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Hong Y, Yu C, Je H, Park JY, Kim T, Baik H, Tomboc GM, Kim Y, Ha JM, Joo J, Kim CW, Woo HY, Park S, Choi DH, Lee K. Perovskite Nanocrystals Protected by Hermetically Sealing for Highly Bright and Stable Deep-Blue Light-Emitting Diodes. Adv Sci (Weinh) 2023; 10:e2302906. [PMID: 37271888 PMCID: PMC10427390 DOI: 10.1002/advs.202302906] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Indexed: 06/06/2023]
Abstract
Metal-halide perovskite nanocrystals (NCs) have emerged as suitable light-emitting materials for light-emitting diodes (LEDs) and other practical applications. However, LEDs with perovskite NCs undergo environment-induced and ion-migration-induced structural degradation during operation; therefore, novel NC design concepts, such as hermetic sealing of the perovskite NCs, are required. Thus far, viable synthetic conditions to form a robust and hermetic semiconducting shell on perovskite NCs have been rarely reported for LED applications because of the difficulties in the delicate engineering of encapsulation techniques. Herein, a highly bright and durable deep-blue perovskite LED (PeLED) formed by hermetically sealing perovskite NCs with epitaxial ZnS shells is reported. This shell protects the perovskite NCs from the environment, facilitates charge injection/transport, and effectively suppresses interparticle ion migration during the LED operation, resulting in exceptional brightness (2916 cd m-2 ) at 451 nm and a high external quantum efficiency of 1.32%. Furthermore, even in the unencapsulated state, the LED shows a long operational lifetime (T50 ) of 1192 s (≈20 min) in the air. These results demonstrate that the epitaxial and hermetic encapsulation of perovskite NCs is a powerful strategy for fabricating high-performance deep-blue-emitting PeLEDs.
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Affiliation(s)
- Yongju Hong
- Department of Chemistry and Research Institute for Natural SciencesKorea UniversitySeoul02841Republic of Korea
| | - Chungman Yu
- Department of Chemistry and Research Institute for Natural SciencesKorea UniversitySeoul02841Republic of Korea
| | - Hyeondoo Je
- Department of Chemistry and Research Institute for Natural SciencesKorea UniversitySeoul02841Republic of Korea
| | - Jin Young Park
- Department of Chemistry and Research Institute for Natural SciencesKorea UniversitySeoul02841Republic of Korea
| | - Taekyung Kim
- Korea Basic Science Institute (KBSI)Seoul02841Republic of Korea
| | - Hionsuck Baik
- Korea Basic Science Institute (KBSI)Seoul02841Republic of Korea
| | - Gracita M. Tomboc
- Department of Chemistry and Research Institute for Natural SciencesKorea UniversitySeoul02841Republic of Korea
| | - Youngseo Kim
- Department of Chemistry and Research Institute for Natural SciencesKorea UniversitySeoul02841Republic of Korea
| | - Jung Min Ha
- Department of Chemistry and Research Institute for Natural SciencesKorea UniversitySeoul02841Republic of Korea
| | - Jinwhan Joo
- Department of Chemistry and Research Institute for Natural SciencesKorea UniversitySeoul02841Republic of Korea
| | - Chai Won Kim
- Department of Chemistry and Research Institute for Natural SciencesKorea UniversitySeoul02841Republic of Korea
| | - Han Young Woo
- Department of Chemistry and Research Institute for Natural SciencesKorea UniversitySeoul02841Republic of Korea
| | - Sungnam Park
- Department of Chemistry and Research Institute for Natural SciencesKorea UniversitySeoul02841Republic of Korea
| | - Dong Hoon Choi
- Department of Chemistry and Research Institute for Natural SciencesKorea UniversitySeoul02841Republic of Korea
| | - Kwangyeol Lee
- Department of Chemistry and Research Institute for Natural SciencesKorea UniversitySeoul02841Republic of Korea
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Pan S, Hu S, Wei B. Research on the High Light Out-Coupling Efficiency Deep-Blue Top-Emitting Organic Light-Emitting Diode through FDTD Optical Simulation. Nanomaterials (Basel) 2023; 13:1282. [PMID: 37049375 PMCID: PMC10097390 DOI: 10.3390/nano13071282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 03/30/2023] [Accepted: 04/03/2023] [Indexed: 06/19/2023]
Abstract
We have studied high light out-coupling efficiency top-emitting organic light-emitting diodes (TOLEDs) under the guidance of the finite-difference time-domain (FDTD) simulation. TOLED achieves an extraordinarily high light extraction efficiency at 468 nm, in deep-blue regions, of 49.70%, which is approximately 3.5 times that of the bottom light-emitting diode (BOLED) by changing the thickness of the organic layer and the position of the light-emitting layer in the FDTD simulation. Based on the simulation results, the TOLED with ultrahigh efficiency and narrow full width at half maximum is successfully fabricated, and the maximum external quantum efficiency of TOLED is almost 3.3 times that of the BOLED, which is perfectly consistent with the FDTD simulation results. Meanwhile, the shift of the electroluminescence spectrum of the TOLED is restricted within 10° in the angular-dependence test (0° to 80°). The optimized performance of the OLED indicates a new method to develop a high-performance device under the guidance of simulation.
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Affiliation(s)
- Saihu Pan
- School of Microelectronics and Control Engineering, Changzhou University, Changzhou 213164, China
| | - Suhao Hu
- School of Microelectronics and Control Engineering, Changzhou University, Changzhou 213164, China
| | - Bin Wei
- School of Microelectronics and Control Engineering, Changzhou University, Changzhou 213164, China
- Key Laboratory of Advanced Display and System Applications, Ministry of Education, Shanghai University, Shanghai 200072, China
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Li J, Gong H, Zhang J, Liu H, Tao L, Wang Y, Guo Q. Efficient Exciplex-Based Deep-Blue Organic Light-Emitting Diodes Employing a Bis(4-fluorophenyl)amine-Substituted Heptazine Acceptor. Molecules 2021; 26:5568. [PMID: 34577041 PMCID: PMC8466596 DOI: 10.3390/molecules26185568] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Revised: 09/03/2021] [Accepted: 09/10/2021] [Indexed: 11/25/2022] Open
Abstract
The realization of a deep-blue-emitting exciplex system is a herculean task in the field of organic light-emitting diodes (OLEDs) on account of a large red-shifted and broadened exciplex emission spectrum in comparison to those of the corresponding single compounds. Herein, 2,5,8-tris(di(4-fluorophenyl)amine)-1,3,4,6,7,9,9b-heptaazaphenalene (HAP-3FDPA) was designed as an electron acceptor by integrating three bis(4-fluorophenyl)amine groups into a heptazine core, while 1,3-di(9H-carbazol-9-yl)benzene (mCP) possessing two electron-donating carbazole moieties was chosen as the electron donor. Excitingly, the exciplex system of 8 wt% HAP-3FDPA:mCP exhibited deep-blue emission and a high photoluminescence quantum yield of 53.2%. More importantly, an OLED containing this exciplex system as an emitting layer showed deep-blue emission with Commission Internationale de l'Eclairage coordinates of (0.16, 0.12), a peak luminance of 15,148 cd m-2, and a rather high maximum external quantum efficiency of 10.2% along with a low roll-off. This study not only reports an efficient exciplex-based deep-blue emitter but also presents a feasible pathway to construct highly efficient deep-blue OLEDs based on exciplex systems.
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Affiliation(s)
- Jie Li
- College of Optoelectronic Engineering, Chengdu University of Information Technology, Chengdu 610225, China; (J.L.); (H.G.); (J.Z.); (H.L.); (L.T.)
| | - Heqi Gong
- College of Optoelectronic Engineering, Chengdu University of Information Technology, Chengdu 610225, China; (J.L.); (H.G.); (J.Z.); (H.L.); (L.T.)
| | - Jincheng Zhang
- College of Optoelectronic Engineering, Chengdu University of Information Technology, Chengdu 610225, China; (J.L.); (H.G.); (J.Z.); (H.L.); (L.T.)
| | - Hui Liu
- College of Optoelectronic Engineering, Chengdu University of Information Technology, Chengdu 610225, China; (J.L.); (H.G.); (J.Z.); (H.L.); (L.T.)
| | - Li Tao
- College of Optoelectronic Engineering, Chengdu University of Information Technology, Chengdu 610225, China; (J.L.); (H.G.); (J.Z.); (H.L.); (L.T.)
| | - Yanqing Wang
- College of Polymer Science and Engineering, Sichuan University, Chengdu 610065, China;
| | - Qiang Guo
- College of Optoelectronic Engineering, Chengdu University of Information Technology, Chengdu 610225, China; (J.L.); (H.G.); (J.Z.); (H.L.); (L.T.)
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Chen H, Shi M, Liu M, Xing X, Zhao C, Miao J, Ali MU, Facchetti A, Meng H. Host-Free Deep-Blue Organic Light-Emitting Transistors Based on a Novel Fluorescent Emitter. ACS Appl Mater Interfaces 2020; 12:40558-40565. [PMID: 32815711 DOI: 10.1021/acsami.0c08721] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Organic light-emitting transistors (OLETs), with the capability of simultaneously functioning as a light-emitting stack and a thin-film transistor, have received considerable attention for potential applications in active-matrix flat-panel displays. Here, we demonstrate host-free deep-blue OLETs based on a novel small-molecule fluorescent emitter, 10,10'-bis(4-(1-phenyl-1H-benzo[d]imidazol-2-yl)phenyl)-10H,10'H-9,9'-spirobi[acridine] (SPA-PBI), and a high-k dielectric, cross-linked poly(vinyl alcohol) (PVA) polymer. The deep-blue OLETs based on 2,2',2″-(1,3,5-benzinetriyl)-tris(1-phenyl-1-H-benzimidazole) (TPBi) as an electron-transport layer showed an extraordinarily high hole mobility of 4.6 cm2 V-1 s-1, a brightness of 570 cd m-2 under a low gate and source-drain voltages of -24 V, and an external quantum efficiency (EQE) of 0.87% at 100 cd m-2. Besides, an electroluminescence peak was observed to be at 432 nm and the corresponding CIE coordinates were as deep as (0.16, 0.08). By replacing TPBi with TmPyPB as the electron-transport layer (ETL), the electron transport and hole blocking capability were greatly improved, which led to ∼60% enhancement of the EQE (1.39% at 100 cd m-2). These results suggest that using a highly twisted double-donor-acceptor emitter with rationally optimized charge injection could lead to highly efficient deep-blue OLETs.
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Affiliation(s)
- Hongming Chen
- School of Advanced Materials, Peking University Shenzhen Graduate School, Peking University, Shenzhen 518055, P. R. China
| | - Ming Shi
- School of Advanced Materials, Peking University Shenzhen Graduate School, Peking University, Shenzhen 518055, P. R. China
| | - Ming Liu
- School of Advanced Materials, Peking University Shenzhen Graduate School, Peking University, Shenzhen 518055, P. R. China
| | - Xing Xing
- Research & Development Institute of Northwest Polytechnical University (Shenzhen), Northwestern Polytechnical University, Shenzhen 518057, P. R. China
| | - Changbin Zhao
- School of Advanced Materials, Peking University Shenzhen Graduate School, Peking University, Shenzhen 518055, P. R. China
| | - Jingsheng Miao
- School of Advanced Materials, Peking University Shenzhen Graduate School, Peking University, Shenzhen 518055, P. R. China
| | - Muhammad Umair Ali
- School of Advanced Materials, Peking University Shenzhen Graduate School, Peking University, Shenzhen 518055, P. R. China
- Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 100871, P. R. China
| | - Antonio Facchetti
- Department of Chemistry and the Materials Research Center, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
- Flexterra Corporation, 8025 Lamon Avenue, Skokie, Illinois 60077, United States
| | - Hong Meng
- School of Advanced Materials, Peking University Shenzhen Graduate School, Peking University, Shenzhen 518055, P. R. China
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Peng S, Wen Z, Ye T, Xiao X, Wang K, Xia J, Sun J, Zhang T, Mei G, Liu H, Xu B, Li X, Chen R, Xing G, Wang K, Tang Z. Effective Surface Ligand-Concentration Tuning of Deep-Blue Luminescent FAPbBr 3 Nanoplatelets with Enhanced Stability and Charge Transport. ACS Appl Mater Interfaces 2020; 12:31863-31874. [PMID: 32567298 DOI: 10.1021/acsami.0c08552] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Metal-halide perovskite-based green and red light-emitting diodes (LEDs) have witnessed a rapid development because of their facile synthesis and processability; however, the blue-band emission is constrained by their unstable chemical properties and poorly conducting emitting layers. Here, we show a trioctylphosphine oxide (TOPO)-mediated one-step approach to realize bright deep-blue luminescent FAPbBr3 nanoplatelets (NPLs) with enhanced stability and charge transport. The concentration of NPL surface ligands is shown to be progressively tuned via varying the amount of intermediate TOPO due to the acid-base equilibrium between protic acid and TOPO. By effectively optimizing the concentration of surface ligands, the structural integrity of NPL solids can be preserved in ambient air for a week, mainly because of the highly ordered and dense solid assembly and the reduced defects. The removal of excess organic ligands also enables the improvement of charge mobility by orders of magnitude. Ultimately, ultrapure deep-blue perovskite LEDs (439 nm) with a narrow emission width of 14 nm and a peak EQE of 0.14% are achieved at low driving voltage. Our finding expands the current understanding of surface ligand modulation in the development of pure bromide deep-blue perovskite optoelectronics.
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Affiliation(s)
- Shaomin Peng
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Macao SAR 999078, China
- Shenzhen Key Laboratory for Advanced Quantum Dot Displays and Lighting, Department of Electrical & Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Zuoliang Wen
- Shenzhen Key Laboratory for Advanced Quantum Dot Displays and Lighting, Department of Electrical & Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Taikang Ye
- Shenzhen Key Laboratory for Advanced Quantum Dot Displays and Lighting, Department of Electrical & Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Xiangtian Xiao
- Shenzhen Key Laboratory for Advanced Quantum Dot Displays and Lighting, Department of Electrical & Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Kaiyang Wang
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Macao SAR 999078, China
| | - Junmin Xia
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Macao SAR 999078, China
| | - Jiayun Sun
- Shenzhen Key Laboratory for Advanced Quantum Dot Displays and Lighting, Department of Electrical & Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Tianqi Zhang
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Macao SAR 999078, China
- Shenzhen Key Laboratory for Advanced Quantum Dot Displays and Lighting, Department of Electrical & Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Guanding Mei
- Shenzhen Key Laboratory for Advanced Quantum Dot Displays and Lighting, Department of Electrical & Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, 999077, China
| | - Haochen Liu
- Shenzhen Key Laboratory for Advanced Quantum Dot Displays and Lighting, Department of Electrical & Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Bing Xu
- Shenzhen Key Laboratory for Advanced Quantum Dot Displays and Lighting, Department of Electrical & Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Xiaojun Li
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Macao SAR 999078, China
| | - Rui Chen
- Shenzhen Key Laboratory for Advanced Quantum Dot Displays and Lighting, Department of Electrical & Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Guichuan Xing
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Macao SAR 999078, China
| | - Kai Wang
- Shenzhen Key Laboratory for Advanced Quantum Dot Displays and Lighting, Department of Electrical & Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Zikang Tang
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Macao SAR 999078, China
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Zheng XH, Zhao JW, Chen X, Cai R, Yang GX, Zhu JJ, Tang SS, Lin ZH, Tao SL, Tong QX. Imidazo[1,2-a]pyridine as an Electron Acceptor to Construct High-Performance Deep-Blue Organic Light-Emitting Diodes with Negligible Efficiency Roll-Off. Chemistry 2020; 26:8588-8596. [PMID: 32187750 DOI: 10.1002/chem.202000518] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/17/2020] [Indexed: 01/09/2023]
Abstract
Two novel bipolar deep-blue fluorescent emitters, IP-PPI and IP-DPPI, featuring different lengths of the phenyl bridge, were designed and synthesized, in which imidazo[1,2-a]pyridine (IP) and phenanthroimidazole (PI) were proposed as an electron acceptor and an electron donor, respectively. Both of them exhibit outstanding thermal stability and high emission quantum yields. All the devices based on these two materials showed negligible efficiency roll-off with increasing current density. Impressively, non-doped organic light-emitting diodes (OLEDs) based on IP-PPI and IP-DPPI exhibited external quantum efficiencies (EQEs) of 4.85 % and 4.74 % with CIE coordinates of (0.153, 0.097) and (0.154, 0.114) at 10000 cd m-2 , respectively. In addition, the 40 wt % IP-PPI doped device maintained a high EQE of 5.23 % with CIE coordinates of (0.154, 0.077) at 10000 cd m-2 . The doped device based on 20 wt % IP-DPPI exhibited a higher deep-blue electroluminescence (EL) performance with a maximum EQE of up to 6.13 % at CIE of (0.153, 0.078) and maintained an EQE of 5.07 % at 10000 cd m-2 . To the best of our knowledge, these performances are among the state-of-the art devices with CIEy ≤0.08 at a high brightness of 10000 cd m-2 . Furthermore, by doping a red phosphorescent dye Ir(MDQ)2 (MDQ=2-methyldibenzo[f,h]quinoxaline) into the IP-PPI and IP-DPPI hosts, high-performance red phosphorescent OLEDs with EQEs of 20.8 % and 19.1 % were achieved, respectively. This work may provide a new approach for designing highly efficient deep-blue emitters with negligible roll-off for OLED applications.
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Affiliation(s)
- Xu-Hui Zheng
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P. R. China
| | - Jue-Wen Zhao
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China (UESTC), Chengdu, 610054, P. R. China
| | - Xiang Chen
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P. R. China
| | - Ruoke Cai
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P. R. China
| | - Guo-Xi Yang
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P. R. China
| | - Jie-Ji Zhu
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P. R. China
| | - Shan-Shun Tang
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P. R. China
| | - Zhi-Hong Lin
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P. R. China
| | - Si-Lu Tao
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China (UESTC), Chengdu, 610054, P. R. China
| | - Qing-Xiao Tong
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P. R. China
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Wang L, Shi Z, Ma Z, Yang D, Zhang F, Ji X, Wang M, Chen X, Na G, Chen S, Wu D, Zhang Y, Li X, Zhang L, Shan C. Colloidal Synthesis of Ternary Copper Halide Nanocrystals for High-Efficiency Deep-Blue Light-Emitting Diodes with a Half-Lifetime above 100 h. Nano Lett 2020; 20:3568-3576. [PMID: 32243171 DOI: 10.1021/acs.nanolett.0c00513] [Citation(s) in RCA: 85] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Currently, the blue perovskite light-emitting diodes (PeLEDs) suffer from a compromise in lead toxicity and poor operation stability, and most previous studies have struggled to meet the crucial blue NTSC standard. In this study, electrically driven deep-blue LEDs (∼445 nm) based on zero-dimensional (0D) Cs3Cu2I5 nanocrystals (NCs) were demonstrated with the color coordinates of (0.16, 0.07) and a high external quantum efficiency of ∼1.12%, comparable with the best-performing blue LEDs based on lead-halide perovskites. Encouraged by the remarkable stability of Cs3Cu2I5 NCs against heat and environmental oxygen/moisture, the proposed device was operated in a continuous current mode for 170 h, producing a record half-lifetime of ∼108 h. The device stability was further verified by an aggressive thermal cycling test (300-360-300 K) and a 35-day storage test. Together with the eco-friendly features and facile colloidal synthesis technique, the 0D Cs3Cu2I5 NCs can be therefore regarded as a promising candidate for deep-blue LEDs applications.
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Affiliation(s)
- Lintao Wang
- Key Laboratory of Materials Physics of Ministry of Education, School of Physics and Microelectronics, Zhengzhou University, Daxue Road 75, Zhengzhou 450052, China
| | - Zhifeng Shi
- Key Laboratory of Materials Physics of Ministry of Education, School of Physics and Microelectronics, Zhengzhou University, Daxue Road 75, Zhengzhou 450052, China
| | - Zhuangzhuang Ma
- Key Laboratory of Materials Physics of Ministry of Education, School of Physics and Microelectronics, Zhengzhou University, Daxue Road 75, Zhengzhou 450052, China
| | - Dongwen Yang
- Key Laboratory of Materials Physics of Ministry of Education, School of Physics and Microelectronics, Zhengzhou University, Daxue Road 75, Zhengzhou 450052, China
| | - Fei Zhang
- Key Laboratory of Materials Physics of Ministry of Education, School of Physics and Microelectronics, Zhengzhou University, Daxue Road 75, Zhengzhou 450052, China
| | - Xinzhen Ji
- Key Laboratory of Materials Physics of Ministry of Education, School of Physics and Microelectronics, Zhengzhou University, Daxue Road 75, Zhengzhou 450052, China
| | - Meng Wang
- Key Laboratory of Materials Physics of Ministry of Education, School of Physics and Microelectronics, Zhengzhou University, Daxue Road 75, Zhengzhou 450052, China
| | - Xu Chen
- Key Laboratory of Materials Physics of Ministry of Education, School of Physics and Microelectronics, Zhengzhou University, Daxue Road 75, Zhengzhou 450052, China
| | - Guangren Na
- State Key Laboratory on Integrated Optoelectronics, Key Laboratory of Automobile Materials of MOE, and College of Materials Science and Engineering, Jilin University, Changchun 130012, China
| | - Shu Chen
- Key Laboratory of Materials Physics of Ministry of Education, School of Physics and Microelectronics, Zhengzhou University, Daxue Road 75, Zhengzhou 450052, China
| | - Di Wu
- Key Laboratory of Materials Physics of Ministry of Education, School of Physics and Microelectronics, Zhengzhou University, Daxue Road 75, Zhengzhou 450052, China
| | - Yu Zhang
- State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Qianjin Street 2699, Changchun 130012, China
| | - Xinjian Li
- Key Laboratory of Materials Physics of Ministry of Education, School of Physics and Microelectronics, Zhengzhou University, Daxue Road 75, Zhengzhou 450052, China
| | - Lijun Zhang
- State Key Laboratory on Integrated Optoelectronics, Key Laboratory of Automobile Materials of MOE, and College of Materials Science and Engineering, Jilin University, Changchun 130012, China
| | - Chongxin Shan
- Key Laboratory of Materials Physics of Ministry of Education, School of Physics and Microelectronics, Zhengzhou University, Daxue Road 75, Zhengzhou 450052, China
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De J, Yang WY, Bala I, Gupta SP, Yadav RAK, Dubey DK, Chowdhury A, Jou JH, Pal SK. Room-Temperature Columnar Liquid Crystals as Efficient Pure Deep-Blue Emitters in Organic Light-Emitting Diodes with an External Quantum Efficiency of 4.0. ACS Appl Mater Interfaces 2019; 11:8291-8300. [PMID: 30707013 DOI: 10.1021/acsami.8b18749] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A novel design of aggregation-induced emission (AIE) active columnar (Col) luminomesogens is reported, and they are demonstrated to act as highly efficient deep-blue emitters in organic light-emitting diodes (OLEDs). All derivatives exhibit Col liquid crystalline (LC) behavior at room temperature over a wide temperature range and desirable alignment properties, which is very important in using them as materials for organic electronic devices. These new AIE active luminomesogens were found to act as highly efficient emitters in OLEDs and unveiled a maximum external quantum efficiency of 4.0% for the first time in Col LCs with Commission International de l'E'clairage coordinates of (0.17, 0.07), which closely matches the National Television System Committee (NTSC) standard, corresponding to pure deep blue color. The detailed supramolecular assembly of the compounds has been characterized by modeling in the mesophase derived from small- and wide-angle X-ray scattering results.
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Affiliation(s)
- Joydip De
- Department of Chemical Sciences , Indian Institute of Science Education and Research (IISER) Mohali , Sector-81, SAS Nagar, Knowledge City , Manauli 140306 , India
| | - Wan-Yun Yang
- Department of Materials Science and Engineering , National Tsing Hua University , Hsinchu 30013 , Taiwan
| | - Indu Bala
- Department of Chemical Sciences , Indian Institute of Science Education and Research (IISER) Mohali , Sector-81, SAS Nagar, Knowledge City , Manauli 140306 , India
| | | | - Rohit Ashok Kumar Yadav
- Department of Materials Science and Engineering , National Tsing Hua University , Hsinchu 30013 , Taiwan
| | - Deepak Kumar Dubey
- Department of Materials Science and Engineering , National Tsing Hua University , Hsinchu 30013 , Taiwan
| | - Arjun Chowdhury
- Department of Chemical Sciences , Indian Institute of Science Education and Research (IISER) Mohali , Sector-81, SAS Nagar, Knowledge City , Manauli 140306 , India
| | - Jwo-Huei Jou
- Department of Materials Science and Engineering , National Tsing Hua University , Hsinchu 30013 , Taiwan
| | - Santanu Kumar Pal
- Department of Chemical Sciences , Indian Institute of Science Education and Research (IISER) Mohali , Sector-81, SAS Nagar, Knowledge City , Manauli 140306 , India
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Hamilton I, Chander N, Cheetham NJ, Suh M, Dyson M, Wang X, Stavrinou PN, Cass M, Bradley DDC, Kim JS. Controlling Molecular Conformation for Highly Efficient and Stable Deep-Blue Copolymer Light-Emitting Diodes. ACS Appl Mater Interfaces 2018; 10:11070-11082. [PMID: 29508604 DOI: 10.1021/acsami.8b00243] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We report a novel approach to achieve deep-blue, high-efficiency, and long-lived solution-processed polymer light-emitting diodes (PLEDs) via a simple molecular level conformation change of an emissive conjugated polymer. We introduce rigid β-phase segments into a 95% fluorene-5% arylamine copolymer emissive layer. The arylamine moieties at low density act as efficient exciton formation sites in PLEDs, whereas the conformational change alters the nature of the dominant luminescence from a broad, charge transfer like emission to a significantly blue-shifted and highly vibronically structured excitonic emission. As a consequence, we observe a significant improvement in the Commission International de L'Eclairage ( x, y) coordinates from (0.149, 0.175) to (0.145, 0.123) while maintaining high efficiency and improved stability. We achieve a peak luminous efficiency, η = 3.60 cd/A, and a luminous power efficiency, ηw = 2.44 lm/W, values that represent state-of-the-art performance for single copolymer deep-blue PLEDs. These values are 5-fold better than for otherwise-equivalent, β-phase poly(9,9-dioctylfluorene) PLEDs (0.70 cd/A and 0.38 lm/W). This report represents the first demonstration of the use of molecular conformation as a simple but effective method to control the optoelectronic properties of a fluorene copolymer; previous examples have been confined to homopolymers.
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Affiliation(s)
- Iain Hamilton
- Department of Physics and Centre for Plastic Electronics , Imperial College London , London SW7 2AZ , U.K
| | - Nathan Chander
- Department of Physics and Centre for Plastic Electronics , Imperial College London , London SW7 2AZ , U.K
| | - Nathan J Cheetham
- Department of Physics and Centre for Plastic Electronics , Imperial College London , London SW7 2AZ , U.K
| | - Minwon Suh
- Department of Physics and Centre for Plastic Electronics , Imperial College London , London SW7 2AZ , U.K
| | - Matthew Dyson
- Department of Physics and Centre for Plastic Electronics , Imperial College London , London SW7 2AZ , U.K
- Molecular Materials and Nanosystems and Institute for Complex Molecular Systems , Eindhoven University of Technology , P.O. Box 513, 5600 MB Eindhoven , The Netherlands
| | - Xuhua Wang
- Department of Physics and Centre for Plastic Electronics , Imperial College London , London SW7 2AZ , U.K
| | - Paul N Stavrinou
- Department of Engineering Science , University of Oxford , Parks Road , Oxford OX1 3PJ , U.K
| | - Michael Cass
- Cambridge Display Technology Ltd , Unit 12 Cardinal Park , Godmanchester, Cambridgeshire PE29 2XG , U.K
| | - Donal D C Bradley
- Department of Engineering Science , University of Oxford , Parks Road , Oxford OX1 3PJ , U.K
- Department of Physics and Division of Mathematical, Physical and Life Sciences , University of Oxford , 9 Parks Road , Oxford OX1 3PD , U.K
| | - Ji-Seon Kim
- Department of Physics and Centre for Plastic Electronics , Imperial College London , London SW7 2AZ , U.K
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Sun W, Zhou N, Xiao Y, Wang S, Li X. A Novel Spiro[acridine-9,9'-fluorene] Derivatives Containing Phenanthroimidazole Moiety for Deep-Blue OLED Application. Chem Asian J 2017; 12:3069-76. [PMID: 28984424 DOI: 10.1002/asia.201701292] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Typical π-π stacking and aggregation-caused quenching could be suppressed in the film-state by the spiro conformation molecular design in the field of organic light-emitting diodes (OLEDs). Herein, a novel deep-blue fluorescent material with spiro conformation, 1-(4-(tert-butyl)phenyl)-2-(4-(10-phenyl-10H-spiro[acridine-9,9'-fluoren]-2-yl)phenyl)-1H-phenanthro[9,10-d]imidazole (SAF-BPI), was designed and synthesized. The compound consists of spiro-acridine-fluorene (SAF) as donor part and phenanthroimidazole (BPI) as acceptor part. Owing to the rigid SAF skeleton, this compound exhibits a high thermal stability with a glass transition temperature (Tg ) of 198 °C. The compound exhibits bipolar transporting characteristics demonstrated by the single-carrier devices. The non-doped OLEDs based on the SAF-BPI as the emitting layer shows maximum emission at 448 nm, maximum luminance of 2122 cd m-2 , maximum current efficiency (CE) of 3.97 cd A-1 , and a maximum power efficiency of 2.08 lm W-1 . The chromaticity coordinate is stable at (0.15, 0.10) at the voltage of 7-11 V. The device shows a slow efficiency roll-off with CE of 3.35 and 2.85 cd A-1 at 100 and 1000 cd m-2 , respectively.
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Xia L, Xue Y, Xiong K, Cai C, Peng Z, Wu Y, Li Y, Miao J, Chen D, Hu Z, Wang J, Peng X, Mo Y, Hou L. Highly Improved Efficiency of Deep-Blue Fluorescent Polymer Light-Emitting Device Based on a Novel Hole Interface Modifier with 1,3,5-Triazine Core. ACS Appl Mater Interfaces 2015; 7:26405-26413. [PMID: 26422296 DOI: 10.1021/acsami.5b06068] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We present an investigation of deep-blue fluorescent polymer light-emitting diodes (PLEDs) with a novel functional 1,3,5-triazine core material (HQTZ) sandwiched between poly(3,4-ethylene dioxythiophene):poly(styrene sulfonic acid) layer and poly(vinylcarbazole) layer as a hole injection layer (HIL) without interface intermixing. Ultraviolet photoemission spectroscopy and Kelvin probe measurements were carried out to determine the change of anode work function influenced by the HQTZ modifier. The thin HQTZ layer can efficiently maximize the charge injection from anode to blue emitter and simultaneously enhance the hole mobility of HILs. The deep-blue device performance is remarkably improved with the maximum luminous efficiency of 4.50 cd/A enhanced by 80% and the maximum quantum efficiency of 4.93%, which is 1.8-fold higher than that of the conventional device without HQTZ layer, including a lower turn-on voltage of 3.7 V and comparable Commission Internationale de L'Eclairage coordinates of (0.16, 0.09). It is the highest efficiency ever reported to date for solution-processed deep-blue PLEDs based on the device structure of ITO/HILs/poly(9,9-dialkoxyphenyl-2,7-silafluorene)/CsF/AL. The results indicate that HQTZ based on 1,3,5-triazine core can be a promising candidate of interfacial materials for deep-blue fluorescent PLEDs.
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Affiliation(s)
- Lianpeng Xia
- Siyuan Laboratory, Department of Physics, Jinan University , Guangzhou 510632, P.R. China
| | - Yuyuan Xue
- Siyuan Laboratory, Department of Physics, Jinan University , Guangzhou 510632, P.R. China
- School of Chemistry and Chemical Engineering, South China University of Technology , Guangzhou 510640, P.R. China
| | - Kang Xiong
- Siyuan Laboratory, Department of Physics, Jinan University , Guangzhou 510632, P.R. China
| | - Chaosheng Cai
- Siyuan Laboratory, Department of Physics, Jinan University , Guangzhou 510632, P.R. China
| | - Zuosheng Peng
- Siyuan Laboratory, Department of Physics, Jinan University , Guangzhou 510632, P.R. China
| | - Ying Wu
- School of Chemistry and Chemical Engineering, South China University of Technology , Guangzhou 510640, P.R. China
| | - Yuan Li
- School of Chemistry and Chemical Engineering, South China University of Technology , Guangzhou 510640, P.R. China
| | - Jingsheng Miao
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology , Guangzhou 510640, P.R. China
| | - Dongcheng Chen
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology , Guangzhou 510640, P.R. China
| | - Zhanhao Hu
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology , Guangzhou 510640, P.R. China
| | - Jianbin Wang
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology , Guangzhou 510640, P.R. China
| | - Xiaobin Peng
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology , Guangzhou 510640, P.R. China
| | - Yueqi Mo
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology , Guangzhou 510640, P.R. China
| | - Lintao Hou
- Siyuan Laboratory, Department of Physics, Jinan University , Guangzhou 510632, P.R. China
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