1
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Wang X, Gao Y, Liu X, Xu H, Liu R, Song J, Li B, Shen H, Fan F. Strong high-energy exciton electroluminescence from the light holes of polytypic quantum dots. Nat Commun 2024; 15:6334. [PMID: 39068151 PMCID: PMC11283451 DOI: 10.1038/s41467-024-50432-8] [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: 12/20/2023] [Accepted: 07/10/2024] [Indexed: 07/30/2024] Open
Abstract
High-energy exciton emission could allow single-component multi-colour display or white light-emitting diodes. However, the thermal relaxation of high-energy excitons is much faster than the photon emission of them, making them non-emissive. Here, we report quantum dots with light hole-heavy hole splitting exhibiting strong high-energy exciton electroluminescence from high-lying light holes, opening a gate for high-performance multi-colour light sources. The high-energy electroluminescence can reach 44.5% of the band-edge heavy-hole exciton emission at an electron flux density Φe of 0.71 × 1019 s-1 cm-2 - 600 times lower than the photon flux density Φp (4.3 × 1021 s-1 cm-2) required for the similar ratio. Our simulation and experimental results suggest that the oscillator strength of heavy holes reduces more than that of light holes under electric fields. We attribute this as the main reason for strong light-hole electroluminescence. We observe this phenomenon in both CdxZn1-xSe-ZnS and CdSe-CdS core-shell quantum dots exhibiting large light hole-heavy hole splittings.
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Affiliation(s)
- Xingzhi Wang
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, China
- Anhui Province Key Laboratory of Scientific Instrument Development and Application, University of Science and Technology of China, Hefei, China
| | - Yan Gao
- Key Laboratory for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, Henan University, Kaifeng, China
| | - Xiaonan Liu
- Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications, Experimental Center of Advanced Materials, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing, China
| | - Huaiyu Xu
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, China
- Anhui Province Key Laboratory of Scientific Instrument Development and Application, University of Science and Technology of China, Hefei, China
| | - Ruixiang Liu
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, China
- Anhui Province Key Laboratory of Scientific Instrument Development and Application, University of Science and Technology of China, Hefei, China
| | - Jiaojiao Song
- Key Laboratory for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, Henan University, Kaifeng, China
| | - Bo Li
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei, China.
- Hefei National Laboratory, University of Science and Technology of China, Hefei, China.
- Anhui Province Key Laboratory of Scientific Instrument Development and Application, University of Science and Technology of China, Hefei, 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, Henan University, Kaifeng, China.
| | - Fengjia Fan
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei, China.
- Hefei National Laboratory, University of Science and Technology of China, Hefei, China.
- Anhui Province Key Laboratory of Scientific Instrument Development and Application, University of Science and Technology of China, Hefei, China.
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2
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Jung D, Park JW, Min S, Lee HJ, Park JS, Kim GM, Shin D, Im S, Lim J, Kim KH, Chae JA, Lee DC, Pugin R, Bulliard X, Hwang E, Park JS, Park YS, Bae WK. Strain-graded quantum dots with spectrally pure, stable and polarized emission. Nat Commun 2024; 15:5561. [PMID: 38956100 PMCID: PMC11220006 DOI: 10.1038/s41467-024-49791-z] [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: 12/18/2023] [Accepted: 06/18/2024] [Indexed: 07/04/2024] Open
Abstract
Structural deformation modifies the bandgap, exciton fine structure and phonon energy of semiconductors, providing an additional knob to control their optical properties. The impact can be exploited in colloidal semiconductor quantum dots (QDs), wherein structural stresses can be imposed in three dimensions while defect formation is suppressed by controlling surface growth kinetics. Yet, the control over the structural deformation of QDs free from optically active defects has not been reached. Here, we demonstrate strain-graded CdSe-ZnSe core-shell QDs with compositionally abrupt interface by the coherent pseudomorphic heteroepitaxy. Resulting QDs tolerate mutual elastic deformation of varying magnitudes at the interface with high structural fidelity, allowing for spectrally stable and pure emission of photons at accelerated rates with near unity luminescence efficiency. We capitalize on the asymmetric strain effect together with the quantum confinement effect to expand emission envelope of QDs spanning the entire visible region and exemplify their use in photonic applications.
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Affiliation(s)
- Dongju Jung
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Jeong Woo Park
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Sejong Min
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Hak June Lee
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Jin Su Park
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Gui-Min Kim
- Department of Chemical and Biomolecular Engineering, KAIST Institute for the Nanocentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Doyoon Shin
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Seongbin Im
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Jaemin Lim
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Ka Hyung Kim
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Jong Ah Chae
- Department of Display Engineering, Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Doh C Lee
- Department of Chemical and Biomolecular Engineering, KAIST Institute for the Nanocentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Raphaël Pugin
- Centre Suisse d'Electronique et de Microtechnique (CSEM SA), CH-2002, Neuchatel, Switzerland
| | - Xavier Bulliard
- Centre Suisse d'Electronique et de Microtechnique (CSEM SA), CH-2002, Neuchatel, Switzerland.
| | - Euyheon Hwang
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Ji-Sang Park
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea.
| | - Young-Shin Park
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.
| | - Wan Ki Bae
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea.
- Department of Display Engineering, Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea.
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3
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Stam M, Almeida G, Ubbink RF, van der Poll LM, Vogel YB, Chen H, Giordano L, Schiettecatte P, Hens Z, Houtepen AJ. Near-Unity Photoluminescence Quantum Yield of Core-Only InP Quantum Dots via a Simple Postsynthetic InF 3 Treatment. ACS NANO 2024; 18:14685-14695. [PMID: 38773944 PMCID: PMC11155241 DOI: 10.1021/acsnano.4c03290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2024] [Revised: 05/06/2024] [Accepted: 05/15/2024] [Indexed: 05/24/2024]
Abstract
Indium phosphide (InP) quantum dots (QDs) are considered the most promising alternative for Cd and Pb-based QDs for lighting and display applications. However, while core-only QDs of CdSe and CdTe have been prepared with near-unity photoluminescence quantum yield (PLQY), this is not yet achieved for InP QDs. Treatments with HF have been used to boost the PLQY of InP core-only QDs up to 85%. However, HF etches the QDs, causing loss of material and broadening of the optical features. Here, we present a simple postsynthesis HF-free treatment that is based on passivating the surface of the InP QDs with InF3. For optimized conditions, this results in a PLQY as high as 93% and nearly monoexponential photoluminescence decay. Etching of the particle surface is entirely avoided if the treatment is performed under stringent acid-free conditions. We show that this treatment is applicable to InP QDs with various sizes and InP QDs obtained via different synthesis routes. The optical properties of the resulting core-only InP QDs are on par with InP/ZnSe/ZnS core-shell QDs, with significantly higher absorption coefficients in the blue, and with potential for faster charge transport. These are important advantages when considering InP QDs for use in micro-LEDs or photodetectors.
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Affiliation(s)
- Maarten Stam
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The
Netherlands
| | - Guilherme Almeida
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The
Netherlands
| | - Reinout F. Ubbink
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The
Netherlands
| | - Lara M. van der Poll
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The
Netherlands
| | - Yan B. Vogel
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The
Netherlands
| | - Hua Chen
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The
Netherlands
| | - Luca Giordano
- Physics
and Chemistry of Nanostructures, Department of Chemistry, Ghent University, 9000 Gent, Belgium
| | - Pieter Schiettecatte
- Physics
and Chemistry of Nanostructures, Department of Chemistry, Ghent University, 9000 Gent, Belgium
| | - Zeger Hens
- Physics
and Chemistry of Nanostructures, Department of Chemistry, Ghent University, 9000 Gent, Belgium
| | - Arjan J. Houtepen
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The
Netherlands
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4
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Ma S, Cao F, Jia G, Wu Q, Wang S, Yang X. Blue ZnSeTe quantum dot light-emitting diodes with low efficiency roll-off enabled by an in situ hybridization of ZnMgO nanoparticles and amino alcohol molecules. NANOSCALE 2024; 16:10441-10447. [PMID: 38742531 DOI: 10.1039/d4nr01515k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
ZnSeTe quantum dots (QDs) have been employed as promising emitters for blue QD-based light-emitting diodes (QLEDs) due to their unique optoelectronic properties and environmental friendliness. However, such QLEDs usually suffer from serious efficiency roll-off primarily stemming from exciton loss at the interface of the QD layer and the ZnMgO (ZMO) electron transport layer (ETL), which remarkably hinders their application in flat-panel displays. Herein, we propose an in situ hybridization strategy that involves the pre-introduction of amino alcohols into the reaction solution. This strategy effectively suppresses the nucleophilic condensation process by facilitating the coordination of ammonium and hydroxyl groups with metal cations (M2+, i.e. Zn2+ and Mg2+). It slows down the growth rate of ZMO nanoparticles (NPs) while simultaneously facilitating M-O coordination, resulting in the synthesis of small-sized and low-defect ZMO NPs. Notably, this in situ hybridization approach not only alleviates emission quenching at the QDs/ETL interface but also elevates the energy level of the ETL for enhancing carrier injection. We further investigated the impact of amino alcohols with varying carbon-chain lengths on the performance of ZMO NPs and the corresponding LED devices. The optimal blue ZnSeTe QLED demonstrates an impressive EQE of 8.6% with only an ∼11% drop when the current density is increased to 200 mA cm-2, and the device operating lifetime extends to over 1300 h. Conversely, the device utilizing traditionally post-treated ZMO NPs as the ETL exhibits 45% efficiency roll-off and device lifetime of merely 190 h.
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Affiliation(s)
- Shaolin Ma
- Shanghai University Microelectronic R&D Center, Shanghai University, Shanghai 201900, P. R. China
- Key Laboratory of Advanced Display and System Applications of Ministry of Education, Shanghai University, Shanghai 200072, P. R. China.
| | - Fan Cao
- Key Laboratory of Advanced Display and System Applications of Ministry of Education, Shanghai University, Shanghai 200072, P. R. China.
| | - Guohua Jia
- School of Molecular and Life Sciences, Curtin University, Bentley, WA 6102, Australia
| | - Qianqian Wu
- Key Laboratory of Advanced Display and System Applications of Ministry of Education, Shanghai University, Shanghai 200072, P. R. China.
| | - Sheng Wang
- Key Laboratory of Advanced Display and System Applications of Ministry of Education, Shanghai University, Shanghai 200072, P. R. China.
| | - Xuyong Yang
- Key Laboratory of Advanced Display and System Applications of Ministry of Education, Shanghai University, Shanghai 200072, P. R. China.
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5
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Baek GW, Kim YJ, Kim J, Chang JH, Kim U, An S, Park J, Yu S, Bae WK, Lim J, Lee SY, Kwak J. Memristive Switching Mechanism in Colloidal InP/ZnSe/ZnS Quantum Dot-Based Synaptic Devices for Neuromorphic Computing. NANO LETTERS 2024; 24:5855-5861. [PMID: 38690800 DOI: 10.1021/acs.nanolett.4c01083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2024]
Abstract
Quantum dots (QDs) have garnered a significant amount of attention as promising memristive materials owing to their size-dependent tunable bandgap, structural stability, and high level of applicability for neuromorphic computing. Despite these advantageous properties, the development of QD-based memristors has been hindered by challenges in understanding and adjusting the resistive switching (RS) behavior of QDs. Herein, we propose three types of InP/ZnSe/ZnS QD-based memristors to elucidate the RS mechanism, employing a thin poly(methyl methacrylate) layer. This approach not only allows us to identify which carriers (electron or hole) are trapped within the QD layer but also successfully demonstrates QD-based synaptic devices. Furthermore, to utilize the QD memristor as a synapse, long-term potentiation/depression (LTP/LTD) characteristics are measured, resulting in a low nonlinearity of LTP/LTD at 0.1/1. On the basis of the LTP/LTD characteristics, single-layer perceptron simulations were performed using the Extended Modified National Institute of Standards and Technology, verifying a maximum recognition rate of 91.46%.
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Affiliation(s)
- Geun Woo Baek
- Department of Electrical and Computer Engineering, Inter-university Semiconductor Research Center, and SOFT Foundry Institute, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Yeon Jun Kim
- Department of Electrical and Computer Engineering, Inter-university Semiconductor Research Center, and SOFT Foundry Institute, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Jaekwon Kim
- Department of Electrical and Computer Engineering, Inter-university Semiconductor Research Center, and SOFT Foundry Institute, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Jun Hyuk Chang
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, 2066, Seobu-ro, Jangan-gu, Suwon, Gyeonggi-do 16419, Republic of Korea
| | - Uhjin Kim
- Department of Energy Science, Centre for Artificial Atoms, Sungkyunkwan University, 2066, Seobu-ro, Jangan-gu, Suwon, Gyeonggi-do 16419, Republic of Korea
| | - Soobin An
- Department of Electrical and Computer Engineering, Inter-university Semiconductor Research Center, and SOFT Foundry Institute, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Junhyeong Park
- Department of Electrical and Computer Engineering, Inter-university Semiconductor Research Center, and SOFT Foundry Institute, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Sunkyu Yu
- Intelligent Wave Systems Laboratory, Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, Republic of Korea
| | - Wan Ki Bae
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, 2066, Seobu-ro, Jangan-gu, Suwon, Gyeonggi-do 16419, Republic of Korea
| | - Jaehoon Lim
- Department of Energy Science, Centre for Artificial Atoms, and SKKU Institute of Energy Science and Technology (SIEST), and Department of Future Energy Engineering (DFEE), Sungkyunkwan University, 2066, Seobu-ro, Jangan-gu, Suwon, Gyeonggi-do 16419, Republic of Korea
| | - Soo-Yeon Lee
- Department of Electrical and Computer Engineering, Inter-university Semiconductor Research Center, and SOFT Foundry Institute, Seoul National University, 1, Gwanak-ro, Gwanak-gu, 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, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
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6
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Li Q, Wu K, Zhu H, Yang Y, He S, Lian T. Charge Transfer from Quantum-Confined 0D, 1D, and 2D Nanocrystals. Chem Rev 2024; 124:5695-5763. [PMID: 38629390 PMCID: PMC11082908 DOI: 10.1021/acs.chemrev.3c00742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 03/29/2024] [Accepted: 04/02/2024] [Indexed: 05/09/2024]
Abstract
The properties of colloidal quantum-confined semiconductor nanocrystals (NCs), including zero-dimensional (0D) quantum dots, 1D nanorods, 2D nanoplatelets, and their heterostructures, can be tuned through their size, dimensionality, and material composition. In their photovoltaic and photocatalytic applications, a key step is to generate spatially separated and long-lived electrons and holes by interfacial charge transfer. These charge transfer properties have been extensively studied recently, which is the subject of this Review. The Review starts with a summary of the electronic structure and optical properties of 0D-2D nanocrystals, followed by the advances in wave function engineering, a novel way to control the spatial distribution of electrons and holes, through their size, dimension, and composition. It discusses the dependence of NC charge transfer on various parameters and the development of the Auger-assisted charge transfer model. Recent advances in understanding multiple exciton generation, decay, and dissociation are also discussed, with an emphasis on multiple carrier transfer. Finally, the applications of nanocrystal-based systems for photocatalysis are reviewed, focusing on the photodriven charge separation and recombination processes that dictate the function and performance of these materials. The Review ends with a summary and outlook of key remaining challenges and promising future directions in the field.
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Affiliation(s)
- Qiuyang Li
- Department
of Physics, University of Michigan, 450 Church St, Ann Arbor, Michigan 48109, United States
| | - Kaifeng Wu
- State
Key Laboratory of Molecular Reaction Dynamics and Collaborative Innovation
Center of Chemistry for Energy Materials (iChEM), Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, China
- University
of Chinese Academy of Sciences, Beijing 100049, China
| | - Haiming Zhu
- Department
of Chemistry, Zhejiang University, Hangzhou, Zhejiang 310027, China
| | - Ye Yang
- The
State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM
(Collaborative Innovation Center of Chemistry for Energy Materials),
College of Chemistry & Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Sheng He
- Department
of Chemistry, Emory University, Atlanta, Georgia 30322, United States
| | - Tianquan Lian
- Department
of Chemistry, Emory University, Atlanta, Georgia 30322, United States
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7
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Zhang H, Liu J, Besteiro LV, Selopal GS, Zhao Z, Sun S, Rosei F. Advanced Interface Engineering in Gradient Core/Shell Quantum Dots Enables Efficient Photoelectrochemical Hydrogen Evolution. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2306203. [PMID: 38128031 DOI: 10.1002/smll.202306203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Revised: 11/19/2023] [Indexed: 12/23/2023]
Abstract
Semiconductor core/shell quantum dots (QDs) are considered promising building blocks to fabricate photoelectrochemical (PEC) cells for the direct conversion of solar energy into hydrogen (H2). However, the lattice mismatch between core and shell in such QDs results in undesirable defects and severe carrier recombination, limiting photo-induced carrier separation/transfer and solar-to-fuel conversion efficiency. Here, an interface engineering approach is explored to minimize the core-shell lattice mismatch in CdS/CdSexS1-x (x = 0.09-1) core/shell QDs (g-CSG). As a proof-of-concept, PEC cells based on g-CSG QDs yield a remarkable photocurrent density of 13.1 mA cm-2 under AM 1.5 G one-sun illumination (100 mW cm-2), which is ≈54.1% and ≈33.7% higher compared to that in CdS/CdSe0.5S0.5 (g-CSA) and CdS/CdSe QDs (g-CS), respectively. Theoretical calculations and carrier dynamics confirm more efficient carrier separation and charge transfer rate in g-CSG QDs with respect to g-CSA and g-CS QDs. These results are attributed to the minimization of the core-shell lattice mismatch by the cascade gradient shell in g-CSG QDs, which modifies carrier confinement potential and reduces interfacial defects. This work provides fundamental insights into the interface engineering of core/shell QDs and may open up new avenues to boost the performance of PEC cells for H2 evolution and other QDs-based optoelectronic devices.
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Affiliation(s)
- Hui Zhang
- School of Advanced Materials and Nanotechnology, Xidian University, Xi'an, 710126, P. R. China
| | - Jiabin Liu
- Institut National de la Recherche Scientifique, Centre Énergie Matériaux Télécommunications, 1650 Boulevard Lionel-Boulet, Varennes, Québec, J3X 1P7, Canada
| | | | - Gurpreet S Selopal
- Institut National de la Recherche Scientifique, Centre Énergie Matériaux Télécommunications, 1650 Boulevard Lionel-Boulet, Varennes, Québec, J3X 1P7, Canada
- Department of Engineering, Faculty of Agriculture, Dalhousie University, Truro, NS, B2N 5E3, Canada
| | - Zhenhuan Zhao
- School of Advanced Materials and Nanotechnology, Xidian University, Xi'an, 710126, P. R. China
| | - Shuhui Sun
- Institut National de la Recherche Scientifique, Centre Énergie Matériaux Télécommunications, 1650 Boulevard Lionel-Boulet, Varennes, Québec, J3X 1P7, Canada
| | - Federico Rosei
- Institut National de la Recherche Scientifique, Centre Énergie Matériaux Télécommunications, 1650 Boulevard Lionel-Boulet, Varennes, Québec, J3X 1P7, Canada
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8
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Zhao K, Zhou X, Li X, Moon J, Cassidy J, Harankahage D, Hu Z, Savoy SM, Gu Q, Zamkov M, Malko AV. Green Light from Red-Emitting Nanocrystals: Broadband, Low-Threshold Lasing from Colloidal Quantum Shells in Optical Nanocavities. ACS NANO 2024; 18:10946-10953. [PMID: 38613507 DOI: 10.1021/acsnano.4c02346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/15/2024]
Abstract
Spherical semiconductor nanoplatelets, known as quantum shells (QSs), have captured significant interest for their strong suppression of Auger recombination, which leads to long multiexciton lifetimes and wide optical gain bandwidth. Yet, the realization of benefits associated with the multiexciton lasing regime using a suitably designed photonic cavity remains elusive. Here, we demonstrate broadly tunable lasing from close-packed films of CdS/CdSe/CdS QSs deposited over nanopillar arrays on Si substrates. Wide spectral tuning of the stimulated emission in QSs with a fixed bandgap value was achieved by engaging single exciton (λX ∼ 634 nm), biexciton (λBX ∼ 627 nm), and multiple exciton (λMX ∼ 615-565 nm) transitions. The ensemble-averaged gain threshold of ∼ 2.6 electron-hole pairs per QS particle and the low photonic cavity fluence threshold of ∼4 μJ/cm2 were attributed to Auger suppression. The tuning of the lasing emission closely aligns with our model predictions achieved by varying the array period while preserving mode confinement and quality (Q) factors. These results mark a notable step toward the development of colloidal nanocrystal lasers.
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Affiliation(s)
- Kehui Zhao
- Department of Physics, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Xiaohe Zhou
- Department of Physics, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Xi Li
- Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Jiyoung Moon
- Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - James Cassidy
- The Center for Photochemical Sciences and Department of Physics, Bowling Green State University, Bowling Green, Ohio 43403, United States
| | - Dulanjan Harankahage
- The Center for Photochemical Sciences and Department of Physics, Bowling Green State University, Bowling Green, Ohio 43403, United States
| | - Zhongjian Hu
- Nanohmics Inc., 6201 E. Oltorf, Suite 400, Austin, Texas 78741, United States
| | - Steve M Savoy
- Nanohmics Inc., 6201 E. Oltorf, Suite 400, Austin, Texas 78741, United States
| | - Qing Gu
- Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, North Carolina 27695, United States
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Mikhail Zamkov
- The Center for Photochemical Sciences and Department of Physics, Bowling Green State University, Bowling Green, Ohio 43403, United States
| | - Anton V Malko
- Department of Physics, The University of Texas at Dallas, Richardson, Texas 75080, United States
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9
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Ba G, Yang Y, Huang F, Wang J, Lu Y, Li J, Cheng C, Sui M, Tian J. Gradient Alloy Shell Enabling Colloidal Quantum Wells Light-Emitting Diodes with Efficiency Exceeding 22. NANO LETTERS 2024; 24:4454-4461. [PMID: 38572779 DOI: 10.1021/acs.nanolett.4c00276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/05/2024]
Abstract
Colloidal quantum well (CQW) based light emitting diodes (LEDs) possess extra-high theoretical efficiency, but their performance still lags far behind conventional LEDs due to severe exciton quenching and unbalanced charge injection. Herein, we devised a gradient composition CdxZn1-xS shell to address these issues. The epitaxial shell with gradient composition was achieved through controlling competition between Cd2+ and Zn2+ cations to preferentially bind to the anions S2-. Thus, exciton quenching was suppressed greatly by passivating defects and reducing nonradiative recombination, thereby achieving near-unity photoluminescence quantum yield (PLQY). The gradient energy level of the shell reduced the hole injection barriers and increased the hole injection efficiency to balance the charge injection of LEDs. As a result, the LEDs achieved a high external quantum efficiency (EQE) of 22.83%, luminance of 111,319 cd/m2 and a long operational lifetime (T95@100 cd/m2) over 6,500 h, demonstrating the state-of-the-art performance for the CQW based LEDs.
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Affiliation(s)
- Guohang Ba
- Institute for Advanced Materials and Technology, University of Science and Technology Beijing,, Beijing 100083, China
| | - Yumin Yang
- Institute for Advanced Materials and Technology, University of Science and Technology Beijing,, Beijing 100083, China
| | - Fei Huang
- Institute for Advanced Materials and Technology, University of Science and Technology Beijing,, Beijing 100083, China
| | - Junfeng Wang
- Institute for Advanced Materials and Technology, University of Science and Technology Beijing,, Beijing 100083, China
| | - Yue Lu
- Beijing Key Laboratory of Microstructure and Properties of Solids, Faculty of Materials and Manufacturing, Beijing University of Technology, Beijing 100124, China
| | - Jing Li
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Chunyan Cheng
- Institute for Advanced Materials and Technology, University of Science and Technology Beijing,, Beijing 100083, China
| | - Manling Sui
- Beijing Key Laboratory of Microstructure and Properties of Solids, Faculty of Materials and Manufacturing, Beijing University of Technology, Beijing 100124, China
| | - Jianjun Tian
- Institute for Advanced Materials and Technology, University of Science and Technology Beijing,, Beijing 100083, China
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10
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Wang X, Chen A, Wu X, Zhang J, Dong J, Zhang L. Synthesis and Modulation of Low-Dimensional Transition Metal Chalcogenide Materials via Atomic Substitution. NANO-MICRO LETTERS 2024; 16:163. [PMID: 38546814 PMCID: PMC10978568 DOI: 10.1007/s40820-024-01378-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 02/17/2024] [Indexed: 04/01/2024]
Abstract
In recent years, low-dimensional transition metal chalcogenide (TMC) materials have garnered growing research attention due to their superior electronic, optical, and catalytic properties compared to their bulk counterparts. The controllable synthesis and manipulation of these materials are crucial for tailoring their properties and unlocking their full potential in various applications. In this context, the atomic substitution method has emerged as a favorable approach. It involves the replacement of specific atoms within TMC structures with other elements and possesses the capability to regulate the compositions finely, crystal structures, and inherent properties of the resulting materials. In this review, we present a comprehensive overview on various strategies of atomic substitution employed in the synthesis of zero-dimensional, one-dimensional and two-dimensional TMC materials. The effects of substituting elements, substitution ratios, and substitution positions on the structures and morphologies of resulting material are discussed. The enhanced electrocatalytic performance and photovoltaic properties of the obtained materials are also provided, emphasizing the role of atomic substitution in achieving these advancements. Finally, challenges and future prospects in the field of atomic substitution for fabricating low-dimensional TMC materials are summarized.
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Affiliation(s)
- Xuan Wang
- Key Laboratory of Cluster Science, Ministry of Education of China, Beijing Key Laboratory of Photoelectronic and Electrophonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 100081, People's Republic of China
| | - Akang Chen
- Key Laboratory of Cluster Science, Ministry of Education of China, Beijing Key Laboratory of Photoelectronic and Electrophonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 100081, People's Republic of China
| | - XinLei Wu
- Key Laboratory of Cluster Science, Ministry of Education of China, Beijing Key Laboratory of Photoelectronic and Electrophonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 100081, People's Republic of China
| | - Jiatao Zhang
- Key Laboratory of Cluster Science, Ministry of Education of China, Beijing Key Laboratory of Photoelectronic and Electrophonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 100081, People's Republic of China.
| | - Jichen Dong
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry Chinese Academy of Sciences, Beijing, 100190, People's Republic of China.
| | - Leining Zhang
- Key Laboratory of Cluster Science, Ministry of Education of China, Beijing Key Laboratory of Photoelectronic and Electrophonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 100081, People's Republic of China.
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11
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Li H, Zhao Y, Qiu Y, Gao H, He K, Yang J, Zhao Y, OuYang G, Ma N, Wei X, Du Z, Jiang L, Wu Y. Multi-Interfacial Confined Assembly of Colloidal Quantum Dots Quasisuperlattice Microcavities for High-Resolution Full-Color Microlaser Arrays. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2314061. [PMID: 38350441 DOI: 10.1002/adma.202314061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 02/08/2024] [Indexed: 02/15/2024]
Abstract
Colloidal quantum dots (CQDs) are considered a promising material for the next generation of integrated display devices due to their designable optical bandgap and low energy consumption. Owing to their dispersibility in solvents, CQD micro/nanostructures are generally fabricated by solution-processing methods. However, the random mass transfer in liquid restricts the programmable construction in macroscopy and ordered assembly in microscopy for the integration of CQD optical structures. Herein, a multi-interfacial confined assembly strategy is developed to fabricate CQDs programmable microstructure arrays with a quasisuperlattice configuration through controlling the dynamics of three-phase contact lines (TPCLs). The motion of TPCLs dominates the division of liquid film for precise positioning of CQD microstructures, while pinned TPCLs control the solvent evaporation and concentration gradient to directionally drive the mass transfer and packing of CQDs. Owing to their long-range order and adjustable structural dimensions, CQD microring arrays function as high-quality-factor (high-Q) lasing resonant cavities with low thresholds and tunable lasing emission modes. Through the further surface treatment and liquid dynamics control, the on-chip integration of red (R), green (G), and blue (B) multicomponent CQD microlaser arrays are demonstrated. The technique establishes a new route to fabricate large-area, ultrahigh-definition, and full-color CQD laser displays.
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Affiliation(s)
- Hui Li
- Key Laboratory for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, Henan University, Kaifeng, 475004, P. R. China
- Key Laboratory of Bio-Inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Yuyan Zhao
- Suzhou Institute for Advanced Research, University of Science and Technology of China, Suzhou, Jiangsu, 215123, China
| | - Yuchen Qiu
- College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Hanfei Gao
- Suzhou Institute for Advanced Research, University of Science and Technology of China, Suzhou, Jiangsu, 215123, China
| | - Ke He
- Key Laboratory of Bio-Inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Future Technology, University of Chinese Academy of Sciences (UCAS), Beijing, 100049, P. R. China
| | - Junchuan Yang
- Suzhou Institute for Advanced Research, University of Science and Technology of China, Suzhou, Jiangsu, 215123, China
| | - Yingjie Zhao
- College of Chemistry, Zhengzhou University, Zhengzhou, 450001, P. R. China
| | - Guangwen OuYang
- Key Laboratory for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, Henan University, Kaifeng, 475004, P. R. China
| | - Na Ma
- Key Laboratory for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, Henan University, Kaifeng, 475004, P. R. China
| | - Xiao Wei
- Ji Hua Laboratory Foshan, Guangdong, 528200, P. R. China
| | - Zuliang Du
- Key Laboratory for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, Henan University, Kaifeng, 475004, P. R. China
| | - Lei Jiang
- Key Laboratory of Bio-Inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Future Technology, University of Chinese Academy of Sciences (UCAS), Beijing, 100049, P. R. China
| | - Yuchen Wu
- Key Laboratory for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, Henan University, Kaifeng, 475004, P. R. China
- Key Laboratory of Bio-Inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- Suzhou Institute for Advanced Research, University of Science and Technology of China, Suzhou, Jiangsu, 215123, China
- School of Future Technology, University of Chinese Academy of Sciences (UCAS), Beijing, 100049, P. R. China
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12
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Shin D, Lee HJ, Jung D, Chae JA, Park JW, Lim J, Im S, Min S, Hwang E, Lee DC, Park YS, Chang JH, Park K, Kim J, Park JS, Bae WK. Growth Control of InP/ZnSe Heterostructured Nanocrystals. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2312250. [PMID: 38300222 DOI: 10.1002/adma.202312250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 01/23/2024] [Indexed: 02/02/2024]
Abstract
The morphology of heterostructured semiconductor nanocrystals (h-NCs) dictates the spatial distribution of charge carriers and their recombination dynamics and/or transport, which are the main performance indicators of photonic applications utilizing h-NCs. The inability to control the morphology of heterovalent III-V/II-VI h-NCs composed of heavy-metal-free elements hinders their practical use. As a case study of III-V/II-VI h-NCs, the growth control of ZnSe epilayers on InP NCs is demonstrated here. The anisotropic morphology in InP/ZnSe h-NCs is attributed to the facet-dependent energy costs for the growth of ZnSe epilayers on different facets of InP NCs, and effective chemical means for controlling the growth rates of ZnSe on different surface planes are demonstrated. Ultimately, this article capitalizes on the controlled morphology of InP/ZnSe h-NCs to expand their photophysical characteristics from stable and pure emission to environment-sensitive one, which will facilitate their use in a variety of photonic applications.
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Affiliation(s)
- Doyoon Shin
- SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Hak June Lee
- SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Dongju Jung
- SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Jong Ah Chae
- SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Jeong Woo Park
- SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Jaemin Lim
- SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Seongbin Im
- SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Sejong Min
- SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Euyheon Hwang
- SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Doh C Lee
- Department of Chemical and Biomolecular Engineering, KAIST Institute for the Nanocentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Young-Shin Park
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Jun Hyuk Chang
- SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Kyoungwon Park
- Display Research Center, Korea Electronics Technology Institute (KETI), Seongnam, 13509, Republic of Korea
| | - Junki Kim
- SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Ji-Sang Park
- SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Wan Ki Bae
- SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
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13
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Li X, Du J, Zhao G, Zhang B, Livache C, Ahn N, Jia Y, Li M, Chen Y, Zhu J, Guo J, Klimov VI, Wu K. Two-Color Amplified Spontaneous Emission from Auger-Suppressed Quantum Dots in Liquids. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2308979. [PMID: 38009644 DOI: 10.1002/adma.202308979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2023] [Revised: 11/06/2023] [Indexed: 11/29/2023]
Abstract
Colloidal quantum-dot (QD) lasing is normally achieved in close-packed solid-state films, as a high QD volume fraction is required for stimulated emission to outcompete fast Auger decay of optical-gain-active multiexciton states. Here a new type of liquid optical-gain medium is demonstrated, in which compact compositionally-graded QDs (ccg-QDs) that feature strong suppression of Auger decay are liquefied using a small amount of solvent. Transient absorption measurements of ccg-QD liquid suspensions reveal broad-band optical gain spanning a wide spectral range from 560 (green) to 675 nm (red). The gain magnitude is sufficient to realize a two-color amplified spontaneous emission (ASE) at 637 and 594 nm due to the band-edge (1S) and the excited-state (1P) transition, respectively. Importantly, the ASE regime is achieved using quasicontinuous excitation with nanosecond pulses. Furthermore, the ASE is highly stable under prolonged excitation, which stands in contrast to traditional dyes that exhibit strong degradation under identical excitation conditions. These observations point toward a considerable potential of high-density ccg-QD suspensions as liquid, dye-like optical gain media that feature readily achievable spectral tunability and stable operation under intense photoexcitation.
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Affiliation(s)
- Xueyang Li
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, China
| | - Jun Du
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, China
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Guohui Zhao
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Boyu Zhang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, China
| | - Clément Livache
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Namyoung Ahn
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Yuxi Jia
- University of Chinese Academy of Sciences, Beijing, 100049, China
- CAS Key Laboratory of Chemical Lasers, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, China
| | - Mingrun Li
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, China
| | - Ying Chen
- CAS Key Laboratory of Chemical Lasers, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, China
| | - Jingyi Zhu
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, China
| | - Jingwei Guo
- University of Chinese Academy of Sciences, Beijing, 100049, China
- CAS Key Laboratory of Chemical Lasers, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, China
| | - Victor I Klimov
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Kaifeng Wu
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
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14
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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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15
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Tanghe I, Samoli M, Wagner I, Cayan SA, Khan AH, Chen K, Hodgkiss J, Moreels I, Thourhout DV, Hens Z, Geiregat P. Optical gain and lasing from bulk cadmium sulfide nanocrystals through bandgap renormalization. NATURE NANOTECHNOLOGY 2023; 18:1423-1429. [PMID: 37798564 DOI: 10.1038/s41565-023-01521-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 09/06/2023] [Indexed: 10/07/2023]
Abstract
Strongly confined colloidal quantum dots have been investigated for low-cost light emission and lasing for nearly two decades. However, known materials struggle to combine technologically relevant metrics of low-threshold and long inverted-state lifetime with a material gain coefficient fit to match cavity losses, particularly under electrical excitation. Here we show that bulk nanocrystals of CdS combine an exceptionally large material gain of 50,000 cm-1 with best-in-class gain thresholds below a single exciton per nanocrystal and 3 ns gain lifetimes not limited by non-radiative Auger processes. We quantitatively account for these findings by invoking a strong bandgap renormalization effect, unobserved in nanocrystals to date, to the best of our knowledge. Next, we demonstrate broadband amplified spontaneous emission and lasing under quasi-continuous-wave conditions. Our results highlight the prospects of bulk nanocrystals for lasing from solution-processable materials.
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Affiliation(s)
- Ivo Tanghe
- Photonics Research Group, Ghent University, Gent, Belgium
- NoLIMITS Center For Non-Linear Microscopy and Spectroscopy, Ghent University, Gent, Belgium
- Physics and Chemistry of Nanostructures, Ghent University, Gent, Belgium
| | - Margarita Samoli
- Physics and Chemistry of Nanostructures, Ghent University, Gent, Belgium
| | - Isabella Wagner
- School of Chemical and Physical Sciences, Victoria University of Wellington, Wellington, New Zealand
- MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington, New Zealand
| | - Servet Ataberk Cayan
- NoLIMITS Center For Non-Linear Microscopy and Spectroscopy, Ghent University, Gent, Belgium
- Physics and Chemistry of Nanostructures, Ghent University, Gent, Belgium
| | - Ali Hossain Khan
- Department of Chemical and Biological Sciences, S. N. Bose National Centre for Basic Sciences, Kolkata, India
- Ghent University, Physics and Chemistry of Nanostructures, Gent, Belgium
| | - Kai Chen
- MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington, New Zealand
- Robinson Research Institute, Victoria University of Wellington, Wellington, New Zealand
- The Dodd-Walls Centre for Photonic and Quantum Technologies, University of Otago, Dunedin, New Zealand
| | - Justin Hodgkiss
- School of Chemical and Physical Sciences, Victoria University of Wellington, Wellington, New Zealand
- MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington, New Zealand
| | - Iwan Moreels
- Physics and Chemistry of Nanostructures, Ghent University, Gent, Belgium
| | - Dries Van Thourhout
- Photonics Research Group, Ghent University, Gent, Belgium
- NoLIMITS Center For Non-Linear Microscopy and Spectroscopy, Ghent University, Gent, Belgium
| | - Zeger Hens
- NoLIMITS Center For Non-Linear Microscopy and Spectroscopy, Ghent University, Gent, Belgium
- Physics and Chemistry of Nanostructures, Ghent University, Gent, Belgium
| | - Pieter Geiregat
- NoLIMITS Center For Non-Linear Microscopy and Spectroscopy, Ghent University, Gent, Belgium.
- Physics and Chemistry of Nanostructures, Ghent University, Gent, Belgium.
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16
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Liu Y, Li Y, Gao K, Zhu J, Wu K. Sub-Single-Exciton Optical Gain in Lead Halide Perovskite Quantum Dots Revealed by Exciton Polarization Spectroscopy. J Am Chem Soc 2023; 145:25864-25873. [PMID: 37971813 DOI: 10.1021/jacs.3c10281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2023]
Abstract
Optical gain of colloidal quantum dots (QDs) is often attained in the multiexciton regime, which strongly complicates their lasing applications as the gain lifetime is limited by nonradiative Auger recombination occurring typically on the picosecond time scale. In principle, low-threshold gain can be achieved if the gain-active emission has a sizable red shift compared to the absorption. But, this mechanism has been rarely observed in typical QDs featuring small Stokes shift due to their weak electron-phonon coupling. Here, we report the observation of sub-single-exciton gain in CsPbI3 and CsPbBr3 perovskite QDs, which is unequivocally established through pinpointing the stimulated emission and biexciton absorption signatures using polarization-controlled femtosecond transient absorption spectroscopy. The soft lattice of perovskite QDs and hence strong electron-phonon coupling lead to two stimulated emission features from free and self-trapped excitons, respectively. In monodisperse QDs of varying sizes, the Stokes shift of the self-trapped exciton emission is sufficiently large to overcome the biexciton absorption loss and the inhomogeneous line width, enabling optical gain with average exciton occupancy down to <10%.
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Affiliation(s)
- Yuan Liu
- Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, China
| | - Yuxuan Li
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kaimin Gao
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jingyi Zhu
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, China
| | - Kaifeng Wu
- Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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17
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Liao C, Tang L, Jia Y, Sun S, Yang H, Xu J, Gu Z. Slow Auger Recombination in Ag 2Se Colloidal Quantum Dots. NANO LETTERS 2023; 23:9865-9871. [PMID: 37871258 DOI: 10.1021/acs.nanolett.3c02770] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
Efficient Auger recombination (AR) presents a significant challenge for the advancement of colloidal quantum dot (QD)-based devices involving multiexcitons. Here, the AR dynamics of near-infrared Ag2Se QDs were studied through transient absorption experiments. As the QD radius increases from 0.9 to 2.5 nm, the biexciton lifetime (τ2) of Ag2Se QDs increases from 35 to 736 ps, which is approximately 10 times longer than that of comparable-sized CdSe and PbSe QDs. A qualitative analysis based on observables indicates that the slow Auger rate is primarily attributed to the low density of the final states. The biexciton lifetime and triexciton lifetime (τ3) of Ag2Se QDs follow R3 and R2.6 dependence, respectively. Moreover, the ratio of τ2/τ3 is ∼2.3-3.2, which is markedly lower than the value expected from statistical scaling (4.5). These findings suggest that environmentally friendly Ag2Se QDs can serve as excellent candidates for low-threshold lasers and third-generation photovoltaics utilizing carrier multiplication.
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Affiliation(s)
- Chen Liao
- College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications, Nanjing 210023, China
| | - Luping Tang
- College of Mechanical and Electronic Engineering, Nanjing Forestry University, Nanjing 210037, China
- SEU-FEI Nano-Pico Center, Key Lab of MEMS of Ministry of Education, Southeast University, Nanjing 210096, China
| | - Yunzhe Jia
- College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications, Nanjing 210023, China
| | - Shaoling Sun
- Joint International Research Laboratory of Information Display and Visualization, School of Electronic Science and Engineering, Southeast University, Nanjing 210096, China
| | - Haoran Yang
- College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications, Nanjing 210023, China
| | - Jie Xu
- College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications, Nanjing 210023, China
| | - Zixuan Gu
- College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications, Nanjing 210023, China
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18
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Saenz N, Hamachi LS, Wolock A, Goodge BH, Kuntzmann A, Dubertret B, Billinge I, Kourkoutis LF, Muller DA, Crowther AC, Owen JS. Synthesis of graded CdS 1-xSe x nanoplatelet alloys and heterostructures from pairs of chalcogenoureas with tailored conversion reactivity. Chem Sci 2023; 14:12345-12354. [PMID: 37969574 PMCID: PMC10631235 DOI: 10.1039/d3sc03384h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 10/13/2023] [Indexed: 11/17/2023] Open
Abstract
A mixture of N,N,N'-trisubstituted thiourea and cyclic N,N,N',N'-tetrasubstituted selenourea precursors were used to synthesize three monolayer thick CdS1-xSex nanoplatelets in a single synthetic step. The microstructure of the nanoplatelets could be tuned from homogeneous alloys, to graded alloys to core/crown heterostructures depending on the relative conversion reactivity of the sulfur and selenium precursors. UV-visible absorption and photoluminescence spectroscopy and scanning transmission electron microscopy electron energy loss spectroscopy (STEM-EELS) images demonstrate that the elemental distribution is governed by the relative precursor conversion kinetics. Slow conversion kinetics produced nanoplatelets with larger lateral dimensions, behavior that is characteristic of precursor conversion limited growth kinetics. Across a 10-fold range of reactivity, CdS nanoplatelets have 4× smaller lateral dimensions than CdSe nanoplatelets grown under identical conversion kinetics. The difference in size is consistent with a rate of CdSe growth that is 4× greater than the rate of CdS. The influence of the relative sulfide and selenide growth rates, the duration of the nucleation phase, and the solute composition on the nanoplatelet microstructure are discussed.
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Affiliation(s)
- Natalie Saenz
- Department of Chemistry, Columbia University New York NY USA
| | | | - Anna Wolock
- Department of Chemistry, Barnard College, Columbia University New York NY USA
| | - Berit H Goodge
- School of Applied and Engineering Physics, Cornell University Ithaca NY 14853 USA
| | - Alexis Kuntzmann
- Ecole Supérieure de Physique et de Chimie Industrielle Paris France
| | - Benoit Dubertret
- Ecole Supérieure de Physique et de Chimie Industrielle Paris France
| | - Isabel Billinge
- Department of Chemistry, Columbia University New York NY USA
| | - Lena F Kourkoutis
- School of Applied and Engineering Physics, Cornell University Ithaca NY 14853 USA
- Kavli Institute at Cornell for Nanoscale Science, Cornell University Ithaca NY 14853 USA
| | - David A Muller
- School of Applied and Engineering Physics, Cornell University Ithaca NY 14853 USA
- Kavli Institute at Cornell for Nanoscale Science, Cornell University Ithaca NY 14853 USA
| | - Andrew C Crowther
- Department of Chemistry, Barnard College, Columbia University New York NY USA
| | - Jonathan S Owen
- Department of Chemistry, Columbia University New York NY USA
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19
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Gao Y, Li B, Liu X, Shen H, Song Y, Song J, Yan Z, Yan X, Chong Y, Yao R, Wang S, Li LS, Fan F, Du Z. Minimizing heat generation in quantum dot light-emitting diodes by increasing quasi-Fermi-level splitting. NATURE NANOTECHNOLOGY 2023; 18:1168-1174. [PMID: 37474685 DOI: 10.1038/s41565-023-01441-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Accepted: 06/02/2023] [Indexed: 07/22/2023]
Abstract
Minimizing heat accumulation is essential to prolonging the operational lifetime of quantum dot light-emitting diodes (QD-LEDs). Reducing heat generation at the source is the ideal solution, which requires high brightness and quantum efficiency at low driving voltages. Here we propose to enhance the brightness of QD-LEDs at low driving voltages by using a monolayer of large QDs to reduce the packing number in the emitting layer. This strategy allows us to achieve a higher charge population per QD for a given number of charges without charge leakage, enabling enhanced quasi-Fermi-level splitting and brightness at low driving voltage. Due to the minimized heat generation, these LEDs show a high power conversion efficiency of 23% and a T95 operation lifetime (the time for the luminance to decrease to 95% of the initial value) of more than 48,000 h at 1,000 cd m-2.
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Affiliation(s)
- Yan Gao
- Key Laboratory for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, Henan University, Kaifeng, China
| | - Bo Li
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Modern Physics, CAS Key Laboratory of Microscale Magnetic Resonance, Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, China
| | - Xiaonan Liu
- Key Laboratory for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, Henan University, Kaifeng, 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, Henan University, Kaifeng, China.
| | - Yang Song
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Modern Physics, CAS Key Laboratory of Microscale Magnetic Resonance, Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, China
| | - Jiaojiao Song
- Key Laboratory for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, Henan University, Kaifeng, China
| | - Zhijie Yan
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Modern Physics, CAS Key Laboratory of Microscale Magnetic Resonance, Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, China
| | - Xiaohan Yan
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Modern Physics, CAS Key Laboratory of Microscale Magnetic Resonance, Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, China
| | - Yihua Chong
- Key Laboratory for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, Henan University, Kaifeng, China
| | - Ruyun Yao
- Key Laboratory for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, Henan University, Kaifeng, China
| | - Shujie Wang
- Key Laboratory for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, Henan University, Kaifeng, China
| | - Lin Song Li
- Key Laboratory for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, Henan University, Kaifeng, China
| | - Fengjia Fan
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Modern Physics, CAS Key Laboratory of Microscale Magnetic Resonance, Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, China.
| | - Zuliang Du
- Key Laboratory for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, Henan University, Kaifeng, China.
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20
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Taghipour N, Dalmases M, Whitworth GL, Wang Y, Konstantatos G. Ultrafast Cascade Charge Transfer in Multibandgap Colloidal Quantum Dot Solids Enables Threshold Reduction for Optical Gain and Stimulated Emission. NANO LETTERS 2023; 23:8637-8642. [PMID: 37724790 DOI: 10.1021/acs.nanolett.3c02468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/21/2023]
Abstract
Achieving low-threshold infrared stimulated emission in solution-processed quantum dots is critical to enable real-life applications including photonic integrated circuits (PICs), LIDAR application, and optical telecommunication. However, realization of low threshold infrared gain is fundamentally challenging due to high degeneracy of the first emissive state (e.g., 8-fold) and fast Auger recombination. In this Letter, we demonstrate ultra-low-threshold infrared stimulated emission with an onset of 110 μJ cm-2 employing cascade charge transfer (CT) in Pb-chalcogenide colloidal quantum dot (CQD) solids. In doing so, we investigate this idea in two different architectures including a mixture of multiband gap CQDs and a layer-by-layer (LBL) configuration. Using transient absorption spectroscopy, we show ultrafast cascade CT from large band gap PbS CQD to small band gap PbS/PbSSe core/shell CQDs in LBL (∼2 ps) and mixture (∼9 ps) configurations. These results indicate the feasibility of using cascade CT as an efficient method to reduce the optical gain threshold in CQD solid films.
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Affiliation(s)
- Nima Taghipour
- ICFO, Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, 08860 Spain
| | - Mariona Dalmases
- ICFO, Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, 08860 Spain
| | - Guy Luke Whitworth
- ICFO, Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, 08860 Spain
| | - Yongjie Wang
- ICFO, Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, 08860 Spain
| | - Gerasimos Konstantatos
- ICFO, Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, 08860 Spain
- ICREA, Institució Catalana de Recerca i Estudis Avançats, Barcelona, 08010 Spain
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21
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Stam M, du Fossé I, Infante I, Houtepen AJ. Guilty as Charged: The Role of Undercoordinated Indium in Electron-Charged Indium Phosphide Quantum Dots. ACS NANO 2023; 17:18576-18583. [PMID: 37712414 PMCID: PMC10540256 DOI: 10.1021/acsnano.3c07029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 09/12/2023] [Indexed: 09/16/2023]
Abstract
Quantum dots (QDs) are known for their size-dependent optical properties, narrow emission bands, and high photoluminescence quantum yield (PLQY), which make them interesting candidates for optoelectronic applications. In particular, InP QDs are receiving a lot of attention since they are less toxic than other QD materials and are hence suitable for consumer applications. Most of these applications, such as LEDs, photovoltaics, and lasing, involve charging QDs with electrons and/or holes. However, charging of QDs is not easy nor innocent, and the effect of charging on the composition and properties of InP QDs is not yet well understood. This work provides theoretical insight into electron charging of the InP core and InP/ZnSe QDs. Density functional theory calculations are used to show that charging of InP-based QDs with electrons leads to the formation of trap states if the QD contains In atoms that are undercoordinated and thus have less than four bonds to neighboring atoms. InP core-only QDs have such atoms at the surface, which are responsible for the formation of trap states upon charging with electrons. We show that InP/ZnSe core-shell models with all In atoms fully coordinated can be charged with electrons without the formation of trap states. These results show that undercoordinated In atoms should be avoided at all times for QDs to be stably charged with electrons.
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Affiliation(s)
- Maarten Stam
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The
Netherlands
| | - Indy du Fossé
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The
Netherlands
| | - Ivan Infante
- BC
Materials, Basque Center for Materials, Applications, and Nanostructures, UPV/EHU Science Park, Leioa 48940, Spain
- Ikerbasque,
Basque Foundation for Science, Bilbao 48009, Spain
| | - Arjan J. Houtepen
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The
Netherlands
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22
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Beavon J, Huang J, Harankahage D, Montemurri M, Cassidy J, Zamkov M. Quantum shells versus quantum dots: suppressing Auger recombination in colloidal semiconductors. Chem Commun (Camb) 2023; 59:11337-11348. [PMID: 37676487 DOI: 10.1039/d3cc02091f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/08/2023]
Abstract
Colloidal semiconductor nanocrystals (NCs) have attracted a great deal of attention in recent decades. The quantum efficiency of many optoelectronic processes based on these nanomaterials, however, declines with increasing optical or electrical excitation intensity. This issue is caused by Auger recombination of multiple excitons, which converts the NC energy into excess heat, whereby reducing the efficiency and lifespan of NC-based devices, including lasers, photodetectors, X-ray scintillators, and high-brightness LEDs. Recently, semiconductor quantum shells (QSs) have emerged as a viable nanoscale architecture for the suppression of Auger decay. The spherical-shell geometry of these nanostructures leads to a significant reduction of Auger decay rates, while exhibiting a near unity photoluminescence quantum yield. Here, we compare the optoelectronic properties of quantum shells against other low-dimensional semiconductors and discuss their emerging opportunities in solid-state lighting and energy-harvesting applications.
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Affiliation(s)
- Jacob Beavon
- Department of Physics, Bowling Green State University, Bowling Green, Ohio 43403, USA
| | - Jiamin Huang
- The Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, USA.
- Department of Physics, Bowling Green State University, Bowling Green, Ohio 43403, USA
| | - Dulanjan Harankahage
- The Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, USA.
- Department of Chemistry, Bowling Green State University, Bowling Green, Ohio 43403, USA
| | - Michael Montemurri
- Department of Physics, Bowling Green State University, Bowling Green, Ohio 43403, USA
| | - James Cassidy
- The Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, USA.
- Department of Chemistry, Bowling Green State University, Bowling Green, Ohio 43403, USA
| | - Mikhail Zamkov
- The Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, USA.
- Department of Physics, Bowling Green State University, Bowling Green, Ohio 43403, USA
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23
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Chen Q, Qi Z, Lin J, Huang J, Xie G. Promise to electrically pumped colloidal quantum dot lasers. Innovation (N Y) 2023; 4:100498. [PMID: 37674512 PMCID: PMC10477796 DOI: 10.1016/j.xinn.2023.100498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 08/10/2023] [Indexed: 09/08/2023] Open
Affiliation(s)
- Qiyin Chen
- Sauvage Center for Molecular Sciences, Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, Department of Chemistry, Wuhan University, Wuhan 430072, China
- The Institute of Flexible Electronics (Future Technologies), Xiamen University, Xiamen 361005, China
| | - Zhiling Qi
- Sauvage Center for Molecular Sciences, Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, Department of Chemistry, Wuhan University, Wuhan 430072, China
- The Institute of Flexible Electronics (Future Technologies), Xiamen University, Xiamen 361005, China
| | - Jie Lin
- Oxford Suzhou Centre for Advanced Research (OSCAR), University of Oxford, Suzhou 215123, China
| | - Jingsong Huang
- Oxford Suzhou Centre for Advanced Research (OSCAR), University of Oxford, Suzhou 215123, China
| | - Guohua Xie
- Sauvage Center for Molecular Sciences, Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, Department of Chemistry, Wuhan University, Wuhan 430072, China
- The Institute of Flexible Electronics (Future Technologies), Xiamen University, Xiamen 361005, China
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24
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Abstract
Lasers and optical amplifiers based on solution-processable materials have been long-desired devices for their compatibility with virtually any substrate, scalability, and ease of integration with on-chip photonics and electronics. These devices have been pursued across a wide range of materials including polymers, small molecules, perovskites, and chemically prepared colloidal semiconductor nanocrystals, also commonly referred to as colloidal quantum dots. The latter materials are especially attractive for implementing optical-gain media as in addition to being compatible with inexpensive and easily scalable chemical techniques, they offer multiple advantages derived from a zero-dimensional character of their electronic states. These include a size-tunable emission wavelength, low optical gain thresholds, and weak sensitivity of lasing characteristics to variations in temperature. Here we review the status of colloidal nanocrystal lasing devices, most recent advances in this field, outstanding challenges, and the ongoing progress toward technological viable devices including colloidal quantum dot laser diodes.
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Affiliation(s)
- Namyoung Ahn
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Clément Livache
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Valerio Pinchetti
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Victor I Klimov
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
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25
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Lee HJ, Im S, Jung D, Kim K, Chae JA, Lim J, Park JW, Shin D, Char K, Jeong BG, Park JS, Hwang E, Lee DC, Park YS, Song HJ, Chang JH, Bae WK. Coherent heteroepitaxial growth of I-III-VI 2 Ag(In,Ga)S 2 colloidal nanocrystals with near-unity quantum yield for use in luminescent solar concentrators. Nat Commun 2023; 14:3779. [PMID: 37355655 DOI: 10.1038/s41467-023-39509-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 06/14/2023] [Indexed: 06/26/2023] Open
Abstract
Colloidal Ag(In,Ga)S2 nanocrystals (AIGS NCs) with the band gap tunability by their size and composition within visible range have garnered surging interest. High absorption cross-section and narrow emission linewidth of AIGS NCs make them ideally suited to address the challenges of Cd-free NCs in wide-ranging photonic applications. However, AIGS NCs have shown relatively underwhelming photoluminescence quantum yield (PL QY) to date, primarily because coherent heteroepitaxy has not been realized. Here, we report the heteroepitaxy for AIGS-AgGaS2 (AIGS-AGS) core-shell NCs bearing near-unity PL QYs in almost full visible range (460 to 620 nm) and enhanced photochemical stability. Key to the successful growth of AIGS-AGS NCs is the use of the Ag-S-Ga(OA)2 complex, which complements the reactivities among cations for both homogeneous AIGS cores in various compositions and uniform AGS shell growth. The heteroepitaxy between AIGS and AGS results in the Type I heterojunction that effectively confines charge carriers within the emissive core without optically active interfacial defects. AIGS-AGS NCs show higher extinction coefficient and narrower spectral linewidth compared to state-of-the-art heavy metal-free NCs, prompting their immediate use in practicable applications including displays and luminescent solar concentrators (LSCs).
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Affiliation(s)
- Hak June Lee
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
- School of Chemical and Biological Engineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Seongbin Im
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Dongju Jung
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Kyuri Kim
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Jong Ah Chae
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Jaemin Lim
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Jeong Woo Park
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Doyoon Shin
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Kookheon Char
- School of Chemical and Biological Engineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Byeong Guk Jeong
- School of Chemical and Biomolecular Engineering, Pusan National University, Busan, 46241, Republic of Korea
| | - Ji-Sang Park
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Euyheon Hwang
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Doh C Lee
- Department of Chemical and Biomolecular Engineering, KAIST Institute for the Nanocentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Young-Shin Park
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Hyung-Jun Song
- Department of Safety Engineering, Seoul National University of Science and Technology, Seoul, 01811, Republic of Korea.
| | - Jun Hyuk Chang
- Department of Chemistry, James Franck Institute, and Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, 60637, USA.
| | - Wan Ki Bae
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea.
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26
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Tang X, He S, Deng Y, Lu X, Zhu X, Jin W, Jin Y. Mg-Diffusion of ZnO-Based Electron-Transport Layers for Highly Conductive Quantum-Dot Light-Emitting Diodes. J Phys Chem Lett 2023:5812-5817. [PMID: 37338303 DOI: 10.1021/acs.jpclett.3c01465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/21/2023]
Abstract
Quantum-dot light-emitting diodes (QLEDs) show great potential in next-generation display and lighting technologies. Further reducing the resistances of the high-efficiency QLEDs is critical to improving their luminous efficiencies and lowering their power consumption. However, wet-chemistry methods to improve the conductivities of ZnO-based electron-transport layers (ETLs) often lead to trade-offs in the external quantum efficiencies (EQEs) of QLEDs. Here, we report a facile approach toward highly conductive QLEDs by in situ diffusion of Mg atoms into the ZnO-based ETLs. We demonstrate that thermally evaporated Mg can spread deep into the ZnO-based ETL with a long penetration length, generating oxygen vacancies that promote the electron-transport properties. The Mg-diffused ETLs enhance the conductivities and luminous efficiencies of state-of-the-art QLEDs without sacrificing the EQEs. This strategy is applied to QLEDs with various optical architectures, leading to significant enhancements in the current densities, luminances, and luminous efficiencies. We expect that our method could be extended to other solution-processed LEDs using ZnO-based ETLs.
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Affiliation(s)
- Xiaoqi Tang
- Key Laboratory of Excited-State Materials of Zhejiang Province, State Key Laboratory of Silicon and Advanced Semiconductor Materials, Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Siyu He
- Key Laboratory of Excited-State Materials of Zhejiang Province, State Key Laboratory of Silicon and Advanced Semiconductor Materials, Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Yunzhou Deng
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, International Research Center for Advanced Photonics, Zhejiang University, 310027, Hangzhou, China
- Cavendish Laboratory, University of Cambridge, CB3 0HE, Cambridge, United Kingdom
| | - Xiuyuan Lu
- Key Laboratory of Excited-State Materials of Zhejiang Province, State Key Laboratory of Silicon and Advanced Semiconductor Materials, Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Xitong Zhu
- Key Laboratory of Excited-State Materials of Zhejiang Province, State Key Laboratory of Silicon and Advanced Semiconductor Materials, Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Wangxiao Jin
- Key Laboratory of Excited-State Materials of Zhejiang Province, State Key Laboratory of Silicon and Advanced Semiconductor Materials, Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Yizheng Jin
- Key Laboratory of Excited-State Materials of Zhejiang Province, State Key Laboratory of Silicon and Advanced Semiconductor Materials, Department of Chemistry, Zhejiang University, Hangzhou 310027, China
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27
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Nguyen HA, Dixon G, Dou FY, Gallagher S, Gibbs S, Ladd DM, Marino E, Ondry JC, Shanahan JP, Vasileiadou ES, Barlow S, Gamelin DR, Ginger DS, Jonas DM, Kanatzidis MG, Marder SR, Morton D, Murray CB, Owen JS, Talapin DV, Toney MF, Cossairt BM. Design Rules for Obtaining Narrow Luminescence from Semiconductors Made in Solution. Chem Rev 2023. [PMID: 37311205 DOI: 10.1021/acs.chemrev.3c00097] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Solution-processed semiconductors are in demand for present and next-generation optoelectronic technologies ranging from displays to quantum light sources because of their scalability and ease of integration into devices with diverse form factors. One of the central requirements for semiconductors used in these applications is a narrow photoluminescence (PL) line width. Narrow emission line widths are needed to ensure both color and single-photon purity, raising the question of what design rules are needed to obtain narrow emission from semiconductors made in solution. In this review, we first examine the requirements for colloidal emitters for a variety of applications including light-emitting diodes, photodetectors, lasers, and quantum information science. Next, we will delve into the sources of spectral broadening, including "homogeneous" broadening from dynamical broadening mechanisms in single-particle spectra, heterogeneous broadening from static structural differences in ensemble spectra, and spectral diffusion. Then, we compare the current state of the art in terms of emission line width for a variety of colloidal materials including II-VI quantum dots (QDs) and nanoplatelets, III-V QDs, alloyed QDs, metal-halide perovskites including nanocrystals and 2D structures, doped nanocrystals, and, finally, as a point of comparison, organic molecules. We end with some conclusions and connections, including an outline of promising paths forward.
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Affiliation(s)
- Hao A Nguyen
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
| | - Grant Dixon
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
| | - Florence Y Dou
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
| | - Shaun Gallagher
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
| | - Stephen Gibbs
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
| | - Dylan M Ladd
- Department of Materials Science and Engineering, University of Colorado Boulder, Boulder, Colorado 80303, United States
| | - Emanuele Marino
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
- Dipartimento di Fisica e Chimica, Università degli Studi di Palermo, Via Archirafi 36, 90123 Palermo, Italy
| | - Justin C Ondry
- Department of Chemistry, James Franck Institute, and Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
| | - James P Shanahan
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Eugenia S Vasileiadou
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Stephen Barlow
- Renewable and Sustainable Energy Institute, University of Colorado Boulder, Boulder, Colorado 80303, United States
| | - Daniel R Gamelin
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
| | - David S Ginger
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
| | - David M Jonas
- Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States
- Renewable and Sustainable Energy Institute, University of Colorado Boulder, Boulder, Colorado 80303, United States
| | - Mercouri G Kanatzidis
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Seth R Marder
- Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States
- Renewable and Sustainable Energy Institute, University of Colorado Boulder, Boulder, Colorado 80303, United States
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80303, United States
| | - Daniel Morton
- Renewable and Sustainable Energy Institute, University of Colorado Boulder, Boulder, Colorado 80303, United States
| | - Christopher B Murray
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Jonathan S Owen
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Dmitri V Talapin
- Department of Chemistry, James Franck Institute, and Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
| | - Michael F Toney
- Department of Materials Science and Engineering, University of Colorado Boulder, Boulder, Colorado 80303, United States
- Renewable and Sustainable Energy Institute, University of Colorado Boulder, Boulder, Colorado 80303, United States
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80303, United States
| | - Brandi M Cossairt
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
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28
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Gunnarsson WB, Roh K, Zhao L, Murphy JP, Grede AJ, Giebink NC, Rand BP. Toward Nonepitaxial Laser Diodes. Chem Rev 2023. [PMID: 37219995 DOI: 10.1021/acs.chemrev.2c00721] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Thin-film organic, colloidal quantum dot, and metal halide perovskite semiconductors are all being pursued in the quest for a wavelength-tunable diode laser technology that does not require epitaxial growth on a traditional semiconductor substrate. Despite promising demonstrations of efficient light-emitting diodes and low-threshold optically pumped lasing in each case, there are still fundamental and practical barriers that must be overcome to reliably achieve injection lasing. This review outlines the historical development and recent advances of each material system on the path to a diode laser. Common challenges in resonator design, electrical injection, and heat dissipation are highlighted, as well as the different optical gain physics that make each system unique. The evidence to date suggests that continued progress for organic and colloidal quantum dot laser diodes will likely hinge on the development of new materials or indirect pumping schemes, while improvements in device architecture and film processing are most critical for perovskite lasers. In all cases, systematic progress will require methods that can quantify how close new devices get with respect to their electrical lasing thresholds. We conclude by discussing the current status of nonepitaxial laser diodes in the historical context of their epitaxial counterparts, which suggests that there is reason to be optimistic for the future.
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Affiliation(s)
- William B Gunnarsson
- Department of Electrical and Computer Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Kwangdong Roh
- Department of Physics, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Lianfeng Zhao
- Holcombe Department of Electrical and Computer Engineering, Clemson University, Clemson, South Carolina 29634, United States
| | - John P Murphy
- Department of Electrical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Alex J Grede
- Department of Electrical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Noel C Giebink
- Department of Electrical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Barry P Rand
- Department of Electrical and Computer Engineering, Princeton University, Princeton, New Jersey 08544, United States
- Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544, United States
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29
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Huang Z, Sun Q, Wang S, Shen H, Cai W, Wang Y. Broadband Tunable Optical Gain from Ecofriendly Semiconductor Quantum Dots with Near-Half-Exciton Threshold. NANO LETTERS 2023; 23:4032-4038. [PMID: 37125767 DOI: 10.1021/acs.nanolett.3c00813] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Optical gain in solution-processable quantum dots (QDs) has attracted intense interest toward next-generation optoelectronics; however, the development of optical gain in heavy-metal-free QDs remains challenging. Herein, we reveal that the ZnSe1-xTex-based QDs show excellent optical gain covering the violet to near-red regime. A new gain mechanism is established in the alloy QDs, which promotes a theoretically threshold-less optical gain thanks to the ultrafast carrier localization and suppression of ground-state absorption by the Te-derived isoelectronic state. Further, we disclose that the hot-carrier trapping represents the main culprit to exacerbate the gain performance. With the increase of Te-to-Se ratio, a sub-band-gap photoinduced absorption (PA) appears and extinguishes the optical gain. To overcome this issue, we modulate the inner ZnSe shell thickness, and the gain is recovered by reducing the overlap between the gain and PA regions in the Te-rich QDs. Our finding represents a significant step toward sustainable QD-based optoelectronics.
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Affiliation(s)
- Zhigao Huang
- MIIT Key Laboratory of Advanced Display Materials and Devices, College of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Qi Sun
- MIIT Key Laboratory of Advanced Display Materials and Devices, College of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Sensen Wang
- MIIT Key Laboratory of Advanced Display Materials and Devices, College of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Hanchen Shen
- MIIT Key Laboratory of Advanced Display Materials and Devices, College of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Wenbing Cai
- MIIT Key Laboratory of Advanced Display Materials and Devices, College of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Yue Wang
- MIIT Key Laboratory of Advanced Display Materials and Devices, College of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
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30
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Azadinia M, Davidson-Hall T, Chung DS, Ghorbani A, Samaeifar F, Chen J, Chun P, Lyu Q, Cotella G, Aziz H. Inverted Solution-Processed Quantum Dot Light-Emitting Devices with Wide Band Gap Quantum Dot Interlayers. ACS APPLIED MATERIALS & INTERFACES 2023; 15:23631-23641. [PMID: 37141421 DOI: 10.1021/acsami.3c02356] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Despite its benefits for facilitating device fabrication, utilization of a polymeric hole transport layer (HTL) in inverted quantum dots (QDs) light-emitting devices (IQLEDs) often leads to poor device performance. In this work, we find that the poor performance arises primarily from electron leakage, inefficient charge injection, and significant exciton quenching at the HTL interface in the inverted architecture and not due to solvent damage effects as is widely believed. We also find that using a layer of wider band gap QDs as an interlayer (IL) in between the HTL and the main QDs' emission material layer (EML) can facilitate hole injection, suppress electron leakage, and reduce exciton quenching, effectively mitigating the poor interface effects and resulting in high electroluminescence performance. Using an IL in IQLEDs with a solution-processed poly(9,9-dioctylfluorene-alt-N-(4-sec-butylphenyl)-diphenylamine) (TFB), HTL improves the efficiency by 2.85× (from 3 to 8.56%) and prolongs the lifetime by 9.4× (from 1266 to 11,950 h at 100 cd/m2), which, to the best of our knowledge, is the longest lifetime for an R-IQLED with a solution-coated HTL. Measurements on single-carrier devices reveal that while electron injection becomes easier as the band gap of the QDs decreases, hole injection surprisingly becomes more difficult, indicating that EMLs of QLEDs are more electron-rich in the case of red devices and more hole-rich in the case of blue devices. Ultraviolet photoelectron spectroscopy measurements verify that blue QDs have a shallower valence band energy than their red counterparts, corroborating these conclusions. The findings in this work, therefore, provide not only a simple approach for achieving high performance in IQLEDs with solution-coated HTLs but also novel insights into charge injection and its dependence on QDs' band gap as well as into different HTL interface properties of the inverted versus upright architecture.
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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
| | - Tyler Davidson-Hall
- Department of Electrical and Computer Engineering and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada
| | - Dong Seob Chung
- Department of Electrical and Computer Engineering and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada
| | - 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
| | - Fatemeh Samaeifar
- 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
| | - Peter Chun
- Ottawa IC Laboratory, Huawei Canada, 19 Allstate Parkway, Markham, Ontario L3R 5B4, Canada
| | - Quan Lyu
- Cambridge Research Centre, Huawei Technologies Research & Development (UK) Ltd., Cambridge CB4 0FY, U.K
| | - Giovanni Cotella
- Ipswich Research Centre, Huawei Technologies Research & Development (UK) 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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31
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Ahn N, Livache C, Pinchetti V, Jung H, Jin H, Hahm D, Park YS, Klimov VI. Electrically driven amplified spontaneous emission from colloidal quantum dots. Nature 2023; 617:79-85. [PMID: 37138110 PMCID: PMC10156592 DOI: 10.1038/s41586-023-05855-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 02/16/2023] [Indexed: 05/05/2023]
Abstract
Colloidal quantum dots (QDs) are attractive materials for realizing solution-processable laser diodes that could benefit from size-controlled emission wavelengths, low optical-gain thresholds and ease of integration with photonic and electronic circuits1-7. However, the implementation of such devices has been hampered by fast Auger recombination of gain-active multicarrier states1,8, poor stability of QD films at high current densities9,10 and the difficulty to obtain net optical gain in a complex device stack wherein a thin electroluminescent QD layer is combined with optically lossy charge-conducting layers11-13. Here we resolve these challenges and achieve amplified spontaneous emission (ASE) from electrically pumped colloidal QDs. The developed devices use compact, continuously graded QDs with suppressed Auger recombination incorporated into a pulsed, high-current-density charge-injection structure supplemented by a low-loss photonic waveguide. These colloidal QD ASE diodes exhibit strong, broadband optical gain and demonstrate bright edge emission with instantaneous power of up to 170 μW.
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Affiliation(s)
- Namyoung Ahn
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Clément Livache
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Valerio Pinchetti
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Heeyoung Jung
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, USA
- Center for High Technology Materials, University of New Mexico, Albuquerque, NM, USA
| | - Ho Jin
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, USA
- Center for High Technology Materials, University of New Mexico, Albuquerque, NM, USA
| | - Donghyo Hahm
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Young-Shin Park
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Victor I Klimov
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, USA.
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32
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Liu L, Bai B, Yang X, Du Z, Jia G. Anisotropic Heavy-Metal-Free Semiconductor Nanocrystals: Synthesis, Properties, and Applications. Chem Rev 2023; 123:3625-3692. [PMID: 36946890 DOI: 10.1021/acs.chemrev.2c00688] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023]
Abstract
Heavy-metal (Cd, Hg, and Pb)-containing semiconductor nanocrystals (NCs) have been explored widely due to their unique optical and electrical properties. However, the toxicity risks of heavy metals can be a drawback of heavy-metal-containing NCs in some applications. Anisotropic heavy-metal-free semiconductor NCs are desirable replacements and can be realized following the establishment of anisotropic growth mechanisms. These anisotropic heavy-metal-free semiconductor NCs can possess lower toxicity risks, while still exhibiting unique optical and electrical properties originating from both the morphological and compositional anisotropy. As a result, they are promising light-emitting materials in use various applications. In this review, we provide an overview on the syntheses, properties, and applications of anisotropic heavy-metal-free semiconductor NCs. In the first section, we discuss hazards of heavy metals and introduce the typical heavy-metal-containing and heavy-metal-free NCs. In the next section, we discuss anisotropic growth mechanisms, including solution-liquid-solid (SLS), oriented attachment, ripening, templated-assisted growth, and others. We discuss mechanisms leading both to morphological anisotropy and to compositional anisotropy. Examples of morphological anisotropy include growth of nanorods (NRs)/nanowires (NWs), nanotubes, nanoplatelets (NPLs)/nanosheets, nanocubes, and branched structures. Examples of compositional anisotropy, including heterostructures and core/shell structures, are summarized. Third, we provide insights into the properties of anisotropic heavy-metal-free NCs including optical polarization, fast electron transfer, localized surface plasmon resonances (LSPR), and so on, which originate from the NCs' anisotropic morphologies and compositions. Finally, we summarize some applications of anisotropic heavy-metal-free NCs including catalysis, solar cells, photodetectors, lighting-emitting diodes (LEDs), and biological applications. Despite the huge progress on the syntheses and applications of anisotropic heavy-metal-free NCs, some issues still exist in the novel anisotropic heavy-metal-free NCs and the corresponding energy conversion applications. Therefore, we also discuss the challenges of this field and provide possible solutions to tackle these challenges in the future.
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Affiliation(s)
- Long Liu
- Key Lab for Special Functional Materials, Ministry of Education, National and Local Joint Engineering Research Center for High-Efficiency Display and Lighting Technology, School of Materials Science and Engineering, and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, China
| | - Bing Bai
- Key Lab for Special Functional Materials, Ministry of Education, National and Local Joint Engineering Research Center for High-Efficiency Display and Lighting Technology, School of Materials Science and Engineering, and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, China
| | - Xuyong Yang
- Key Laboratory of Advanced Display and System Applications of Ministry of Education, Shanghai University, 149 Yanchang Road, Shanghai 200072, P. R. China
| | - Zuliang Du
- Key Lab for Special Functional Materials, Ministry of Education, National and Local Joint Engineering Research Center for High-Efficiency Display and Lighting Technology, School of Materials Science and Engineering, and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, China
| | - Guohua Jia
- School of Molecular and Life Sciences, Curtin University, Perth, WA 6102, Australia
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33
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Ahn N, Park YS, Livache C, Du J, Gungor K, Kim J, Klimov VI. Optically Excited Lasing in a Cavity-Based, High-Current-Density Quantum Dot Electroluminescent Device. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2206613. [PMID: 36528387 DOI: 10.1002/adma.202206613] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 10/31/2022] [Indexed: 06/17/2023]
Abstract
Laser diodes based on solution-processable materials can benefit numerous technologies including integrated electronics and photonics, telecommunications, and medical diagnostics. An attractive system for implementing these devices is colloidal semiconductor quantum dots (QDs). The progress towards a QD laser diode has been hampered by rapid nonradiative Auger decay of optical-gain-active multicarrier states, fast device degradation at high current densities required for laser action, and unfavorable competition between optical gain and optical losses in a multicomponent device stack. Here we resolve some of these challenges and demonstrate optically excited lasing from fully functional high-current density electroluminescent (EL) devices with an integrated optical resonator. This advance has become possible due to excellent optical gain properties of continuously graded QDs and a refined device architecture, which allows for highly efficient light amplification in a thin, EL-active QD layer.
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Affiliation(s)
- Namyoung Ahn
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Young-Shin Park
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Clément Livache
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Jun Du
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, China
| | - Kivanc Gungor
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Jaehoon Kim
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Victor I Klimov
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
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34
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Neuhaus SJ, Marino E, Murray CB, Kagan CR. Frequency Stabilization and Optically Tunable Lasing in Colloidal Quantum Dot Superparticles. NANO LETTERS 2023; 23:645-651. [PMID: 36602545 DOI: 10.1021/acs.nanolett.2c04498] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Self-assembled superparticles composed of colloidal quantum dots establish microsphere cavities that support optically pumped lasing from whispering gallery modes. Here, we report on the time- and excitation fluence-dependent lasing properties of CdSe/CdS quantum dot superparticles. Spectra collected under constant photoexcitation reveal that the lasing modes are not temporally stable but instead blue-shift by more than 30 meV over 15 min. To counter this effect, we establish a high-fluence light-soaking protocol that reduces this blue-shift by more than an order of magnitude to 1.7 ± 0.5 meV, with champion superparticles displaying mode blue-shifts of <0.5 meV. Increasing the pump fluence allows for optically controlled, reversible, color-tunable red-to-green lasing. Combining these two paradigms suggests that quantum dot superparticles could serve in applications as low-cost, robust, solution-processable, tunable microlasers.
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Affiliation(s)
- Steven J Neuhaus
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania19104, United States
| | - Emanuele Marino
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania19104, United States
- Dipartimento di Fisica e Chimica, Università degli Studi di Palermo, Via Archirafi 36, 90123Palermo, Italy
| | - Christopher B Murray
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania19104, United States
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania19104, United States
| | - Cherie R Kagan
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania19104, United States
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania19104, United States
- Department of Electrical and System Engineering, University of Pennsylvania, Philadelphia, Pennsylvania19104, United States
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35
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Heteroepitaxial chemistry of zinc chalcogenides on InP nanocrystals for defect-free interfaces with atomic uniformity. Nat Commun 2023; 14:43. [PMID: 36596807 PMCID: PMC9810615 DOI: 10.1038/s41467-022-35731-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 12/19/2022] [Indexed: 01/05/2023] Open
Abstract
Heteroepitaxy on colloidal semiconductor nanocrystals is an essential strategy for manipulating their optoelectronic functionalities. However, their practical synthesis typically leads to scattered and unexpected outcomes due to the intervention of multiple reaction pathways associated with complicated side products of reactants. Here, the heteroepitaxy mechanism of zinc chalcogenide initiated on indium phosphide (InP) colloidal nanocrystals is elucidated using the precursors, zinc carboxylate and trialkylphosphine selenide. The high magnetic receptivity of 77Se and the characteristic longitudinal optical phonon mode of ZnSe allowed for monitoring the sequence of epilayer formation at the molecular level. The investigation revealed the sterically hindered acyloxytrialkylphosphonium and diacyloxytrialkylphosphorane to be main intermediates in the surface reaction, which retards the metal ion adsorption by a large steric hindrance. The transformation of adsorbates to the crystalline epilayer was disturbed by surface oxides. Raman scattering disclosed the pathway of secondary surface oxidation triggered by carboxylate ligands migrated from zinc carboxylate. The surface-initiated heteroepitaxy protocol is proposed to fabricate core/shell heterostructured nanocrystals with atomic-scale uniformity of epilayers. Despite the large lattice mismatch of ZnS to InP, we realised a uniform and interface defect-free ZnS epilayer (~0.3 nm thickness) on InP nanocrystals, as evidenced by a high photoluminescence quantum yield of 97.3%.
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36
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Taghipour N, Dalmases M, Whitworth GL, Dosil M, Othonos A, Christodoulou S, Liga SM, Konstantatos G. Colloidal Quantum Dot Infrared Lasers Featuring Sub-Single-Exciton Threshold and Very High Gain. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2207678. [PMID: 36333885 DOI: 10.1002/adma.202207678] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 10/22/2022] [Indexed: 06/16/2023]
Abstract
The use of colloidal quantum dots (CQDs) as a gain medium in infrared laser devices has been underpinned by the need for high pumping intensities, very short gain lifetimes, and low gain coefficients. Here, PbS/PbSSe core/alloyed-shell CQDs are employed as an infrared gain medium that results in highly suppressed Auger recombination with a lifetime of 485 ps, lowering the amplified spontaneous emission (ASE) threshold down to 300 µJ cm-2 , and showing a record high net modal gain coefficient of 2180 cm-1 . By doping these engineered core/shell CQDs up to nearly filling the first excited state, a significant reduction of optical gain threshold is demonstrated, measured by transient absorption, to an average-exciton population-per-dot 〈Nth 〉g of 0.45 due to bleaching of the ground state absorption. This in turn have led to a fivefold reduction in ASE threshold at 〈Nth 〉ASE = 0.70 excitons-per-dot, associated with a gain lifetime of 280 ps. Finally, these heterostructured QDs are used to achieve near-infrared lasing at 1670 nm at a pump fluences corresponding to sub-single-exciton-per-dot threshold (〈Nth 〉Las = 0.87). This work brings infrared CQD lasing thresholds on par to their visible counterparts, and paves the way toward solution-processed infrared laser diodes.
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Affiliation(s)
- Nima Taghipour
- ICFO, Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, 08860, Spain
| | - Mariona Dalmases
- ICFO, Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, 08860, Spain
| | - Guy L Whitworth
- ICFO, Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, 08860, Spain
| | - Miguel Dosil
- ICFO, Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, 08860, Spain
| | - Andreas Othonos
- Laboratory of Ultrafast Science, Department of Physics, University of Cyprus, Nicosia, 1678, Cyprus
| | - Sotirios Christodoulou
- Inorganic Nanocrystals Laboratory, Department of Chemistry, University of Cyprus, Nicosia, 1678, Cyprus
| | - Shanti Maria Liga
- ICFO, Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, 08860, Spain
| | - Gerasimos Konstantatos
- ICFO, Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, 08860, Spain
- ICREA, Institució Catalana de Recerca i Estudis Avançats, Barcelona, 08010, Spain
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37
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Chang JH, Jung D, Lee HJ, Shin D, Kim Y, Hahm D, Wang X, Lee DC, Hwang E, Park YS, Bae WK. Impact of Morphological Inhomogeneity on Excitonic States in Highly Mismatched Alloy ZnSe 1-XTe X Nanocrystals. J Phys Chem Lett 2022; 13:11464-11472. [PMID: 36469328 DOI: 10.1021/acs.jpclett.2c03050] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
ZnSe1-XTeX nanocrystals (NCs) are promising photon emitters with tunable emission across the violet to orange range and near-unity quantum yields. However, these NCs suffer from broad emission line widths and multiple exciton decay dynamics, which discourage their practicable use. Here, we explore the excitonic states in ZnSe1-XTeX NCs and their photophysical characteristics in relation to the morphological inhomogeneity of highly mismatched alloys. Ensemble and single-dot spectroscopic analysis of a series of ZnSe1-XTeX NC samples with varying Te ratios coupled with computational calculations shows that, due to the distinct electronegativity between Se and Te, nearest-neighbor Te pairs in ZnSe1-XTeX alloys create localized hole states spectrally distributed approximately 130 meV above the 1Sh level of homogeneous ZnSe1-XTeX NCs. This forms spatially separated excitons (delocalized electron and localized hole in trap), accounting for both inhomogeneous and homogeneous line width broadening with delayed recombination dynamics. Our results identify photophysical characteristics of excitonic states in NCs made of highly mismatched alloys and provide future research directions with potential implications for photonic applications.
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Affiliation(s)
- Jun Hyuk Chang
- SKKU Advanced Institute of Nano Technology, Sungkyunkwan University, Suwon 16419, Korea
| | - Dongju Jung
- SKKU Advanced Institute of Nano Technology, Sungkyunkwan University, Suwon 16419, Korea
| | - Hak June Lee
- School of Chemical and Biological Engineering, Seoul National University, Seoul 08826, Korea
| | - Doyoon Shin
- SKKU Advanced Institute of Nano Technology, Sungkyunkwan University, Suwon 16419, Korea
| | - Youngdu Kim
- SKKU Advanced Institute of Nano Technology, Sungkyunkwan University, Suwon 16419, Korea
| | - Donghyo Hahm
- SKKU Advanced Institute of Nano Technology, Sungkyunkwan University, Suwon 16419, Korea
| | - Xinbiao Wang
- SKKU Advanced Institute of Nano Technology, Sungkyunkwan University, Suwon 16419, Korea
| | - Doh C Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Euyheon Hwang
- SKKU Advanced Institute of Nano Technology, Sungkyunkwan University, Suwon 16419, Korea
| | - Young-Shin Park
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Wan Ki Bae
- SKKU Advanced Institute of Nano Technology, Sungkyunkwan University, Suwon 16419, Korea
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38
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Bera SK, Bera S, Shrivastava M, Pradhan N, Adarsh KV. Facet Engineering for Amplified Spontaneous Emission in Metal Halide Perovskite Nanocrystals. NANO LETTERS 2022; 22:8908-8916. [PMID: 36318695 DOI: 10.1021/acs.nanolett.2c02982] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Auger recombination and thermalization time are detrimental in reducing the gain threshold of optically pumped semiconductor nanocrystal (NC) lasers for future on-chip nanophotonic devices. Here, we report the design strategy of facet engineering to reduce the gain threshold of amplified spontaneous emission by manyfold in NCs of the same concentration and edge length. We achieved this hallmark result by controlling the Auger recombination rates dominated by processes involving NC volume and thermalization time to the emitting states by optimizing the number of facets from 6 (cube) to 12 (rhombic dodecahedron) and 26 (rhombicuboctahedrons) in CsPbBr3 NCs. For instance, we demonstrate a 2-fold reduction in Auger recombination rates and thermalization time with increased number of facets. The gain threshold can be further reduced ∼50% by decreasing the sample temperature to 4 K. Our systematic studies offer a new method to reduce the gain threshold that ultimately forms the basis of nanolasers.
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Affiliation(s)
- Santu K Bera
- Department of Physics, Indian Institute of Science Education and Research, Bhopal462066, India
| | - Suman Bera
- School of Materials Sciences, Indian Association for the Cultivation of Science, Kolkata700032, India
| | - Megha Shrivastava
- Department of Physics, Indian Institute of Science Education and Research, Bhopal462066, India
| | - Narayan Pradhan
- School of Materials Sciences, Indian Association for the Cultivation of Science, Kolkata700032, India
| | - K V Adarsh
- Department of Physics, Indian Institute of Science Education and Research, Bhopal462066, India
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39
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Geuchies JJ, Dijkhuizen R, Koel M, Grimaldi G, du Fossé I, Evers WH, Hens Z, Houtepen AJ. Zero-Threshold Optical Gain in Electrochemically Doped Nanoplatelets and the Physics Behind It. ACS NANO 2022; 16:18777-18788. [PMID: 36256901 PMCID: PMC9706803 DOI: 10.1021/acsnano.2c07519] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 10/13/2022] [Indexed: 06/07/2023]
Abstract
Colloidal nanoplatelets (NPLs) are promising materials for lasing applications. The properties are usually discussed in the framework of 2D materials, where strong excitonic effects dominate the optical properties near the band edge. At the same time, NPLs have finite lateral dimensions such that NPLs are not true extended 2D structures. Here we study the photophysics and gain properties of CdSe/CdS/ZnS core-shell-shell NPLs upon electrochemical n doping and optical excitation. Steady-state absorption and PL spectroscopy show that excitonic effects are weaker in core-shell-shell nanoplatelets due to the decreased exciton binding energy. Transient absorption studies reveal a gain threshold of only one excitation per nanoplatelet. Using electrochemical n doping, we observe the complete bleaching of the band edge exciton transitions. Combining electrochemical doping with transient absorption spectroscopy, we demonstrate that the gain threshold is fully removed over a broad spectral range and gain coefficients of several thousand cm-1 are obtained. These doped NPLs are the best performing colloidal nanomaterial gain medium reported to date, with the lowest gain threshold and broadest gain spectrum and gain coefficients that are 4 times higher than in n-doped colloidal quantum dots. The low exciton binding energy due to the CdS and ZnS shells, in combination with the relatively small lateral size of the NPLs, results in excited states that are effectively delocalized over the entire platelet. Core-shell NPLs are thus on the border between strong confinement in QDs and dominant Coulombic effects in 2D materials. We demonstrate that this limit is in effect ideal for optical gain and that it results in an optimal lateral size of the platelets where the gain threshold per nm2 is minimal.
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Affiliation(s)
- Jaco J. Geuchies
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2926 HZDelft, The Netherlands
| | - Robbert Dijkhuizen
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2926 HZDelft, The Netherlands
| | - Marijn Koel
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2926 HZDelft, The Netherlands
| | - Gianluca Grimaldi
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2926 HZDelft, The Netherlands
| | - Indy du Fossé
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2926 HZDelft, The Netherlands
| | - Wiel H. Evers
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2926 HZDelft, The Netherlands
| | - Zeger Hens
- Department
of Chemistry and Center for Nano and Biophotonics, Ghent University, 9000Ghent, Belgium
| | - Arjan J. Houtepen
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2926 HZDelft, The Netherlands
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40
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Chung DS, Davidson-Hall T, Cotella G, Lyu Q, Chun P, Aziz H. Significant Lifetime Enhancement in QLEDs by Reducing Interfacial Charge Accumulation via Fluorine Incorporation in the ZnO Electron Transport Layer. NANO-MICRO LETTERS 2022; 14:212. [PMID: 36333462 PMCID: PMC9636368 DOI: 10.1007/s40820-022-00970-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 10/08/2022] [Indexed: 05/22/2023]
Abstract
ZnO nanoparticles are widely used for the electron transport layers (ETLs) of quantum dots light emitting devices (QLEDs). In this work we show that incorporating fluorine (F) into the ZnO ETL results in significant enhancement in device electroluminescence stability, leading to LT50 at 100 cd m-2 of 2,370,000 h in red QLED, 47X longer than the control devices. X-ray photo-electron spectroscopy, time-of-flight secondary ion mass spectroscopy, photoluminescence and electrical measurements show that the F passivates oxygen vacancies and reduces electron traps in ZnO. Transient photoluminescence versus bias measurements and capacitance-voltage-luminance measurements reveal that the CF4 plasma-treated ETLs lead to increased electron concentration in the QD and the QD/hole transport layer interface, subsequently decreasing hole accumulation, and hence the higher stability. The findings provide new insights into the critical roles that optimizing charge distribution across the layers play in influencing stability and present a novel and simple approach for extending QLED lifetimes.
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Affiliation(s)
- Dong Seob Chung
- Department of Electrical and Computer Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1, Canada.
| | - Tyler Davidson-Hall
- Department of Electrical and Computer Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1, Canada
| | - Giovanni Cotella
- Ipswich Research Centre, Huawei Technologies Research & Development (UK) Ltd., Phoenix House (B55), Adastral Park, Ipswich, IP5 3RE, UK
| | - Quan Lyu
- Ipswich Research Centre, Huawei Technologies Research & Development (UK) Ltd., Phoenix House (B55), Adastral Park, Ipswich, IP5 3RE, UK
| | - Peter Chun
- Ottawa IC Laboratory, Huawei Canada, 19 Allstate Parkway, Markham, ON, L3R 5B4, Canada
| | - Hany Aziz
- Department of Electrical and Computer Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1, Canada.
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41
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Belitsch M, Dirin DN, Kovalenko MV, Pichler K, Rotter S, Ghalgaoui A, Ditlbacher H, Hohenau A, Krenn JR. Gain and lasing from CdSe/CdS nanoplatelet stripe waveguides. MICRO AND NANO ENGINEERING 2022. [DOI: 10.1016/j.mne.2022.100167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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42
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Gréboval C, Darson D, Parahyba V, Alchaar R, Abadie C, Noguier V, Ferré S, Izquierdo E, Khalili A, Prado Y, Potet P, Lhuillier E. Photoconductive focal plane array based on HgTe quantum dots for fast and cost-effective short-wave infrared imaging. NANOSCALE 2022; 14:9359-9368. [PMID: 35726871 DOI: 10.1039/d2nr01313d] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
HgTe nanocrystals, thanks to quantum confinement, present a broadly tunable band gap all over the infrared spectral range. In addition, significant efforts have been dedicated to the design of infrared sensors with an absorbing layer made of nanocrystals. However, most efforts have been focused on single pixel sensors. Nanocrystals offer an appealing alternative to epitaxially grown semiconductors for infrared imaging by reducing the material growth cost and easing the coupling to the readout circuit. Here we propose a strategy to design an infrared focal plane array from a single fabrication step. The focal plane array (FPA) relies on a specifically designed readout circuit enabling in plane electric field application and operation in photoconductive mode. We demonstrate a VGA format focal plane array with a 15 μm pixel pitch presenting an external quantum efficiency of 4-5% (15% internal quantum efficiency) for a cut-off around 1.8 μm and operation using Peltier cooling only. The FPA is compatible with 200 fps imaging full frame and imaging up to 340 fps is demonstrated by driving a reduced area of the FPA. In the last part of the paper, we discuss the cost of such sensors and show that the latter is only driven by labor costs while we estimate the cost of the NC film to be in the 10-20 € range.
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Affiliation(s)
- Charlie Gréboval
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France.
| | - David Darson
- Laboratoire de Physique de l'Ecole normale supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris-Diderot, Sorbonne Paris Cité, Paris, France
| | - Victor Parahyba
- New Imaging Technologies SA, 1 impasse de la Noisette, 91370 Verrières le Buisson, France
| | - Rodolphe Alchaar
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France.
| | - Claire Abadie
- ONERA - The French Aerospace Lab, 6, chemin de la Vauve aux Granges, BP 80100, 91123 Palaiseau, France
| | - Vincent Noguier
- New Imaging Technologies SA, 1 impasse de la Noisette, 91370 Verrières le Buisson, France
| | - Simon Ferré
- New Imaging Technologies SA, 1 impasse de la Noisette, 91370 Verrières le Buisson, France
| | - Eva Izquierdo
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France.
| | - Adrien Khalili
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France.
| | - Yoann Prado
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France.
| | - Pierre Potet
- New Imaging Technologies SA, 1 impasse de la Noisette, 91370 Verrières le Buisson, France
| | - Emmanuel Lhuillier
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France.
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43
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Kim J, Hahm D, Bae WK, Lee H, Kwak J. Transient Dynamics of Charges and Excitons in Quantum Dot Light-Emitting Diodes. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2202290. [PMID: 35754301 DOI: 10.1002/smll.202202290] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 05/28/2022] [Indexed: 06/15/2023]
Abstract
Wide interest in quantum dot (QD) light-emitting diodes (QLEDs) for potential application to display devices and light sources has led to their rapid advancement in device performance. Despite such progress, detailed operation mechanisms of QLEDs, which are necessary for the fundamental understanding and further improvements, have been still uncertain because of the intricate interaction between charges and excitons in electrical operation. In this work, the transient electroluminescence (TREL) signals of dichromatic QLEDs which are purposely designed to consist of two different color-emitting QD layers are analyzed. As a result, not only can the charge injection and exciton recombination processes be visualized but the electron mobility of the QD layer can also be estimated. Furthermore, the effects of Förster resonant energy transfer between two QDs and exciton quenching near the QD layer are quantitatively measured in QLED operation. The authors believe that their results based on TREL analyses will contribute to the understanding and development of high-performance QLEDs.
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Affiliation(s)
- Jaeyoul Kim
- Department of Electrical and Computer Engineering, Inter-university Semiconductor Research Center (ISRC), Seoul National University, Seoul, 08826, Republic of Korea
| | - Donghyo Hahm
- SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Wan Ki Bae
- SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Hyunho Lee
- Department of Electronic Engineering, Kwangwoon University, Seoul, 01897, Republic of Korea
| | - Jeonghun Kwak
- Department of Electrical and Computer Engineering, Inter-university Semiconductor Research Center (ISRC), Seoul National University, Seoul, 08826, Republic of Korea
- Soft Foundry Institute, Seoul National University, 1-Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
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44
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Jung H, Park YS, Ahn N, Lim J, Fedin I, Livache C, Klimov VI. Two-band optical gain and ultrabright electroluminescence from colloidal quantum dots at 1000 A cm -2. Nat Commun 2022; 13:3734. [PMID: 35768407 PMCID: PMC9243032 DOI: 10.1038/s41467-022-31189-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 06/08/2022] [Indexed: 11/09/2022] Open
Abstract
Colloidal quantum dots (QDs) are attractive materials for the realization of solution-processable laser diodes. Primary challenges towards this objective are fast optical-gain relaxation due to nonradiative Auger recombination and poor stability of colloidal QD solids under high current densities required to obtain optical gain. Here we resolve these challenges and achieve broad-band optical gain spanning the band-edge (1S) and the higher-energy (1P) transitions. This demonstration is enabled by continuously graded QDs with strongly suppressed Auger recombination and a current-focusing device design, combined with short-pulse pumping. Using this approach, we achieve ultra-high current densities (~1000 A cm−2) and brightness (~10 million cd m−2), and demonstrate an unusual two-band electroluminescence regime for which the 1P band is more intense than the 1S feature. This implies the realization of extremely large QD occupancies of up to ~8 excitons per-dot, which corresponds to complete filling of the 1S and 1P electron shells. Nonradiative Auger recombination and poor stability of colloidal-quantum-dot solids at high current densities are primary obstacles to the realization of laser diodes based on these materials. Jung et al. achieve the current densities in excess of 1,000 A cm−2, which allows them to boost brightness to ~10 million cd m−2 and to produce strong, two-band optical gain.
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Affiliation(s)
- Heeyoung Jung
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Young-Shin Park
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.,Centre for High Technology Materials, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Namyoung Ahn
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Jaehoon Lim
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.,Department of Energy Science and Centre for Artificial Atom, Sungkyunkwan University, Natural Sciences Campus, Seobu-ro 2066, Jangan-gu, Suwon, 16419, Gyeonggi-do, Republic of Korea
| | - Igor Fedin
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Clément Livache
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Victor I Klimov
- Nanotechnology and Advanced Spectroscopy Team, C-PCS, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.
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45
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Zhao Y, Feng J, Chen G, Wu JJ, Wang XD, Jiang L, Wu Y. Deterministic Assembly of Colloidal Quantum Dots for Multifunctional Integrated Photonics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2110695. [PMID: 35411618 DOI: 10.1002/adma.202110695] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 03/28/2022] [Indexed: 06/14/2023]
Abstract
Colloidal quantum dots (CQDs) are promising for photonic applications toward lasers, waveguides, and photodetectors. However, integration of high-quality photonic elements into multifunctional devices is still restricted by optical losses stemming from the accumulation of defects and disorder in the solution process. Herein, a platform with a directional Laplace pressure is created for eliminating undesired pinning of liquid fronts in the solution process and boosting ordered assembly of CQDs into designable micro-/nanostructures. The versatility and robustness of this method are demonstrated by deterministic patterning of CQDs with different components and photoluminescence spectra onto various substrates. On the basis of this platform, microring lasers with tunable emission modes, low-loss waveguides, and their coupled structures have been reached for direct on-chip generation and propagation of coherent light. A proof-of-concept demonstration of integrated circuits is also conducted by combining microcavity lasers with waveguides for encoding photonic outputs into information bits.
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Affiliation(s)
- Yuyan Zhao
- Key Laboratory of Bio-inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| | - Jiangang Feng
- Department of Chemical and Biomolecular Sciences, National University of Singapore, Singapore, 117585, Singapore
| | - Gaosong Chen
- School of Chemistry, Beihang University, Beijing, 100191, P. R. China
| | - Jun-Jie Wu
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Xue-Dong Wang
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Lei Jiang
- Key Laboratory of Bio-inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
- School of Chemistry, Beihang University, Beijing, 100191, P. R. China
| | - Yuchen Wu
- Key Laboratory of Bio-inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
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46
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Wang L, Bai J, Zhang T, Huang X, Hou T, Xu B, Li D, Li Q, Jin X, Wang Y, Zhang X, Song Y. Controlling the emission linewidths of alloy quantum dots with asymmetric strain. J Colloid Interface Sci 2022; 624:287-295. [DOI: 10.1016/j.jcis.2022.05.140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 05/12/2022] [Accepted: 05/23/2022] [Indexed: 11/16/2022]
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47
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Yang Z, Ma P, Bai G, Sun B, Du W, Wang T. Microcavity coupled quantum dot emission with detuning control. OPTICS LETTERS 2022; 47:2089-2092. [PMID: 35427344 DOI: 10.1364/ol.456995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 03/22/2022] [Indexed: 06/14/2023]
Abstract
Solution processed colloidal semiconductor quantum dots (QDs) have size-tunable optical transitions and high quantum efficiencies, enabling various applications in opto-electronic devices. To enrich the functionality of QD-based opto-electronic devices, colloidal semiconductor QDs have been frequently coupled with optical cavities to enable emission modulation. However, it remains a challenge to fully understand the interaction between the optical cavity resonance and the QD emission, especially for the planar optical microcavities. Here, we have investigated the light emission of colloidal semiconductor QDs in the planar Fabry-Perot microcavity consisted of two Ag mirrors. With the matched QD and cavity resonance, the microcavity coupled QD samples show a prominently narrower emission linewidth and emission angle range because of the efficient QD-cavity coupling, while with a slightly positive or negative energy detuning, the linewidth and angular distribution of the microcavity coupled QD emission both become broadened. Furthermore, with the standard lithography technique, the microcavity coupled QD sample can be patterned into arbitrary geometries, showing extra features of in-plane mode confinement. Our work highlights the important role of detuning in determining the coupling between colloidal semiconductor QDs and microcavities and paves the way for the future design of microcavity coupled QD devices.
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48
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Zhang J, Zhang L, Zhang Q. Unraveling the Effect of Surface Ligands on the Auger Process in an Inorganic Perovskite Quantum-Dot System. J Phys Chem Lett 2022; 13:2943-2949. [PMID: 35343682 DOI: 10.1021/acs.jpclett.2c00357] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
This work systematically scrutinizes the role of surface-ligand modification in affecting the Auger process in a porotype perovskite system of CsPbBr3-octanoic acid (OcA) and CsPbBr3-oleic acid (OA) quantum dots (QDs), by means of steady-state/time-resolved/temperature-dependent photoluminescence spectroscopy and ultrafast transient absorption spectroscopy. The difference in the ligand chain length (i.e., C8 and C18 alkyl chains for OcA and OA, respectively) is found to significantly affect Auger recombination and hot-carrier cooling processes. More importantly, we provide fresh insight into the involved carrier dynamics; i.e., the modification of CsPbBr3 QDs with short-chain (long-chain) ligand leads to the formation of trapped (free) carriers, which causes a pronounced difference in the ability to suppress the detrimental Auger process. In addition, a careful analysis of spectral evolution reveals that the Auger suppression is related to the carrier population of a certain transition state. The valuable mechanistic information gleaned from the exciton/carrier dynamics perspective would assist in surface engineering through a facile ligand-modification strategy toward rational design and optimization of QD-based photoelectrochemical applications.
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Affiliation(s)
- Jiachen Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Lei Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Qun Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
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49
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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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50
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Shi Y, Zhou LM, Liu AQ, Nieto-Vesperinas M, Zhu T, Hassanfiroozi A, Liu J, Zhang H, Tsai DP, Li H, Ding W, Zhu W, Yu YF, Mazzulla A, Cipparrone G, Wu PC, Chan CT, Qiu CW. Superhybrid Mode-Enhanced Optical Torques on Mie-Resonant Particles. NANO LETTERS 2022; 22:1769-1777. [PMID: 35156826 DOI: 10.1021/acs.nanolett.2c00050] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Circularly polarized light carries spin angular momentum, so it can exert an optical torque on the polarization-anisotropic particle by the spin momentum transfer. Here, we show that giant positive and negative optical torques on Mie-resonant (gain) particles arise from the emergence of superhybrid modes with magnetic multipoles and electric toroidal moments, excited by linearly polarized beams. Anomalous positive and negative torques on particles (doped with judicious amount of dye molecules) are over 800 and 200 times larger than the ordinary lossy counterparts, respectively. Meanwhile, a rotational motor can be configured by switching the s- and p-polarized beams, exhibiting opposite optical torques. These giant and reversed optical torques are unveiled for the first time in the scattering spectrum, paving another avenue toward exploring unprecedented physics of hybrid and superhybrid multipoles in metaoptics and optical manipulations.
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Affiliation(s)
- Yuzhi Shi
- National Key Laboratory of Science and Technology on Micro/Nano Fabrication, Department of Micro/Nano Electronics, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Lei-Ming Zhou
- Department of Optical Engineering, School of Physics, Hefei University of Technology, Hefei 230601, China
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583
| | - Ai Qun Liu
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798
| | - Manuel Nieto-Vesperinas
- Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas, Campus de Cantoblanco, Madrid 28049, Spain
| | - Tongtong Zhu
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian 116024, China
| | - Amir Hassanfiroozi
- Department of Photonics, National Cheng Kung University, Tainan 70101, Taiwan
| | - Jingquan Liu
- National Key Laboratory of Science and Technology on Micro/Nano Fabrication, Department of Micro/Nano Electronics, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hui Zhang
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798
| | - Din Ping Tsai
- Department of Electrical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Hang Li
- School of Physics, Harbin Institute of Technology, Harbin 150001, China
| | - Weiqiang Ding
- School of Physics, Harbin Institute of Technology, Harbin 150001, China
| | - Weiming Zhu
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054, China
| | - Ye Feng Yu
- School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Jiangsu 210094, China
| | - Alfredo Mazzulla
- CNR Nanotec─Institute of Nanotechnology, S.S. Cosenza, Rende, CS 87036, Italy
| | - Gabriella Cipparrone
- Department of Physics, University of Calabria, Ponte P. Bucci 31C, Rende, CS 87036, Italy
| | - Pin Chieh Wu
- Department of Photonics, National Cheng Kung University, Tainan 70101, Taiwan
| | - C T Chan
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Cheng-Wei Qiu
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583
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