phosphate esters with reduction potentials up to -3.4 V vs SCE are photoreductively cleaved to afford hydrodefunctionalized or functionalized products. In contrast to small-molecule catalysts, QDs are stable under these conditions and turnover numbers up to 47 500 have been achieved. These conditions can also effect other challenging reductions, such as tosylate protecting group removal from amines, debenzylation of benzyl-protected alcohols, and reductive ring opening of cyclopropane carboxylic acid derivatives.
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Affiliation(s)
- Jonas K Widness
- Department of Chemistry, UW─Madison, Madison, Wisconsin 53706, United States
| | - Daniel G Enny
- Department of Chemistry, UW─Madison, Madison, Wisconsin 53706, United States
| | | | - Mahilet T Miedenbauer
- Materials Science Program, University of Rochester, Rochester, New York 14627, United States
| | - Todd D Krauss
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States.,Materials Science Program, University of Rochester, Rochester, New York 14627, United States.,Institute of Optics, University of Rochester, Rochester, New York 14627, United States
| | - Daniel J Weix
- Department of Chemistry, UW─Madison, Madison, Wisconsin 53706, United States
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24
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Paul S, Samanta A. Phase-Stable and Highly Luminescent CsPbI 3 Perovskite Nanocrystals with Suppressed Photoluminescence Blinking. J Phys Chem Lett 2022; 13:5742-5750. [PMID: 35713649 DOI: 10.1021/acs.jpclett.2c01463] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Despite their low band gap, the utility of CsPbI3 nanocrystals (NCs) in solar photovoltaic and optoelectronic applications is rather limited because of their phase instability and photoluminescence (PL) intermittency. Herein we show that phase-pure, monodispersed, stable and highly luminescent CsPbI3 NCs can be obtained by tweaking the conventional hot-injection method employing NH4I as an additional precursor. Single-particle studies show a significant suppression of PL blinking. Among all NCs studied, 60% exhibit only high-intensity ON states with a narrow distribution of intensity. The remaining 40% of NCs exhibit a much wider distribution of PL intensity with a significant contribution of low-intensity OFF states. Excellent characteristics of these CsPbI3 NCs are shown to be the result of NH4+ replacing some surface Cs+ of an iodide-rich surface of the NCs. These phase-stable and highly luminescent CsPbI3 NCs with significantly suppressed PL blinking can be useful single-photon emitters and promising materials for optoelectronic and solar photovoltaic applications.
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Affiliation(s)
- Sumanta Paul
- School of Chemistry, University of Hyderabad, Hyderabad 500046, India
| | - Anunay Samanta
- School of Chemistry, University of Hyderabad, Hyderabad 500046, India
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25
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Ballabio M, Cánovas E. Electron Transfer at Quantum Dot–Metal Oxide Interfaces for Solar Energy Conversion. ACS NANOSCIENCE AU 2022; 2:367-395. [PMID: 36281255 PMCID: PMC9585894 DOI: 10.1021/acsnanoscienceau.2c00015] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Electron transfer
at a donor–acceptor quantum dot–metal
oxide interface is a process fundamentally relevant to solar energy
conversion architectures as, e.g., sensitized solar cells and solar
fuels schemes. As kinetic competition at these technologically relevant
interfaces largely determines device performance, this Review surveys
several aspects linking electron transfer dynamics and device efficiency;
this correlation is done for systems aiming for efficiencies up to
and above the ∼33% efficiency limit set by Shockley and Queisser
for single gap devices. Furthermore, we critically comment on common
pitfalls associated with the interpretation of kinetic data obtained
from current methodologies and experimental approaches, and finally,
we highlight works that, to our judgment, have contributed to a better
understanding of the fundamentals governing electron transfer at quantum
dot–metal oxide interfaces.
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Affiliation(s)
- Marco Ballabio
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA Nanociencia), 28049 Madrid, Spain
| | - Enrique Cánovas
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA Nanociencia), 28049 Madrid, Spain
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26
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Ghosh S, Hollingsworth JA, Gallea JI, Majumder S, Enderlein J, Chizhik AI. Excited state lifetime modulation in semiconductor nanocrystals for super-resolution imaging. NANOTECHNOLOGY 2022; 33:365201. [PMID: 35617874 DOI: 10.1088/1361-6528/ac73a2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 05/26/2022] [Indexed: 06/15/2023]
Abstract
We report on proof of principle measurements of a concept for a super-resolution imaging method that is based on excitation field density-dependent lifetime modulation of semiconductor nanocrystals. The prerequisite of the technique is access to semiconductor nanocrystals with emission lifetimes that depend on the excitation intensity. Experimentally, the method requires a confocal microscope with fluorescence-lifetime measurement capability that makes it easily accessible to a broad optical imaging community. We demonstrate with single particle imaging that the method allows one to achieve a spatial resolution of the order of several tens of nanometers at moderate fluorescence excitation intensity.
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Affiliation(s)
- Subhabrata Ghosh
- Third Institute of Physics-Biophysics, University of Göttingen, Friedrich-Hund-Platz 1, D-37077 Göttingen, Germany
| | - Jennifer A Hollingsworth
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM 87545, United States of America
| | - Jose Ignacio Gallea
- Third Institute of Physics-Biophysics, University of Göttingen, Friedrich-Hund-Platz 1, D-37077 Göttingen, Germany
| | - Somak Majumder
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM 87545, United States of America
| | - Jörg Enderlein
- Third Institute of Physics-Biophysics, University of Göttingen, Friedrich-Hund-Platz 1, D-37077 Göttingen, Germany
- Cluster of Excellence 'Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells' (MBExC), Georg August University, D-37077 Göttingen, Germany
| | - Alexey I Chizhik
- Third Institute of Physics-Biophysics, University of Göttingen, Friedrich-Hund-Platz 1, D-37077 Göttingen, Germany
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27
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Chae WS, Cho S, Jung JY, Kim JH, Lee JS. Multiple-Route Exciton Recombination Dynamics and Improved Stability of Perovskite Quantum Dots by Plasmonic Photonic Crystal. J Phys Chem Lett 2022; 13:5040-5048. [PMID: 35652905 DOI: 10.1021/acs.jpclett.2c00735] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
We have studied the excited-state exciton recombination dynamics of perovskite quantum dots (QDs) through time-resolved photoluminescence (PL), PL blinking, PL intensity-dependent lifetime modulation, and long-term photostability tests. The various spectroscopic characterizations elucidate that the perovskite QDs have multiple intrinsic exciton recombination routes even in a single QD, i.e., exciton, biexciton, and positive/negative trions, which are dissimilarly contributed to ON and OFF state emissions. We also find that the enhanced radiative recombination from placing green QDs on a photonic Ag nanotip array induces notably improved long-term PL stability. We consider that the accelerated radiative recombination of QDs by strong coupling with the plasmonics of the photonic Ag nanotip array, while eliminating nonradiative pathways, is proven to be a critical factor for improved long-term stability.
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Affiliation(s)
- Weon-Sik Chae
- Daegu Center, Korea Basic Science Institute, Daegu 41566, Republic of Korea
| | - Sinyoung Cho
- Department of Energy Science and Engineering, DGIST, Daegu 42988, Republic of Korea
| | - Joo-Yun Jung
- Nano-convergence Mechanical Systems Research Division, Korea Institute of Machinery and Materials, Daejeon 305-343, Republic of Korea
| | - Jong-Hwa Kim
- Daegu Center, Korea Basic Science Institute, Daegu 41566, Republic of Korea
| | - Jong-Soo Lee
- Department of Energy Science and Engineering, DGIST, Daegu 42988, Republic of Korea
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28
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Tang Y, Qin Q, Yang H, Feng S, Zhang C, Zhang J, Xiao M, Wang X. Electrical control of biexciton Auger recombination in single CdSe/CdS nanocrystals. NANOSCALE 2022; 14:7674-7681. [PMID: 35548946 DOI: 10.1039/d2nr00305h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The Auger recombination effect is strongly enhanced in semiconductor nanocrystals due to the quantum confinement, and various strategies in chemical synthesis have been employed so far to suppress this nonradiative decay pathway of multiple excitons. Here we apply external electric fields on single CdSe/CdS giant nanocrystals at room temperature, showing that the biexciton Auger and single-exciton radiative rates can be averagely decreased by ∼40 and ∼10%, respectively. In addition to a reduced overlap of the electron-hole wavefunctions, the large decrease of biexciton Auger rate could be contributed by the enhanced exciton-exciton repulsion, while the electron-hole exchange interaction might be weakened to cause the relatively small decrease of the single-exciton radiative rate. The above findings have thus proved that the external electric field can serve as a post-synthetic knob to tune the exciton recombination dynamics in semiconductor nanocrystals towards their efficient applications in various optoelectronic devices.
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Affiliation(s)
- Ying Tang
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
| | - Qilin Qin
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
| | - Hongyu Yang
- Advanced Photonics Center, School of Electronic Science and Engineering, Southeast University, Nanjing 210096, China.
| | - Shengnan Feng
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
| | - Chunfeng Zhang
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
| | - Jiayu Zhang
- Advanced Photonics Center, School of Electronic Science and Engineering, Southeast University, Nanjing 210096, China.
| | - Min Xiao
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
- Department of Physics, University of Arkansas, Fayetteville, Arkansas 72701, USA
| | - Xiaoyong Wang
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
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29
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Yang H, Li S, Zhang L, Xiang W, Zhang Y, Wang X, Xiao M, Cui Y, Zhang J. Observation of high-density multi-excitons in medium-size CdSe/CdZnS/ZnS colloidal quantum dots through transient spectroscopy and their optical gain properties. NANOSCALE 2022; 14:5369-5376. [PMID: 35311884 DOI: 10.1039/d2nr00761d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Semiconductor quantum dots have extremely significant advantages in terms of optoelectronic devices. However, it is unfeasible to avoid the generation of charged exciton states during operation. Such states can change the radiation recombination rate and bring additional non-radiative Auger recombination channels. Herein, we synthesize high photoluminescence quantum yield medium-size CdSe/CdZnS/ZnS core/alloy shell/shell QDs. Their multiexciton spectra and dynamics were systematically studied by pump-power-dependent fluorescence blinking and time-correlated spectroscopy. The lifetimes of positively/negatively charged trions and biexcitons are estimated to be 0.74/6.1 and 0.16 ns, respectively. It demonstrated that the band-edge biexciton is influenced by the Coulomb interaction and Stark effect. The amplified spontaneous emission threshold is only 81 μJ cm-2 and can retain a long operation lifetime under continuous pumping. A vertical microcavity surface-emitting laser device is fabricated using these QDs. The coupling factor between the spontaneous emission and cavity mode is 0.81, which benefits the low stimulated emission threshold. This work provides a new perspective of the charged states in the multiexciton AR process in the QDs, implying a promising application prospect of such QDs as optical gain materials in "zero-threshold" laser fabrication.
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Affiliation(s)
- Hongyu Yang
- Advanced Photonic Center, School of Electronic science and Engineering, Southeast University, Nanjing 210096, China.
| | - Si Li
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, and School of Physics, Nanjing University, Nanjing 210093, China.
| | - Lei Zhang
- Advanced Photonic Center, School of Electronic science and Engineering, Southeast University, Nanjing 210096, China.
| | - Wenbin Xiang
- Advanced Photonic Center, School of Electronic science and Engineering, Southeast University, Nanjing 210096, China.
| | - Yi Zhang
- College of Energy and Electrical Engineering, Hohai University, Nanjing, 210098, China.
| | - Xiaoyong Wang
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, and School of Physics, Nanjing University, Nanjing 210093, China.
| | - Min Xiao
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, and School of Physics, Nanjing University, Nanjing 210093, China.
- University of Arkansas, Fayetteville, Arkansas 72701, USA
| | - Yiping Cui
- Advanced Photonic Center, School of Electronic science and Engineering, Southeast University, Nanjing 210096, China.
| | - Jiayu Zhang
- Advanced Photonic Center, School of Electronic science and Engineering, Southeast University, Nanjing 210096, China.
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30
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Yu P, Yuan Q, Zhao J, Zhang H, Ji W. Electronic and Excitonic Processes in Quantum Dot Light-Emitting Diodes. J Phys Chem Lett 2022; 13:2878-2884. [PMID: 35333050 DOI: 10.1021/acs.jpclett.2c00604] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
A modified Langevin model has been proposed to study the electronic and excitonic dynamic processes in quantum dot light-emitting diodes (QLEDs), and the electroluminescence onset processes of the QLEDs under different charge-injection conditions have been explored. The simulation results are in good agreement with experimental curves, confirming the feasibility of this model. It is demonstrated that the formation of an exciton on the quantum dots (QDs) with one electron injected first followed by one hole is much more effective than that with the reverse sequence. That is, charging a QD with one electron first is more favorable for device performance enhancement, which is attributed to the low (high) Auger recombination rate of negative (positive) trions of commonly used type I QDs. Additionally, we demonstrate that enough electron injection is one of the prerequisites for high-performance QLEDs based on these type I QDs.
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Affiliation(s)
- Panlong Yu
- Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), Department of Physics, Jilin University, Changchun, Jilin 130023, People's Republic of China
| | - Qilin Yuan
- Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), Department of Physics, Jilin University, Changchun, Jilin 130023, People's Republic of China
| | - Jialong Zhao
- Center on Nanoenergy Research, School of Physical Science and Technology, Guangxi University, Nanning, Guangxi 530004, People's Republic of China
| | - Hanzhuang Zhang
- Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), Department of Physics, Jilin University, Changchun, Jilin 130023, People's Republic of China
| | - Wenyu Ji
- Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), Department of Physics, Jilin University, Changchun, Jilin 130023, People's Republic of China
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31
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Lee Y, Jo DY, Kim T, Jo JH, Park J, Yang H, Kim D. Effectual Interface and Defect Engineering for Auger Recombination Suppression in Bright InP/ZnSeS/ZnS Quantum Dots. ACS APPLIED MATERIALS & INTERFACES 2022; 14:12479-12487. [PMID: 35238532 DOI: 10.1021/acsami.1c20088] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The main issue in developing a quantum dot light-emitting diode (QLED) display lies in successfully replacing heavy metals with environmentally benign materials while maintaining high-quality device performance. Nonradiative Auger recombination is one of the major limiting factors of QLED performance and should ideally be suppressed. This study scrutinizes the effects of the shell structure and composition on photoluminescence (PL) properties of InP/ZnSeS/ZnS quantum dots (QDs) through ensemble and single-dot spectroscopic analyses. Employing gradient shells is discovered to suppress Auger recombination to a high degree, allowing charged QDs to be luminescent comparatively with neutral QDs. The "lifetime blinking" phenomenon is observed as evidence of suppressed Auger recombination. Furthermore, single-QD measurements reveal that gradient shells in QDs reduce spectral diffusion and elevate the energy barrier for charge trapping. Shell composition dependency in the gradience effect is observed. An increase in the ZnS composition (ZnS >50%) in the gradient shell introduces lattice mismatch between the core and the shell and therefore rather reverses the effect and reduces the QD performance.
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Affiliation(s)
- YuJin Lee
- Department of Chemistry, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Dae-Yeon Jo
- Department of Materials Science and Engineering, Hongik University, 94 Wausan-ro, Mapo-gu, Seoul 04066, Republic of Korea
| | - Taehee Kim
- Department of Chemistry, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Jung-Ho Jo
- Department of Materials Science and Engineering, Hongik University, 94 Wausan-ro, Mapo-gu, Seoul 04066, Republic of Korea
| | - Jumi Park
- Department of Chemistry, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Heesun Yang
- Department of Materials Science and Engineering, Hongik University, 94 Wausan-ro, Mapo-gu, Seoul 04066, Republic of Korea
| | - Dongho Kim
- Department of Chemistry, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
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32
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Trinh PT, Hasenstab S, Braun M, Wachtveitl J. Ultrafast separation of multiexcitons within core/shell quantum dot hybrid systems. NANOSCALE 2022; 14:3561-3567. [PMID: 35230365 DOI: 10.1039/d1nr07710d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
We investigated the electron transfer processes in methylene blue-CdTe and methylene blue-CdTe/CdSe complexes by steady state and femtosecond transient absorption spectroscopy by selective excitation of the quantum dot (QD) moiety. The ultrafast electron transfer is accelerated by the shell growth due to the separation of the charge carriers and the resulting increase of electron density in the shell. Transmission electron microscope images show that the successive addition of shell material deforms the spherical QDs until they adopt a tetrapodal shape. The increased donor-acceptor distance in the tetrapodal CdTe/CdSe QDs leads to a slower electron transfer. Photon flux dependent transient absorption measurements indicate the separation of two electrons for the QDs with a thin shell and thus demonstrate that charge carrier multiplication can be directly utilized for increased charge transfer in this type of QD hybrid system.
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Affiliation(s)
- Phuong Thao Trinh
- Institute of Physical and Theoretical Chemistry, Goethe-University Frankfurt, Max-von-Laue-Str. 7, D-60438 Frankfurt am Main, Germany.
| | - Sina Hasenstab
- Institute of Physical and Theoretical Chemistry, Goethe-University Frankfurt, Max-von-Laue-Str. 7, D-60438 Frankfurt am Main, Germany.
| | - Markus Braun
- Institute of Physical and Theoretical Chemistry, Goethe-University Frankfurt, Max-von-Laue-Str. 7, D-60438 Frankfurt am Main, Germany.
| | - Josef Wachtveitl
- Institute of Physical and Theoretical Chemistry, Goethe-University Frankfurt, Max-von-Laue-Str. 7, D-60438 Frankfurt am Main, Germany.
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33
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Shi J, Sun W, Utzat H, Farahvash A, Gao FY, Zhang Z, Barotov U, Willard AP, Nelson KA, Bawendi MG. All-optical fluorescence blinking control in quantum dots with ultrafast mid-infrared pulses. NATURE NANOTECHNOLOGY 2021; 16:1355-1361. [PMID: 34811550 DOI: 10.1038/s41565-021-01016-w] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 09/22/2021] [Indexed: 06/13/2023]
Abstract
Photoluminescence intermittency is a ubiquitous phenomenon, reducing the temporal emission intensity stability of single colloidal quantum dots (QDs) and the emission quantum yield of their ensembles. Despite efforts to achieve blinking reduction by chemical engineering of the QD architecture and its environment, blinking still poses barriers to the application of QDs, particularly in single-particle tracking in biology or in single-photon sources. Here, we demonstrate a deterministic all-optical suppression of QD blinking using a compound technique of visible and mid-infrared excitation. We show that moderate-field ultrafast mid-infrared pulses (5.5 μm, 150 fs) can switch the emission from a charged, low quantum yield grey trion state to the bright exciton state in CdSe/CdS core-shell QDs, resulting in a significant reduction of the QD intensity flicker. Quantum-tunnelling simulations suggest that the mid-infrared fields remove the excess charge from trions with reduced emission quantum yield to restore higher brightness exciton emission. Our approach can be integrated with existing single-particle tracking or super-resolution microscopy techniques without any modification to the sample and translates to other emitters presenting charging-induced photoluminescence intermittencies, such as single-photon emissive defects in diamond and two-dimensional materials.
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Affiliation(s)
- Jiaojian Shi
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Weiwei Sun
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Hendrik Utzat
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA
| | - Ardavan Farahvash
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Frank Y Gao
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Zhuquan Zhang
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Ulugbek Barotov
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Adam P Willard
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Keith A Nelson
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA.
| | - Moungi G Bawendi
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA.
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Hu Z, Shu Y, Qin H, Hu X, Peng X. Water Effects on Colloidal Semiconductor Nanocrystals: Correlation of Photophysics and Photochemistry. J Am Chem Soc 2021; 143:18721-18732. [PMID: 34705444 DOI: 10.1021/jacs.1c09363] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
With high-quality CdSe/CdS core/shell nanocrystals as the main model system and under a controlled atmosphere, responses of photoexcited semiconductor nanocrystals to two active species (water and/or oxygen) in an ambient environment are studied systematically. Under photoexcitation, although high-quality semiconductor nanocrystals in either thin solid films or various solutions have a near-unity photoluminescence quantum yield, there is still a small probability (∼10-5 per photon absorbed) to be photoreduced by the water molecules efficiently accumulated in the highly hydrophilic nanocrystal-ligands interface. The resulting negatively charged nanocrystals are the starting point of most photophysical variations, and the hydroxyl radical─key photo-oxidation product of water─plays the main role for initiating various photochemical processes. Depending on the supplementation of water to the interface, accessibility to oxygen, photoirradiation power, type of matrices, type of measurement schemes, and solubility of nanocrystals in the solution, various photophysical/photochemical phenomena─either reported or not reported in the literature─are reproducibly observed. Results confirm that photophysical properties and photochemical reactions can be well-correlated, offering a unified and unique basis for fundamental studies and the design of processing techniques in industry.
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Affiliation(s)
- Zhuang Hu
- Key Laboratory of Excited-State Materials of Zhejiang Province and Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Yufei Shu
- Key Laboratory of Excited-State Materials of Zhejiang Province and Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Haiyan Qin
- Key Laboratory of Excited-State Materials of Zhejiang Province and Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Xiaofei Hu
- Key Laboratory of Excited-State Materials of Zhejiang Province and Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Xiaogang Peng
- Key Laboratory of Excited-State Materials of Zhejiang Province and Department of Chemistry, Zhejiang University, Hangzhou 310027, China
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35
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So WY, Abbas S, Li Q, Jin R, Peteanu LA. Single and bi-excitonic characteristics of ligand-modified silicon nanoparticles as demonstrated via single particle photon statistics and plasmonic effects. NANOSCALE 2021; 13:15238-15247. [PMID: 34105572 DOI: 10.1039/d1nr00108f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Silicon nanoparticles (Si NPs) are of great interest to researchers due to their fluorescence properties, low toxicity, and the low cost of the Si precursor. Recent studies have shown that Si NPs surface-modified with secondary aryl amine ligands emit light at wavelengths ranging from cyan to yellow and with quantum yields of up to 90%. The predominant emitting state in these species has been assigned to a charge-transfer (CT) transition from the ligand to the Si particle as the emission wavelength is determined by the dipolar properties of the ligand rather than the size of the Si core. This contribution focuses on the single-molecule emission properties of Si NPs functionalized with a 1,2,3,4-tetrahydrocarbazole-4-one ligand (Te-On) which have a peak emission wavelength of 550 nm and a quantum yield of 90%. In single-particle dispersed emission spectra, a weak long-wavelength sideband is seen in addition to the dominant yellow emission derived from the CT state. The photon statistical behavior of single Si NPs in the red emission region is consistent with that of a state having collective or bi-excitonic character. In contrast, the yellow emission exhibits predominantly CT character. Deposition of the sample onto a thin gold film causes the CT emission to be quenched whereas that attributed to a bi-exciton state of the Si core is enhanced. These results provide new insights into the mechanism of single-molecule intensity fluctuation in these surface-modified silicon nanoparticles that will benefit proposed applications in biological labeling and as single-photon sources.
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Affiliation(s)
- Woong Young So
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA, 15213, USA.
| | - Sikandar Abbas
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA, 15213, USA.
| | - Qi Li
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA, 15213, USA.
| | - Rongchao Jin
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA, 15213, USA.
| | - Linda A Peteanu
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA, 15213, USA.
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36
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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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37
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Cheng Y, Wan H, Liang T, Liu C, Wu M, Hong H, Liu K, Shen H. Continuously Graded Quantum Dots: Synthesis, Applications in Quantum Dot Light-Emitting Diodes, and Perspectives. J Phys Chem Lett 2021; 12:5967-5978. [PMID: 34160222 DOI: 10.1021/acs.jpclett.1c01554] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Colloidal quantum dot (QD) light-emitting diodes (QLEDs) hold the promise of next-generation displays and illumination owing to their excellent color saturation, high efficiency, and solution processability. For achieving high-performance light-emitting diodes (LEDs), engineering the fine compositions and structures of QDs is of paramount importance and attracts tremendous research interest. The recently developed continuously graded QDs (cg-QDs) with gradually altered nanocompositions and electronic band structures present the most advanced example in this area. In this Perspective, we summarize the current progress in LEDs based on cg-QDs, mainly concentrating on their synthesis and advantages in addressing the great challenges in QLEDs, like efficiency roll-off at high current densities, short operation lifetimes at high brightness, and low brightness near the voltage around the bandgap. In addition, we propose accessible approaches exploiting the cutting-edge mechanisms and techniques to further optimize and improve the performance of QLEDs.
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Affiliation(s)
- Yang Cheng
- State Key Laboratory for Mesoscopic Physics, Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
- Key Laboratory for Special Functional Materials, Ministry of Education, School of Materials Science and Engineering, Henan University, Kaifeng 475004, China
| | - Haoyue Wan
- State Key Laboratory for Mesoscopic Physics, Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
| | - Tianyu Liang
- State Key Laboratory for Mesoscopic Physics, Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
| | - Can Liu
- State Key Laboratory for Mesoscopic Physics, Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
| | - Muhong Wu
- International Center for Quantum Materials, Collaborative Innovation Center of Quantum Matter, Peking University, Beijing 100871, China
- Songshan Lake Laboratory for Materials Science, Dongguan 523808, China
- Interdisciplinary Institute of Light-Element Quantum Materials and Research Center for Light-Element Advanced Materials, Peking University, Beijing 100871, China
| | - Hao Hong
- State Key Laboratory for Mesoscopic Physics, Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
| | - Kaihui Liu
- State Key Laboratory for Mesoscopic Physics, Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
- International Center for Quantum Materials, Collaborative Innovation Center of Quantum Matter, Peking University, Beijing 100871, China
| | - Huaibin Shen
- Key Laboratory for Special Functional Materials, Ministry of Education, School of Materials Science and Engineering, Henan University, Kaifeng 475004, China
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38
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Das A, Mishra K, Ghosh S. Revealing Explicit Microsecond Carrier Diffusion from One Emission Center to Another in an All-Inorganic Perovskite Nanocrystal. J Phys Chem Lett 2021; 12:5413-5422. [PMID: 34080871 DOI: 10.1021/acs.jpclett.1c01154] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Blinking of freely diffusing CsPbBr3 nanocrystals (NCs) is studied using fluorescence lifetime correlation spectroscopy (FLCS). Emitted photons from each NCs are assigned to an emission state (exciton or trap) based on their lifetime. Subsequently, an intrastate autocorrelation function (ACF) and an interstate cross-correlation function (CCF) are constructed. Fitting of the AFCs with an analytical model shows that, at low excitation power, the microsecond blinking timescale of the exciton state matches well with that of the trap state. Most interestingly, both of those timescales further correlate with the microsecond growth timescale of the CCF. The strong anti-correlation of the CCF along with the stretched exponential nature of the blinking kinetics confirms the involvement of carrier diffusion and dispersive trap states in NC blinking. At high excitation power, enhanced sample heterogeneity causes a more dispersive blinking. To the best of our knowledge, this is the first report of a NC blinking study using a single-molecule-based FLCS technique.
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Affiliation(s)
- Ayendrila Das
- School of Chemical Sciences, National Institute of Science Education and Research, Homi Bhabha National Institute (HBNI), Khurda 752050, Odisha, India
| | - Krishna Mishra
- School of Chemical Sciences, National Institute of Science Education and Research, Homi Bhabha National Institute (HBNI), Khurda 752050, Odisha, India
| | - Subhadip Ghosh
- School of Chemical Sciences, National Institute of Science Education and Research, Homi Bhabha National Institute (HBNI), Khurda 752050, Odisha, India
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Hou X, Qin H, Peng X. Enhancing Dielectric Screening for Auger Suppression in CdSe/CdS Quantum Dots by Epitaxial Growth of ZnS Shell. NANO LETTERS 2021; 21:3871-3878. [PMID: 33938759 DOI: 10.1021/acs.nanolett.1c00396] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Auger recombination is the main nonradiative process in multicarrier states of high-quality quantum dots (QDs). For the most-studied CdSe/CdS core/shell QDs, we effectively reduce the biexciton Auger rate by enhancing dielectric screening of band-edge carriers via epitaxial growth of additional ZnS shells. Super volume scaling of negative-trion Auger lifetime for CdSe/CdS core/shell QDs is achieved with the outermost ZnS shells. The volume of CdSe/CdS/ZnS QDs can be less than half that of CdSe/CdS QDs with the same negative-trion Auger lifetime. Auger suppression by the ZnS shells is more pronounced for QDs with wave functions of band-edge carriers spreading close to the inorganic-organic interface, such as CdSe/CdS QDs with small cores. A maximum drop of biexciton Auger rate of ∼50% and a maximum enhancement of biexciton emission quantum yield of 75% are achieved. Auger engineering by dielectric screening opens up new opportunities to improve the emission properties of multicarrier states in QDs.
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Affiliation(s)
- Xiaoqi Hou
- Key Laboratory of Excited-State Materials of Zhejiang Province, and Department of Chemistry, Zhejiang University, Hangzhou, 310027, P. R. China
- Key Laboratory of Intelligent Sensing Materials and Chip Integration Technology of Zhejiang Province, Hangzhou Innovation Institute, Beihang University, Hangzhou, 310051, P.R. China
| | - Haiyan Qin
- Key Laboratory of Excited-State Materials of Zhejiang Province, and Department of Chemistry, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Xiaogang Peng
- Key Laboratory of Excited-State Materials of Zhejiang Province, and Department of Chemistry, Zhejiang University, Hangzhou, 310027, P. R. China
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Revealing the Exciton Fine Structure in Lead Halide Perovskite Nanocrystals. NANOMATERIALS 2021; 11:nano11041058. [PMID: 33924196 PMCID: PMC8074593 DOI: 10.3390/nano11041058] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 04/14/2021] [Accepted: 04/16/2021] [Indexed: 12/25/2022]
Abstract
Lead-halide perovskite nanocrystals (NCs) are attractive nano-building blocks for photovoltaics and optoelectronic devices as well as quantum light sources. Such developments require a better knowledge of the fundamental electronic and optical properties of the band-edge exciton, whose fine structure has long been debated. In this review, we give an overview of recent magneto-optical spectroscopic studies revealing the entire excitonic fine structure and relaxation mechanisms in these materials, using a single-NC approach to get rid of their inhomogeneities in morphology and crystal structure. We highlight the prominent role of the electron-hole exchange interaction in the order and splitting of the bright triplet and dark singlet exciton sublevels and discuss the effects of size, shape anisotropy and dielectric screening on the fine structure. The spectral and temporal manifestations of thermal mixing between bright and dark excitons allows extracting the specific nature and strength of the exciton–phonon coupling, which provides an explanation for their remarkably bright photoluminescence at low temperature although the ground exciton state is optically inactive. We also decipher the spectroscopic characteristics of other charge complexes whose recombination contributes to photoluminescence. With the rich knowledge gained from these experiments, we provide some perspectives on perovskite NCs as quantum light sources.
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41
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Kim T, Won YH, Jang E, Kim D. Negative Trion Auger Recombination in Highly Luminescent InP/ZnSe/ZnS Quantum Dots. NANO LETTERS 2021; 21:2111-2116. [PMID: 33635669 DOI: 10.1021/acs.nanolett.0c04740] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Upon demonstrating self-luminescing quantum dot based light-emitting devices (QD-LEDs), rapid Auger recombination acts as one of the performance limiting factors. Here, we report the Auger processes of highly luminescent InP/ZnSe/ZnS QDs with different midshell structures that affect the performances of QD-LEDs. Transient PL measurements reveal that exciton-exciton binding energy is dependent on the midshell thickness, which implies that the intercarrier Coulomb interaction caused by the introduction of excess charges may come under the influence of midshell thickness which is in contrast with the nearly stationary single exciton behavior. Photochemical electron-doping and optical measurements of a single QD show that negative trion Auger recombination exhibits strong correlation with midshell thickness, which is supported by the dynamics of a hot electron generated in the midshell. These results highlight the role of excess electrons and the effects of engineered shell structures in InP/ZnSe/ZnS QDs, which eventually determine the Auger recombination and QD-LED performances.
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Affiliation(s)
- Taehee Kim
- Department of Chemistry, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Yu-Ho Won
- Samsung Advanced Institute of Technology, Samsung Electronics, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 16678, Republic of Korea
| | - Eunjoo Jang
- Samsung Advanced Institute of Technology, Samsung Electronics, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 16678, Republic of Korea
| | - Dongho Kim
- Department of Chemistry, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
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Abstract
![]()
Electronic
coupling and hence hybridization of atoms serves as
the basis for the rich properties for the endless library of naturally
occurring molecules. Colloidal quantum dots (CQDs) manifesting quantum
strong confinement possess atomic-like characteristics with s and p electronic levels, which popularized
the notion of CQDs as artificial atoms. Continuing this analogy, when
two atoms are close enough to form a molecule so that their orbitals
start overlapping, the orbitals energies start to split into bonding
and antibonding states made out of hybridized orbitals. The same concept
is also applicable for two fused core–shell nanocrystals in
close proximity. Their band edge states, which dictate the emitted
photon energy, start to hybridize, changing their electronic and optical
properties. Thus, an exciting direction of “artificial molecules”
emerges, leading to a multitude of possibilities for creating a library
of new hybrid nanostructures with novel optoelectronic properties
with relevance toward diverse applications including quantum technologies. The controlled separation and the barrier height between two adjacent
quantum dots are key variables for dictating the magnitude of the
coupling energy of the confined wave functions. In the past, coupled
double quantum dot architectures prepared by molecular beam epitaxy
revealed a coupling energy of few millielectron volts, which limits
the applications to mostly cryogenic operation. The realization of
artificial quantum molecules with sufficient coupling energy detectable
at room temperature calls for the use of colloidal semiconductor nanocrystal
building blocks. Moreover, the tunable surface chemistry widely opens
the predesigned attachment strategies as well as the solution processing
ability of the prepared artificial molecules, making the colloidal
nanocrystals as an ideal candidate for this purpose. Despite several
approaches that demonstrated enabling of the coupled structures, a
general and reproducible method applicable to a broad range of colloidal
quantum materials is needed for systematic tailoring of the coupling
strength based on a dictated barrier This Account addresses
the development of nanocrystal chemistry to create
coupled colloidal quantum dot molecules and to study the
controlled electronic coupling and their emergent properties. The
simplest nanocrystal molecule, a homodimer formed from two core/shell
nanocrystal monomers, in analogy to homonuclear diatomic molecules,
serves as a model system. The shell material of the two CQDs is structurally
fused, resulting in a continuous crystal. This lowers the potential
energy barrier, enabling the hybridization of the electronic wave
functions. The direct manifestation of the hybridization reflects
on the band edge transition shifting toward lower energy and is clearly
resolved at room temperature. The hybridization energy within the
single homodimer molecule is strongly correlated with the extent of
structural continuity, the delocalization of the exciton wave function,
and the barrier thickness as calculated numerically. The hybridization
impacts the emitted photon statistics manifesting faster radiative
decay rate, photon bunching effect, and modified Auger recombination
pathway compared to the monomer artificial atoms. Future perspectives
for the nanocrystals chemistry paradigm are also highlighted.
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Affiliation(s)
- Somnath Koley
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
- The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Jiabin Cui
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
- The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Yossef E. Panfil
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
- The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Uri Banin
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
- The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
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43
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Guo W, Tang J, Zhang G, Li B, Yang C, Chen R, Qin C, Hu J, Zhong H, Xiao L, Jia S. Photoluminescence Blinking and Biexciton Auger Recombination in Single Colloidal Quantum Dots with Sharp and Smooth Core/Shell Interfaces. J Phys Chem Lett 2021; 12:405-412. [PMID: 33356280 DOI: 10.1021/acs.jpclett.0c03065] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
There is an inconsistence on whether a smooth core/shell interface can reduce Auger recombination and suppress photoluminescence (PL) blinking in single colloidal quantum dots (QDs). Here, we investigate the influence of a core/shell interface on PL blinking and biexciton Auger recombination by comparing the single-dot PL spectra of CdxZn1-xSeyS1-y/ZnS core/shell QDs with sharp and smooth interfaces. The inconsistence can be clarified when considering different PL blinking mechanisms. For the single QDs showing Auger blinking, a smooth core/shell interface potential can suppress PL blinking through reducing the Auger recombination. In contrast, we find slightly reduced biexciton Auger recombination rates but increased PL blinking activities in the band-edge carrier (BC)-blinking QDs with the smooth core/shell interface. This is because the smooth interface potential cannot reduce the PL blinking caused by the transfer of electrons to the surface states; however, there is potential to increase electron wave function delocalization for reducing the biexciton Auger recombination rate.
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Affiliation(s)
- Wenli Guo
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Jialun Tang
- Beijing Key Laboratory of Nanophotonics and Ultrafine Optoelectronic Systems, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Guofeng Zhang
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Bin Li
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
- Key Laboratory of Spectral Measurement and Analysis of Shanxi Province, College of Physics and Information Engineering, Shanxi Normal University, Linfen 041004, China
| | - Changgang Yang
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Ruiyun Chen
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Chengbing Qin
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Jianyong Hu
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Haizheng Zhong
- Beijing Key Laboratory of Nanophotonics and Ultrafine Optoelectronic Systems, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Liantuan Xiao
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Suotang Jia
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
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44
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Mukherjee A, Dutta P, Bhattacharyya B, Rajasekar GP, Simlandy AK, Pandey A. Ultrafast spectroscopic investigation of the artificial photosynthetic activity of CuAlS
2
/ZnS quantum dots. NANO SELECT 2021. [DOI: 10.1002/nano.202000219] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
- Arpita Mukherjee
- Indian Institute of Science Solid State and Structural Chemistry Unit Bangalore 560012 India
| | - Pranab Dutta
- Indian Institute of Science Solid State and Structural Chemistry Unit Bangalore 560012 India
| | - Biswajit Bhattacharyya
- Indian Institute of Science Solid State and Structural Chemistry Unit Bangalore 560012 India
| | - Guru Pratheep Rajasekar
- Indian Institute of Science Solid State and Structural Chemistry Unit Bangalore 560012 India
| | - Amit Kumar Simlandy
- Department of Organic Chemistry Indian Institute of Science Bangalore 560012 India
| | - Anshu Pandey
- Indian Institute of Science Solid State and Structural Chemistry Unit Bangalore 560012 India
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45
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Affiliation(s)
- Christopher Melnychuk
- James Franck Institute, The University of Chicago, Chicago, Illinois 60637, United States
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46
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Li B, Zhang G, Zhang Y, Yang C, Guo W, Peng Y, Chen R, Qin C, Gao Y, Hu J, Wu R, Ma J, Zhong H, Zheng Y, Xiao L, Jia S. Biexciton Dynamics in Single Colloidal CdSe Quantum Dots. J Phys Chem Lett 2020; 11:10425-10432. [PMID: 33269933 DOI: 10.1021/acs.jpclett.0c02832] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The investigation of biexciton dynamics in single colloidal quantum dots (QDs) is critical to biexciton-based applications. Generally, a biexciton exhibits an extremely low photoluminescence (PL) quantum yield as well as very fast PL decay due to strong nonradiative Auger recombination, making it difficult to investigate the biexciton dynamics. Here, we develop a quantitative method based on intensity- and time-resolved photon statistics to investigate the biexciton dynamics in single colloidal QDs. This robust method can be used under high-excitation conditions to determine the absolute radiative and Auger recombination rates of both neutral and charged biexciton states in a single QD level, and the corresponding ratios between the two states agree with the theoretical predictions of the asymmetric band structures of CdSe-based QDs. Furthermore, the surface traps are found to provide additional nonradiative recombination pathways for the biexcitons, and their contributions are quantified by the method.
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Affiliation(s)
- Bin Li
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
- Key Laboratory of Spectral Measurement and Analysis of Shanxi Province, College of Physics and Information Engineering, Shanxi Normal University, Linfen 041004, China
| | - Guofeng Zhang
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Yong Zhang
- Department of Electrical and Computer Engineering, University of North Carolina at Charlotte, Charlotte, North Carolina 28223, United States
| | - Changgang Yang
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Wenli Guo
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Yonggang Peng
- School of Physics, Shandong University, Jinan 250100, China
| | - Ruiyun Chen
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Chengbing Qin
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Yan Gao
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Jianyong Hu
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Ruixiang Wu
- Key Laboratory of Spectral Measurement and Analysis of Shanxi Province, College of Physics and Information Engineering, Shanxi Normal University, Linfen 041004, China
| | - Jie Ma
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Haizheng Zhong
- Beijing Key Laboratory of Nanophotonics and Ultrafine Optoelectronic Systems, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Yujun Zheng
- School of Physics, Shandong University, Jinan 250100, China
| | - Liantuan Xiao
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Suotang Jia
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
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47
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Han X, Zhang G, Li B, Yang C, Guo W, Bai X, Huang P, Chen R, Qin C, Hu J, Ma Y, Zhong H, Xiao L, Jia S. Blinking Mechanisms and Intrinsic Quantum-Confined Stark Effect in Single Methylammonium Lead Bromide Perovskite Quantum Dots. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e2005435. [PMID: 33236844 DOI: 10.1002/smll.202005435] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 10/26/2020] [Indexed: 06/11/2023]
Abstract
Lead halide perovskite quantum dots (QDs) are promising materials for next-generation photoelectric devices because of their low preparation costs and excellent optoelectronic properties. In this study, the blinking mechanisms and the intrinsic quantum-confined Stark effect (IQCSE) in single organic-inorganic hybrid CH3 NH3 PbBr3 perovskite QDs using single-dot photoluminescence (PL) spectroscopy is investigated. The PL quantum yield-recombination rates distribution map allows the identification of different PL blinking mechanisms and their respective contributions to the PL emission behavior. A strong correlation between the excitation power and the blinking mechanisms is reported. Most single QDs exhibit band-edge carrier blinking under a low excitation photon fluence. While under a high excitation photon fluence, different proportions of Auger-blinking emerge in their PL intensity trajectories. In particular, significant IQCSEs in the QDs that exhibit more pronounced Auger-blinking are observed. Based on these findings, an Auger-induced IQCSE model to explain the observed IQCSE phenomena is observed.
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Affiliation(s)
- Xue Han
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Guofeng Zhang
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Bin Li
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
- Key Laboratory of Spectral Measurement and Analysis of Shanxi Province, College of Physics and Information Engineering, Shanxi Normal University, Linfen, 041004, China
| | - Changgang Yang
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Wenli Guo
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Xiuqing Bai
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Peng Huang
- Beijing Key Laboratory of Nanophotonics and Ultrafine Optoelectronic Systems, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing, 100081, China
| | - Ruiyun Chen
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Chengbing Qin
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Jianyong Hu
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Yifei Ma
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Haizheng Zhong
- Beijing Key Laboratory of Nanophotonics and Ultrafine Optoelectronic Systems, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing, 100081, China
| | - Liantuan Xiao
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Suotang Jia
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
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48
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Park J, Won YH, Kim T, Jang E, Kim D. Electrochemical Charging Effect on the Optical Properties of InP/ZnSe/ZnS Quantum Dots. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e2003542. [PMID: 32964676 DOI: 10.1002/smll.202003542] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 07/22/2020] [Indexed: 06/11/2023]
Abstract
Semiconductor quantum dots (QDs) are spotlighted as a key type of emissive material for the next generation of light-emitting diodes (LEDs). This work presents the investigation of the electrochemical charging effect on the absorption and emission of the InP/ZnSe/ZnS QDs with different mid-shell thicknesses. The excitonic peak is gradually bleached during electrochemical charging, which is caused by 1Se (or 1Sh ) state filling when the electron (or hole) is injected into the InP core. Additional charges also lead to photoluminescence (PL) intensity reduction, however, it is greatly mitigated as the mid-shell thickness increases. Various PL measurements reveal that the PL reduction under electrochemical charging is attributed to the acoustic phonon-assisted Auger recombination. Here, the Auger recombination in QDs with a thick mid-shell is reduced under the electrochemically charged condition, indicating that QDs with larger volume are more stable emitters in charge-injecting devices such as LEDs. Furthermore, the negative and positive trion Auger recombination rate constants are estimated, respectively, via electrochemical charging. The negative trion Auger rate constants decrease with an increase in the mid-shell thickness increases, whereas the positive trion Auger rate constants are not heavily reliant on the mid-shell thickness.
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Affiliation(s)
- Jumi Park
- Department of Chemistry, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - Yu-Ho Won
- Samsung Advanced Institute of Technology, Samsung Electronics, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do, 16678, Republic of Korea
| | - Taehyung Kim
- Samsung Advanced Institute of Technology, Samsung Electronics, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do, 16678, Republic of Korea
| | - Eunjoo Jang
- Samsung Advanced Institute of Technology, Samsung Electronics, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do, 16678, Republic of Korea
| | - Dongho Kim
- Department of Chemistry, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
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49
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Ko J, Chang JH, Jeong BG, Kim HJ, Joung JF, Park S, Choi DH, Bae WK, Bang J. Direct Photolithographic Patterning of Colloidal Quantum Dots Enabled by UV-Crosslinkable and Hole-Transporting Polymer Ligands. ACS APPLIED MATERIALS & INTERFACES 2020; 12:42153-42160. [PMID: 32813490 DOI: 10.1021/acsami.0c11988] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Quantum dot (QD)-based displays call for nondestructive, high-throughput, and high-resolution patterning techniques with micrometer precision. In particular, self-emissive QD-based displays demand fine patterns of conductive QD films with uniform thickness at the nanometer scale. To meet these requirements, we functionalized QDs with photopatternable and semiconducting poly(vinyltriphenylamine-random-azidostyrene) (PTPA-N3-SH) ligands in which hole-transporting triphenylamine and UV-crosslinkable azide (-N3) groups are integrated. The hybridized QD films undergo chemical crosslinking upon UV irradiation without loss in the luminescence efficiency, enabling micrometer-scale QD patterns (pitch size down to ∼10 μm) via direct photolithography. In addition, the conjugated moieties in the ligands allow the crosslinked QD films to be used in electrically driven light-emitting diodes (LED). As the ultimate achievement, a patterned QD-LED was prepared with a maximum luminance of 11 720 cd m-2 and a maximum external quantum efficiency (EQE) of 6.25%. The present study offers a simple platform to fabricate conductive nanoparticle films with micrometer-scale patterns, and thus we anticipate that this system will expedite the realization of QD-based displays and will also be applicable to the manufacture of nanoparticles for other electronic devices.
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Affiliation(s)
- Jaewan Ko
- Department of Chemical and Biological Engineering, Korea University, Seoul 02841, Republic of Korea
| | - Jun Hyuk Chang
- SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University, Suwon 16419, Gyeonggi, Republic of Korea
| | - Byeong Guk Jeong
- SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University, Suwon 16419, Gyeonggi, Republic of Korea
| | - Hyung Jong Kim
- Department of Chemistry, Korea University, Seoul 02841, Republic of Korea
| | - Joonyoung F Joung
- Department of Chemistry, Korea University, Seoul 02841, Republic of Korea
| | - Sungnam Park
- Department of Chemistry, Korea University, Seoul 02841, Republic of Korea
| | - Dong Hoon Choi
- Department of Chemistry, Korea University, Seoul 02841, Republic of Korea
| | - Wan Ki Bae
- SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University, Suwon 16419, Gyeonggi, Republic of Korea
| | - Joona Bang
- Department of Chemical and Biological Engineering, Korea University, Seoul 02841, Republic of Korea
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50
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Morozov S, Pensa EL, Khan AH, Polovitsyn A, Cortés E, Maier SA, Vezzoli S, Moreels I, Sapienza R. Electrical control of single-photon emission in highly charged individual colloidal quantum dots. SCIENCE ADVANCES 2020; 6:6/38/eabb1821. [PMID: 32948584 PMCID: PMC7500932 DOI: 10.1126/sciadv.abb1821] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 07/27/2020] [Indexed: 05/30/2023]
Abstract
Electron transfer to an individual quantum dot promotes the formation of charged excitons with enhanced recombination pathways and reduced lifetimes. Excitons with only one or two extra charges have been observed and exploited for very efficient lasing or single-quantum dot light-emitting diodes. Here, by room-temperature time-resolved experiments on individual giant-shell CdSe/CdS quantum dots, we show the electrochemical formation of highly charged excitons containing more than 12 electrons and 1 hole. We report the control over intensity blinking, along with a deterministic manipulation of quantum dot photodynamics, with an observed 210-fold increase in the decay rate, accompanied by 12-fold decrease in the emission intensity, while preserving single-photon emission characteristics. These results pave the way for deterministic control over the charge state, and room-temperature decay rate engineering for colloidal quantum dot-based classical and quantum communication technologies.
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Affiliation(s)
- Sergii Morozov
- The Blackett Laboratory, Department of Physics, Imperial College London, London SW7 2BW, UK
| | - Evangelina L Pensa
- The Blackett Laboratory, Department of Physics, Imperial College London, London SW7 2BW, UK
| | - Ali Hossain Khan
- Department of Chemistry, Ghent University, Krijgslaan 281-S3, Gent 9000, Belgium
| | - Anatolii Polovitsyn
- Department of Chemistry, Ghent University, Krijgslaan 281-S3, Gent 9000, Belgium
| | - Emiliano Cortés
- Chair in Hybrid Nanosystems, Nano-Institute Munich, Faculty of Physics, Ludwig-Maxilimians-Universität München, München 80539, Germany
| | - Stefan A Maier
- The Blackett Laboratory, Department of Physics, Imperial College London, London SW7 2BW, UK
- Chair in Hybrid Nanosystems, Nano-Institute Munich, Faculty of Physics, Ludwig-Maxilimians-Universität München, München 80539, Germany
| | - Stefano Vezzoli
- The Blackett Laboratory, Department of Physics, Imperial College London, London SW7 2BW, UK
| | - Iwan Moreels
- Department of Chemistry, Ghent University, Krijgslaan 281-S3, Gent 9000, Belgium
| | - Riccardo Sapienza
- The Blackett Laboratory, Department of Physics, Imperial College London, London SW7 2BW, UK.
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