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Godi M, Kwon H, Park S, Park S, Lee H, Lee K, Park J. Enhancing OLED emitter efficiency through increased rigidity. RSC Adv 2024; 14:8135-8144. [PMID: 38464691 PMCID: PMC10921275 DOI: 10.1039/d3ra07937f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 03/04/2024] [Indexed: 03/12/2024] Open
Abstract
Three new blue materials, TPI-InCz, PAI-InCz, and CN-PAI-InCz, have been developed. In the film state, TPI-InCz and PAI-InCz exhibited emission peaks at 411 and 431 nm indicating deep blue emission. CN-PAI-InCz showed a peak emission at 452 nm, within the real blue region. When these three materials were used as the emissive layer to fabricate non-doped devices, CN-PAI-InCz showed the highest current efficiency of 2.91 cd A-1, power efficiency of 1.93 lm W-1, and external quantum efficiency of 3.31%. Among the synthesized materials, CN-PAI-InCz exhibited superior charge balance due to the introduction of CN groups, as confirmed by hole-only devices and electron-only devices. PAI-InCz demonstrated fast hole mobility with a value of 1.50 × 10-3 cm2 V-1 s-1, attributed to its planar and highly rigid structure. In the resulting devices, the Commission Internationale de l'Eclairage coordinates for TPI-InCz, PAI-InCz, and CN-PAI-InCz were (0.162, 0.048), (0.0161, 0.067), and (0.155, 0.099), all indicating emission in the blue region.
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Affiliation(s)
- Mahendra Godi
- Integrated Engineering, Department of Chemical Engineering, Kyung Hee University Gyeonggi 17104 Republic of Korea
| | - Hyukmin Kwon
- Integrated Engineering, Department of Chemical Engineering, Kyung Hee University Gyeonggi 17104 Republic of Korea
| | - Sangwook Park
- Integrated Engineering, Department of Chemical Engineering, Kyung Hee University Gyeonggi 17104 Republic of Korea
| | - Sunwoo Park
- Integrated Engineering, Department of Chemical Engineering, Kyung Hee University Gyeonggi 17104 Republic of Korea
| | - Hayoon Lee
- Integrated Engineering, Department of Chemical Engineering, Kyung Hee University Gyeonggi 17104 Republic of Korea
| | - Kiho Lee
- Integrated Engineering, Department of Chemical Engineering, Kyung Hee University Gyeonggi 17104 Republic of Korea
| | - Jongwook Park
- Integrated Engineering, Department of Chemical Engineering, Kyung Hee University Gyeonggi 17104 Republic of Korea
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2
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Keruckiene R, Guzauskas M, Volyniuk D, da Silva Filho DA, Sini G, Grazulevicius JV. Computational and spectral analysis of derivatives of 9,9-dimethyl-9,10-dihydroacridine and 10-Phenyl-10H-phenothiazine-5,5-dioxide with hybridized local and charge-transfer excited states for optoelectronic applications. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2023; 303:123200. [PMID: 37549458 DOI: 10.1016/j.saa.2023.123200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 06/25/2023] [Accepted: 07/21/2023] [Indexed: 08/09/2023]
Abstract
Aiming to combine the advantages of both prompt fluorescence and thermally activated delayed fluorescence in single emitter, molecular design of emitters with hybridized locally excited and charge transfer states were investigated by computational approaches and optical spectroscopy. Taking into account the results of the theoretical screening, the most promising derivatives of 9,9-dimethyl-9,10-dihydroacridine and 10-phenyl-10H-phenothiazine-5,5-dioxide based with the different linking topology (meta- and para-isomers) were selected for the synthesis and experimental investigations. Both the compounds exhibit ultraviolet LE emission peaking at ca. 360 nm, green ICT peaking at ca. 510 nm, and deep-blue HLCT emission peaking at ca. 430 nm when they are molecularly dispersed in the solid media of the different polarity. The developed emitters allow to obtain deep-blue electroluminescence for the host-containing OLEDs and green electroluminescence of host-free devices with the efficiency of exciton production of 42 and 73%, respectively. Efficient exciton production is due to the spin-flip switching via thermally activated processes which is much more efficient than prompt fluorescence. Showing the impact of the linking topology, the para-isomer demonstrated more efficient triplet harvesting in OLEDs than meta-isomer. A detailed discussion on the structure-property relationships and on some discrepancies between the results of the results of theoretical calculations and spectral analysis allows to obtain important insights on the photophysical properties of these compounds.
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Affiliation(s)
- R Keruckiene
- Department of Polymer Chemistry and Technology, Kaunas University of Technology, K. Barsausko St. 59, LT-50254 Kaunas, Lithuania
| | - M Guzauskas
- Department of Polymer Chemistry and Technology, Kaunas University of Technology, K. Barsausko St. 59, LT-50254 Kaunas, Lithuania
| | - D Volyniuk
- Department of Polymer Chemistry and Technology, Kaunas University of Technology, K. Barsausko St. 59, LT-50254 Kaunas, Lithuania
| | - Demetrio A da Silva Filho
- Institute for Advanced Studies, CY Cergy Paris Université, 1 rue Descartes, 95000 Neuville-sur-Oise, France; Institute of Physics, University of Brasilia, 70919-970 Brasilia, Brazil; Laboratoire de Physicochimie des Polymères et des Interfaces, CY Paris Cergy Université, EA 2528, 5 mail Gay-Lussac, Cergy-Pontoise Cedex 95031, France
| | - G Sini
- Laboratoire de Physicochimie des Polymères et des Interfaces, CY Paris Cergy Université, EA 2528, 5 mail Gay-Lussac, Cergy-Pontoise Cedex 95031, France.
| | - J V Grazulevicius
- Department of Polymer Chemistry and Technology, Kaunas University of Technology, K. Barsausko St. 59, LT-50254 Kaunas, Lithuania.
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3
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Liao C, Chen B, Xie Q, Li X, Liu H, Wang S. A Breakthrough in Solution-Processed Ultra-Deep-Blue HLCT OLEDs: A Record External Quantum Efficiency Exceeding 10% Based on Novel V-Shaped Emitters. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2305310. [PMID: 37523270 DOI: 10.1002/adma.202305310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 07/28/2023] [Indexed: 08/02/2023]
Abstract
It is always a great challenge to achieve high-efficiency solution-processed ultra-deep-blue organic light-emitting diodes (OLEDs) with the Commission Internationale de l'Eclairage (CIE) 1931 chromaticity coordinates matching the blue primary of Rec. International Telecommunication Union-Radiocommunication BT.2100, which specifies high dynamic range television image parameters. Inspired by hybrid local and charge transfer (HLCT) excited state emitters improving exciton utilization through high-lying reverse intersystem crossing, here, a series of high-performance blue emitters by a V-shaped symmetric donor (D)-π-acceptor (A)-π-D design strategy are developed. Here, the large torsions and unstable bonds of D-A structures can be improved through π bridges, and also the conjugation length and donor groups can be easily adjusted. The obtained emitters merit excellent photophysical and electrochemical properties, thermal stability, solution processibility, and HLCT excited state excellence. Results suggest that the OLEDs based on the obtained blue emitters all achieve high maximum external quantum efficiency (EQEmax ) of more than 8% with very low efficiency roll-off. In particular, the device based on 4',5'-bis(4-(9H-carbazol-9-yl)phenyl)spiro[fluorene-9,2'-imidazole] exhibits a satisfactory ultra-deep-blue emission (CIEx , y = 0.1579, 0.0387) and a record-high EQEmax (10.40%) among solution-processed HLCT OLEDs, which is very close to the record EQEmax of devices by vacuum vapor deposition technology.
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Affiliation(s)
- Chuanxin Liao
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300072, China
| | - Bo Chen
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300072, China
| | - Qi Xie
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300072, China
| | - Xianggao Li
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300072, China
| | - Hongli Liu
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300072, China
| | - Shirong Wang
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300072, China
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Yang J, Zheng W, Hu D, Zhu F, Ma Y, Yan D. An Efficient Blue-Emission Crystalline Thin-Film OLED Sensitized by "Hot Exciton" Fluorescent Dopant. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2203997. [PMID: 36394078 PMCID: PMC9839864 DOI: 10.1002/advs.202203997] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 09/30/2022] [Indexed: 05/29/2023]
Abstract
Crystalline thin-film organic light-emitting diodes (C-OLEDs) can achieve a large light emission and a low Joule-heat loss under low driving voltage due to the high carrier mobility of the crystalline thin films. However, it is urgent for the C-OLEDs to improve their external quantum efficiency (EQE). Here, a novel strategy is proposed using a doped "hot exciton" material to sensitize a high PLQY blue emitter in C-OLEDs. Benefiting from the capability of the "hot exciton" material harnessing triplet/singlet excitons, the C-OLED exhibits an efficiency breakthrough with a maximum EQE of 6.2%, a much enhanced blue photon output with pure blue emission Commission International de L'Eclairage (CIE) (0.14, 0.15), a low turn-on/operation voltage of 2.6 V(@1 cd m-2 )/3.8 V (@1000 cd m-2 ), and a maximum power efficiency (PE) of 9.4 lm W-1 . This work unlocks the potential of C-OLEDs for achieving high photon output with high EQE.
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Affiliation(s)
- Jingjie Yang
- State Key Laboratory of Polymer Physics and ChemistryChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China
- School of Applied Chemistry and EngineeringUniversity of Science and Technology of ChinaHefei230026China
| | - Wantao Zheng
- State Key Laboratory of Polymer Physics and ChemistryChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China
- School of Applied Chemistry and EngineeringUniversity of Science and Technology of ChinaHefei230026China
| | - Dehua Hu
- State Key Laboratory of Luminescent Materials and DevicesSouth China University of TechnologyGuangzhou510640China
| | - Feng Zhu
- State Key Laboratory of Polymer Physics and ChemistryChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China
- School of Applied Chemistry and EngineeringUniversity of Science and Technology of ChinaHefei230026China
| | - Yuguang Ma
- State Key Laboratory of Luminescent Materials and DevicesSouth China University of TechnologyGuangzhou510640China
| | - Donghang Yan
- State Key Laboratory of Polymer Physics and ChemistryChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China
- School of Applied Chemistry and EngineeringUniversity of Science and Technology of ChinaHefei230026China
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5
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Tang Z, Pi C, Wu Y, Cui X. Rhodium-Catalyzed Tandem Acylmethylation/Annulation Reactions of 2-Aryl-2 H-indazoles with Sulfoxonium Ylides: Easy Access to 6-Arylindazolo[2,3- a]quinolines. CHINESE J ORG CHEM 2023. [DOI: 10.6023/cjoc202206052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/22/2023]
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6
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An Insight into the Polymerization Process of the Selected Carbazole Derivatives - Why does It not always Lead to a Polymer Formation? Electrochim Acta 2022. [DOI: 10.1016/j.electacta.2022.140948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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7
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Konidena RK, Justin Thomas KR, Park JW. Recent Advances in the Design of Multi‐Substituted Carbazoles for Optoelectronics: Synthesis and Structure‐Property Outlook. CHEMPHOTOCHEM 2022. [DOI: 10.1002/cptc.202200059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
| | - K R Justin Thomas
- Indian Institute of Technology Roorkee Department of Chemistry Haridwar Road 247667 Roorkee INDIA
| | - Jong Wook Park
- Kyunghee University College of Engineering Chemical Engineering INDIA
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Konidena RK, Oh S, Kang S, Park SS, Lee H, Park J. Indolo[3,2,1- jk]carbazole-Derived Narrowband Violet-Blue Fluorophores: Tuning the Optical and Electroluminescence Properties by Chromophore Juggling. J Org Chem 2022; 87:6668-6679. [PMID: 35512315 DOI: 10.1021/acs.joc.2c00322] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The development of rigid polyaromatic building blocks for narrowband violet fluorophores has received tremendous attention. Herein, we designed and synthesized two new triangle-shaped rigid building blocks, namely, 2,5-di-tert-butylindolo[3,2,1-jk]carbazole (tBuICz) and 2,11-di-tert-butylindolo[3,2,1-jk]carbazole-4-carbonitrile (tBuICzCN), and tethered them with different chromophores to yield a series of violet-blue fluorophores, viz., ICzTPA-ICzPICN, and studied their structure-function relationship. The appended chromophores and cyano unit played a vital role in controlling the optical and electrical properties of the compounds. Except triphenylamine-substituted derivatives, the compounds showed pure violet emission (λem ≤ 403 nm). Intriguingly, the compounds exhibited narrow-band emission with a full-width at half-maximum ≤ 40 nm, attributed to the rigidity of the ICz core. The emission of the compounds displayed positive solvatochromism, which is ascribed to the photoinduced intramolecular charge transfer in the excited state. The compounds revealed excellent thermal robustness with T5d ≥ 363 °C. The triphenylamine-featuring derivatives displayed a high-lying HOMO compared to their congeners due to their electron-rich nature. When we applied these materials in organic light-emitting diodes, ICzPI outperformed in the series with an EQEmax of 3.07% and a current efficiency of 1.04 cd/A. Notably, its CIEy ∼ 0.046 precisely matched with the Rec.2020 standard of deep-blue color (CIEy ∼ 0.046).
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Affiliation(s)
| | - Seyoung Oh
- Department of Chemical Engineering, Kyunghee University, Suwon 17104, Republic of Korea
| | - Seokwoo Kang
- Department of Chemical Engineering, Kyunghee University, Suwon 17104, Republic of Korea
| | - Sang-Shin Park
- Department of Chemical Engineering, Kyunghee University, Suwon 17104, Republic of Korea
| | - Hayoon Lee
- Department of Chemical Engineering, Kyunghee University, Suwon 17104, Republic of Korea
| | - Jongwook Park
- Department of Chemical Engineering, Kyunghee University, Suwon 17104, Republic of Korea
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9
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Li G, Li B, Zhang H, Guo X, Lin C, Chen K, Wang Z, Ma D, Tang BZ. Efficient Ultraviolet Organic Light-Emitting Diodes with a CIEy of 0.04 and Negligible-Efficiency Roll-Off. ACS APPLIED MATERIALS & INTERFACES 2022; 14:10627-10636. [PMID: 35171553 DOI: 10.1021/acsami.1c24285] [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
Organic light-emitting diodes (OLEDs) with ultraviolet (UV) emission (λEL ≤ 400 nm) have attracted special attention in commercial and civil fields owing to their special functions. Nevertheless, the lack of high-quality ultraviolet emitters restricts the practical application of UV OLEDs. Herein, a novel organic molecule with desirable UV emission, 2Na-CzCN, is developed for UV OLEDs. Theoretical investigation indicates that it is equipped with hybridized local and charge-transfer (HLCT) characteristics, which is in favor of the high-lying reverse intersystem crossing (RISC) process, thus remarkably boosting the exciton utilization in electroluminescence (EL). Significantly, the nondoped device derived from the 2Na-CzCN emitter exhibits an EL emission peak of 398 nm with a maximum external quantum efficiency (EQE) of 5.92%, which represents the record-high result among nondoped UV OLEDs. The doped UV OLED of 2Na-CzCN radiates robust UV emission at a peak of 392 nm with a maximum EQE of 6.15%. Coupled with the narrow full width at half-maximum (FWHM) of the EL spectra, desirable color purities with Commission Internationale de l'Eclairage (CIE) coordinates of (0.15, 0.06) and (0.16, 0.04) for nondoped and doped OLEDs are presented, respectively. Additionally, the potential of 2Na-CzCN adopted as the host material is demonstrated with phosphorescent OLEDs (PhOLEDs), and all of the devices show good EL performances with low-efficiency roll-offs. An orange PhOLED with 2Na-CzCN acquires a maximum current and external quantum efficiency of 84.9 cd A-1 and 25.3%, respectively. These findings may pave an avenue for the development of high-performance UV emitters.
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Affiliation(s)
- Ganggang Li
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, Center for Aggregation-Induced Emission, AIE Institute, Guangzhou International Campus, South China University of Technology, Guangzhou 510640, China
| | - Baoxi Li
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, Center for Aggregation-Induced Emission, AIE Institute, Guangzhou International Campus, South China University of Technology, Guangzhou 510640, China
| | - Han Zhang
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, Center for Aggregation-Induced Emission, AIE Institute, Guangzhou International Campus, South China University of Technology, Guangzhou 510640, China
| | - Xuecheng Guo
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, Center for Aggregation-Induced Emission, AIE Institute, Guangzhou International Campus, South China University of Technology, Guangzhou 510640, China
| | - Chengwei Lin
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, Center for Aggregation-Induced Emission, AIE Institute, Guangzhou International Campus, South China University of Technology, Guangzhou 510640, China
| | - Kongqi Chen
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, Center for Aggregation-Induced Emission, AIE Institute, Guangzhou International Campus, South China University of Technology, Guangzhou 510640, China
| | - Zhiming Wang
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, Center for Aggregation-Induced Emission, AIE Institute, Guangzhou International Campus, South China University of Technology, Guangzhou 510640, China
| | - Dongge Ma
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, Center for Aggregation-Induced Emission, AIE Institute, Guangzhou International Campus, South China University of Technology, Guangzhou 510640, China
| | - Ben Zhong Tang
- Shenzhen Institute of Aggregate Science and Technology, School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Shenzhen 518172, China
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Girase JD, Kajjam AB, Dubey DK, Kishore Kesavan K, Jou JH, Vaidyanathan S. Unipolar 1-phenylimidazo[1,5-a]pyridine: A new class of ultra-bright sky blue emitters for solution-processed organic light emitting diodes. NEW J CHEM 2022. [DOI: 10.1039/d2nj01938h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Three fluorophores based on Imidazo[1,5-a]pyridine (ImPy) decorated with aromatic π-system (C3 position of ImPy is decorated with naphthalene, methoxy-naphthalene and pyrene) were designed and synthesized by one-pot synthesis method. The...
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11
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Sun G, Wang XH, Li J, Yang BT, Gao Y, Geng Y. Effect of hybridized local and charge transfer molecules rotation in excited state on exciton utilization. Sci Rep 2021; 11:17686. [PMID: 34480055 PMCID: PMC8417272 DOI: 10.1038/s41598-021-97229-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 08/23/2021] [Indexed: 11/09/2022] Open
Abstract
The fluorescent molecules utilizing hybridized local and charge-transfer (HLCT) state as potential organic light-emitting diodes materials attract extensive attention due to their high exciton utilization. In this work, we have performed the density functional theory method on three HLCT-state molecules to investigate their excited-state potential energy surface (PES). The calculated results indicate the T1 and T2 energy gap is quite large, and the T2 is very close to S1 in the energy level. The large gap is beneficial for inhibiting the internal conversion between T1 and T2, and quite closed S1 and T2 energies are favor for activating the T2 → S1 reverse intersystem crossing path. However, considering the singlet excited-state PES by twisting the triphenylamine (TPA) or diphenylamine (PA) group, it can be found that the TPA or PA group almost has no influence on T1 and T2 energy levels. However, the plots of S1 PES display two kinds of results that the S1 emissive state is dominated by charge-transfer (CT) or HLCT state. The CT emission state formation would decrease the S1 energy level, enlarge the S1 and T2 gap, and impair the triplet exciton utilization. Therefore, understanding the relationship between the S1 PES and molecular structures is important for designing high-performance luminescent materials utilizing HLCT state.
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Affiliation(s)
- Gang Sun
- College of Science, Beihua University, Jilin, 132013, People's Republic of China
| | - Xin-Hui Wang
- College of Science, Beihua University, Jilin, 132013, People's Republic of China
| | - Jing Li
- College of Science, Beihua University, Jilin, 132013, People's Republic of China
| | - Bo-Ting Yang
- College of Science, Beihua University, Jilin, 132013, People's Republic of China.
| | - Ying Gao
- Jilin Provincial Key Laboratory of Straw-Based Functional Materials, Institute for Interdisciplinary Biomass Functional Materials Studies, Jilin Engineering Normal University, Changchun, 130052, People's Republic of China.
| | - Yun Geng
- Faculty of Chemistry, Northeast Normal University, Changchun, 130024, People's Republic of China
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Matiadis D, Nowak KE, Alexandratou E, Hatzidimitriou A, Sagnou M, Papadakis R. Synthesis and (fluoro)solvatochromism of two 3-styryl-2-pyrazoline derivatives bearing benzoic acid moiety: A spectral, crystallographic and computational study. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.115737] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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13
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Kumar K, Kesavan KK, Thakur D, Banik S, Jayakumar J, Cheng CH, Jou JH, Ghosh S. Functional Pyrene-Pyridine-Integrated Hole-Transporting Materials for Solution-Processed OLEDs with Reduced Efficiency Roll-Off. ACS OMEGA 2021; 6:10515-10526. [PMID: 34056206 PMCID: PMC8153793 DOI: 10.1021/acsomega.0c04080] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 12/15/2020] [Indexed: 06/12/2023]
Abstract
A series of new functional pyridine-appended pyrene derivatives, viz., 2,6-diphenyl-4-(pyren-1-yl)pyridine (Py-03), 2,6-bis(4-methoxyphenyl)-4-(pyren-1-yl)pyridine (Py-MeO), 4-(pyren-1-yl)-2,6-di-p-tolylpyridine (Py-Me), and 2,6-bis(4-bromophenyl)-4-(pyren-1-yl)pyridine (Py-Br) were designed, developed, and studied as the hole-transporting materials (HTMs) for organic light-emitting diode (OLED) application. The crystal structures of two molecules revealed to have a large dihedral angle between the pyrene and pyridine units, indicating poor π-electronic communication between them due to ineffective orbital overlap across the pyrene-pyridine systems as the two p-orbitals of pivotal atoms are twisted at 66.80° and 68.75° angles to each other in Py-03 and Py-Me, respectively. The influence of variedly functionalized pyridine units on the electro-optical properties and device performance of the present integrated system for OLED application was investigated. All of the materials have suitable HOMO values (5.6 eV) for hole injection by closely matching the HOMOs of indium tin oxide (ITO) and the light-emitting layer. All of the synthesized molecules have suitable triplet energies, glass transition temperatures, and melting temperatures, which are highly desirable for good HTMs. The pyrene-pyridine-based devices demonstrated stable performance with low-efficiency roll-off. The device with Py-Br as HTM showed a maximum luminance of 17300 cd/m2 with a maximum current efficiency of 22.4 cd/A and an EQE of 9% at 3500 cd/m2 with 7% roll-off from 1000 to 10 000 cd/m2. Also, the devices with Py-Me and Py-03 showed performance roll-up while moving from 1000 to 10 000 cd/m2.
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Affiliation(s)
- Krishan Kumar
- School
of Basic Sciences, IIT Mandi, Mandi, Himachal Pradesh 175005, India
| | - Kiran Kishore Kesavan
- Department
of Materials Science and Engineering, National
Tsing Hua University, 101, Sec. 2, Guang-Fu Road, Hsinchu 30013, Taiwan, R.O.C.
| | - Diksha Thakur
- School
of Basic Sciences, IIT Mandi, Mandi, Himachal Pradesh 175005, India
| | - Subrata Banik
- Department
of Chemistry, School of Chemical and Biotechnology, SASTRA Deemed University, Thanjavur 613401, Tamil Nadu, India
| | | | - Chien-Hong Cheng
- Department
of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan, R.O.C.
| | - Jwo-Huei Jou
- Department
of Materials Science and Engineering, National
Tsing Hua University, 101, Sec. 2, Guang-Fu Road, Hsinchu 30013, Taiwan, R.O.C.
| | - Subrata Ghosh
- School
of Basic Sciences, IIT Mandi, Mandi, Himachal Pradesh 175005, India
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14
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Xu Y, Xu P, Hu D, Ma Y. Recent progress in hot exciton materials for organic light-emitting diodes. Chem Soc Rev 2020; 50:1030-1069. [PMID: 33231588 DOI: 10.1039/d0cs00391c] [Citation(s) in RCA: 139] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
According to Kasha's rule, high-lying excited states usually have little effect on fluorescence. However, in some molecular systems, the high-lying excited states partly or even mainly contribute to the photophysical properties, especially in the process of harvesting triplet excitons in organic electroluminescent devices. In the current review, we focus on a type of organic light-emitting diode (OLED) materials called "hot exciton" materials, which can effectively harness the non-radiative triplet excitons via reverse intersystem crossing (RISC) from high-lying triplet states to singlet states (Tn→ Sm; n≥ 2, m≥ 1). Since Ma and Yang proposed the hot exciton mechanism for OLED material design in 2012, there have been many reports aiming at the design and synthesis of novel hot exciton luminogens. Herein, we present a comprehensive review of the recent progress in hot exciton materials. The developments of the hot exciton mechanism are reviewed, the fundamental principles regarding molecular design are discussed, and representative reported hot exciton luminogens are summarized and analyzed, along with their structure-property relationships and OLED applications.
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Affiliation(s)
- Yuwei Xu
- 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.
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15
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Konidena RK, Thomas KRJ, Dubey DK, Sahoo S, Jou J. Fine‐Tuning the Physicochemical and Electroluminescence Properties of Multiply‐Substituted Bipolar Carbazoles by Functional Group Juggling. CHEMPHOTOCHEM 2020. [DOI: 10.1002/cptc.202000172] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Rajendra Kumar Konidena
- Organic Materials Laboratory Department of Chemistry Indian Institute of Technology Roorkee Roorkee 247 667 India
| | - K. R. Justin Thomas
- Organic Materials Laboratory Department of Chemistry Indian Institute of Technology Roorkee Roorkee 247 667 India
| | - Deepak Kumar Dubey
- Department of Material Science and Engineering National Tsing Hua University Hsinchu 30013 Taiwan
| | - Snehasis Sahoo
- Department of Material Science and Engineering National Tsing Hua University Hsinchu 30013 Taiwan
| | - Jwo‐Huei Jou
- Department of Material Science and Engineering National Tsing Hua University Hsinchu 30013 Taiwan
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16
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Konidena RK, Chung WJ, Lee JY. C1-, C2-, and C3-Modified Carbazole Derivatives as Promising Host Materials for Phosphorescent Organic Light-Emitting Diodes. Org Lett 2020; 22:2786-2790. [DOI: 10.1021/acs.orglett.0c00767] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Rajendra Kumar Konidena
- School of Chemical Engineering, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Suwon, Gyeonggi 440-746, Korea
| | - Won Jae Chung
- School of Chemical Engineering, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Suwon, Gyeonggi 440-746, Korea
| | - Jun Yeob Lee
- School of Chemical Engineering, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Suwon, Gyeonggi 440-746, Korea
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17
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Jayabharathi J, Panimozhi S, Thanikachalam V. A novel hot exciton blue fluorophores and white organic light-emitting diodes with simplified configuration. Sci Rep 2020; 10:5114. [PMID: 32198377 PMCID: PMC7083847 DOI: 10.1038/s41598-020-62029-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 01/13/2020] [Indexed: 12/03/2022] Open
Abstract
The two efficient non-doped blue emitters with hybridized local and charge transfer state namely, NDBNPIN and DBTPIN have been synthesised and characterised. These materials are employed as a host for green and red phosphorescent OLEDs. The white device based on DBTPIN:Ir(MDQ)2(acac) (4%) exhibit maximum external quantum efficiency (ηex) -24.8%; current efficiency (ηc) -57.1 cdA-1; power efficiency (ηp) -64.8 lmW-1 with Commission Internationale de l'Eclairage (CIE:0.49, 0.40) than NDBNPIN:Ir(MDQ)2acac (4%) device [ηex - 23.1%; ηc -54.6 cd A-1; ηp- 60.0 lm W-1 with CIE (0.47, 0.42)].
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Affiliation(s)
- Jayaraman Jayabharathi
- Department of Chemistry, Annamalai University, Annamalainagar, 608 002, Tamilnadu, India.
| | - Sekar Panimozhi
- Department of Chemistry, Annamalai University, Annamalainagar, 608 002, Tamilnadu, India
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Thiyagarajan MD, Balijapalli U, Nasiri S, Volyniuk D, Simokaitienec J, Pathak M, Iyer SK, Gražulevičius JV. Rational Synthesis of Tetrahydrodibenzophenanthridine and Phenanthroimidazole as Efficient Blue Emitters and their Applications. European J Org Chem 2020. [DOI: 10.1002/ejoc.201901711] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
| | - Umamahesh Balijapalli
- Department of Chemistry; School of Advanced Sciences; Vellore Institute of Technology; 632014 Vellore Tamilnadu India
- Centre for Organic Photonics and Electronics Research (OPERA); Kyushu University; 744 Motooka, Nishi 819-0395 Fukuoka Japan
| | - Sohrab Nasiri
- Kaunas University of Technology; Department of Polymer Chemistry and Technology; Radvilenu pl.19, LT 50254 Kaunas Lithunania
| | - Dmytro Volyniuk
- Kaunas University of Technology; Department of Polymer Chemistry and Technology; Radvilenu pl.19, LT 50254 Kaunas Lithunania
| | - Jurate Simokaitienec
- Kaunas University of Technology; Department of Polymer Chemistry and Technology; Radvilenu pl.19, LT 50254 Kaunas Lithunania
| | - Madhvesh Pathak
- Department of Chemistry; School of Advanced Sciences; Vellore Institute of Technology; 632014 Vellore Tamilnadu India
| | - Sathiyanarayanan Kulathu Iyer
- Department of Chemistry; School of Advanced Sciences; Vellore Institute of Technology; 632014 Vellore Tamilnadu India
| | - Juozas Vidas Gražulevičius
- Kaunas University of Technology; Department of Polymer Chemistry and Technology; Radvilenu pl.19, LT 50254 Kaunas Lithunania
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19
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Fe3O4@zeolite-SO3H as a magnetically bifunctional and retrievable nanocatalyst for green synthesis of perimidines. RESEARCH ON CHEMICAL INTERMEDIATES 2019. [DOI: 10.1007/s11164-019-03992-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Konidena RK, Lee KH, Lee JY, Hong WP. Triggering Thermally Activated Delayed Fluorescence by Managing the Heteroatom in Donor Scaffolds: Intriguing Photophysical and Electroluminescence Properties. Chem Asian J 2019; 14:2251-2258. [PMID: 30969458 DOI: 10.1002/asia.201900388] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Revised: 04/09/2019] [Indexed: 02/06/2023]
Abstract
Establishment of the structure-property relationships of thermally activated delayed fluorescence (TADF) materials has become a significant quest for the scientific community. Herein, two new donors, 10H-benzofuro[3,2-b]indole (BFI) and 10H-benzo[4,5]thieno[3,2-b]indole (BTI), have been developed and integrated with a aryltriazine acceptor to design the green TADF emitters benzofuro[3,2-b]indol-10-yl)-5-(4,6-diphenyl-1,3,5-triazin-2-yl)benzonitrile (BFICNTrz) and 2-(10H-benzo[4,5]thieno[3,2-b]indol-10-yl)-5-(4,6-diphenyl-1,3,5-triazin-2-yl)benzonitrile (BTICNTrz), respectively. The physicochemical and electroluminescence properties of the compounds were tuned by exchanging the heteroatom in the donor scaffold. Intriguingly, the electronegativity of the heteroatom and the ionization potential of the donor unit played vital roles in control of the singlet-triplet energy splitting and TADF mechanism of the compounds. Both compounds showed similar singlet excited states that originated from the charge transfer (CT) states (1 CT), whereas the triplet excited states were tuned by the heteroatom in the donor unit. The origin of phosphorescence in the BTICNTrz emitter was CT emission from the triplet state (3 CT), whereas that in the BFICNTrz emitter stemmed from the local triplet excited state (3 LE). Consequently, BTICNTrz showed a small singlet-triplet energy splitting of 0.08 eV, compared with 0.26 eV for BFICNTrz. Thus, BTICNTrz showed efficient delayed fluorescence with a high quantum yield and a short delayed exciton lifetime, whereas BFICNTrz displayed weak delayed fluorescence with a relatively long lifetime. Furthermore, a BTICNTrz-based device exhibited a maximum external quantum efficiency (EQE) of 15.2 % and reduced efficiency roll-off (12 %) compared with its BFICNTrz-based counterpart, which showed a maximum EQE of 6.4 % and severe efficiency roll-off (55 %) at a practical brightness range of 1000 cd m-2 . These results demonstrate that the choice of subunit plays a vital role in the design of efficient TADF emitters.
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Affiliation(s)
- Rajendra Kumar Konidena
- School of Chemical Engineering, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Suwon, Gyeonggi, 440-746, Korea
| | - Kyung Hyung Lee
- School of Chemical Engineering, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Suwon, Gyeonggi, 440-746, Korea
| | - Jun Yeob Lee
- School of Chemical Engineering, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Suwon, Gyeonggi, 440-746, Korea
| | - Wan Pyo Hong
- LG Chem, Ltd, LG Science Park, 30, Magokjungang 10-ro, Gangseo-gu, Seoul, 07796, Republic of Korea
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21
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Tagare J, Dubey DK, Jou J, Vaidyanathan S. Near UV/Deep‐Blue Phenanthroimidazole‐Based Luminophores for Organic Light‐Emitting Diodes: Experimental and Theoretical Investigation. ChemistrySelect 2019. [DOI: 10.1002/slct.201900383] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Jairam Tagare
- Optoelectronics laboratoryDepartment of ChemistryNational Institute of Technology Rourkela India
| | - Deepak Kumar Dubey
- Department of Materials Science and EngineeringNational Tsing Hua University Hsinchu Taiwan- 30013
| | - Jwo‐Huei Jou
- Department of Materials Science and EngineeringNational Tsing Hua University Hsinchu Taiwan- 30013
| | - Sivakumar Vaidyanathan
- Optoelectronics laboratoryDepartment of ChemistryNational Institute of Technology Rourkela India
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22
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Ansari AJ, Joshi G, Sharma P, Maurya AK, Metre RK, Agnihotri VK, Chandaluri CG, Kumar R, Singh S, Sawant DM. Pd-Catalyzed Four-Component Sequential Reaction Delivers a Modular Fluorophore Platform for Cell Imaging. J Org Chem 2019; 84:3817-3825. [DOI: 10.1021/acs.joc.8b02845] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Arshad J. Ansari
- School of Chemical Sciences and Pharmacy, Central University of Rajasthan NH-8, Bandarsindri, Ajmer 305817, India
| | - Gaurav Joshi
- Laboratory for Drug Design and Synthesis, Department of Pharmaceutical Sciences and Natural Products, Central University of Punjab, Bathinda, Punjab 151001, India
| | - Praveen Sharma
- Laboratory of Molecular Medicine, Department of Human Genetics and Molecular Medicine, Central University of Punjab, Bathinda, Punjab 151001, India
| | - Antim K. Maurya
- Natural Product Chemistry and Process Development Division, CSIR-IHBT, Palampur, Himachal Pradesh 176061, India
| | - Ramesh K. Metre
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwad, Jodhpur, Rajasthan 342037, India
| | - Vijai K. Agnihotri
- Natural Product Chemistry and Process Development Division, CSIR-IHBT, Palampur, Himachal Pradesh 176061, India
| | - Chanchayya Gupta Chandaluri
- School of Chemical Sciences and Pharmacy, Central University of Rajasthan NH-8, Bandarsindri, Ajmer 305817, India
| | - Raj Kumar
- Laboratory for Drug Design and Synthesis, Department of Pharmaceutical Sciences and Natural Products, Central University of Punjab, Bathinda, Punjab 151001, India
| | - Sandeep Singh
- Laboratory of Molecular Medicine, Department of Human Genetics and Molecular Medicine, Central University of Punjab, Bathinda, Punjab 151001, India
| | - Devesh M. Sawant
- School of Chemical Sciences and Pharmacy, Central University of Rajasthan NH-8, Bandarsindri, Ajmer 305817, India
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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 APPLIED MATERIALS & 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] [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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Song H, Wang K, Kuang Z, Zhao YS, Guo Q, Xia A. Solvent modulated excited state processes of push-pull molecule with hybridized local excitation and intramolecular charge transfer character. Phys Chem Chem Phys 2019; 21:3894-3902. [PMID: 30702103 DOI: 10.1039/c8cp06459h] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Recently, a type of synthetic highly efficient OLED molecule based on a hybridized local excitation and charge transfer (HLCT) character has received much attention as a potential high-efficiency fluorescent OLED material. In this article, we report the relaxation dynamics of the excited states of cyano-substituted oligo α-phenylenevinylene-1,4-bis(R-cyano-4-diphenylaminostyryl)-2,5-diphenylbenzene (CNDPASDB) with HLCT character using steady-state and time-resolved spectroscopy as well as quantum chemical calculations. The dramatic dependence of the fluorescence quantum yield, radiative and non-radiative rate, as well as the excited state relaxation pathways on solvent polarity reveals that the solvation process controls the energy levels of two closely spaced electronic excited states. By employing femtosecond transient absorption spectra, the gradual transition from the LE state to the intramolecular CT state with an increase in solvent polarity is clearly resolved. In low-polarity solvents the fluorescence of CNDPASDB is mainly emission from the LE state, whereas in high-polarity solvents non-radiative decay from the CT state dominates. And in medium-polarity solvents, because of the relatively weaker solvation-induced stabilization of the CT state, its energy could be equal to or slightly lower than that of the LE state, leading to a smaller driving force for LE → CT interconversion; therefore complete LE → CT interconversion cannot take place. In this situation, LE ↔ CT intercrossed equilibration is established and the equilibrium constant is further estimated to be about 4 according to the obtained kinetics, and the equilibrium population of the CT state is about 80%. DFT/TDDFT analysis also confirmed an efficient intercrossing of LE and CT states with an increase in solvent polarity. It is found that upon increasing the solvent polarity, the hole and electron on a molecule are entirely separated, suggesting a complete CT character. These results provide guidance for understanding the relationship between solvent polarity and the HLCT process, as well as for designing and synthesizing advanced OLED materials.
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Affiliation(s)
- Hongwei Song
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
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Kwak SW, Jin H, Lee JH, Hwang H, Kim M, Kim Y, Chung Y, Lee KM, Park MH. Systematic Control of the Overlapping Energy Region for an Efficient Intramolecular Energy Transfer: Functionalized Salen–Al/Triphenylamine Guest–Host Assemblies. Inorg Chem 2019; 58:2454-2462. [DOI: 10.1021/acs.inorgchem.8b03005] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Hyomin Jin
- Department of Chemistry and Institute for Molecular Science and Fusion Technology, Kangwon National University, Chuncheon, Gangwon 24341, Republic of Korea
| | - Ji Hye Lee
- Department of Chemistry and Institute for Molecular Science and Fusion Technology, Kangwon National University, Chuncheon, Gangwon 24341, Republic of Korea
| | - Hyonseok Hwang
- Department of Chemistry and Institute for Molecular Science and Fusion Technology, Kangwon National University, Chuncheon, Gangwon 24341, Republic of Korea
| | | | | | | | - Kang Mun Lee
- Department of Chemistry and Institute for Molecular Science and Fusion Technology, Kangwon National University, Chuncheon, Gangwon 24341, Republic of Korea
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Chen F, Zhang W, Liu Z, Meng L, Bai B, Wang H, Li M. Enhancement of intramolecular charge transfer strength in diphenylamine substituted symmetric 1,3,4-oxadiazole derivatives. RSC Adv 2018; 9:1-10. [PMID: 35521585 PMCID: PMC9059167 DOI: 10.1039/c8ra08439d] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 12/10/2018] [Indexed: 01/21/2023] Open
Abstract
The intramolecular charge transfer characteristic of two diphenylamine substituted symmetric 1,3,4-oxadiazole derivatives (DPAOXD and DPAOXDBEN) was studied through a combination of experimental techniques and theoretical calculations. Significant enhancement of intramolecular charge transfer strength has been found in both these compounds through molecular structure modification. The experimental result found only a small red shift in the absorption spectra (∼15 nm) but a very large red shift in the emission spectra (∼114 nm for DPAOXD and ∼140 nm for DPAOXDBEN) with increasing solvent polarity, indicating a large extent charge transfer occurred in their excited state. The increase of molecular dipole moment from the ground state to the charge transfer excited state is calculated to be 22.10 D in DPAOXD and 26.67 D in DPAOXDBEN, respectively. Theoretical calculations present clear evidence that electrons transfer from the terminal diphenylamine to the bi-1,3,4-oxadiazole rings in DPAOXD, and the two 1,3,4-oxadiazole rings and central benzene ring in DPAOXDBEN. As compared to the methoxy group, the substitution by a diphenylamine group could increase both the transferred charge and distance, which could substantially strengthen the charge transfer character. Further introduction of a central benzene ring in DPAOXDBEN could further increase the transferred distance, and then the charge transfer strength. These findings could provide good guidance for the design of molecules with high intramolecular charge transfer characteristics.
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Affiliation(s)
- Fangyi Chen
- Key Laboratory of Automobile Materials (MOE), College of Materials Science and Engineering, Jilin University Changchun 130012 China
| | - Wanxi Zhang
- Key Laboratory of Automobile Materials (MOE), College of Materials Science and Engineering, Jilin University Changchun 130012 China
| | - Zijian Liu
- Key Laboratory of Automobile Materials (MOE), College of Materials Science and Engineering, Jilin University Changchun 130012 China
| | - Lingyan Meng
- Key Laboratory of Automobile Materials (MOE), College of Materials Science and Engineering, Jilin University Changchun 130012 China
| | - Binglian Bai
- College of Physics, Jilin University Changchun 130012 China
| | - Haitao Wang
- Key Laboratory of Automobile Materials (MOE), College of Materials Science and Engineering, Jilin University Changchun 130012 China
| | - Min Li
- Key Laboratory of Automobile Materials (MOE), College of Materials Science and Engineering, Jilin University Changchun 130012 China
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Konidena RK, Lee JY. Molecular Design Tactics for Highly Efficient Thermally Activated Delayed Fluorescence Emitters for Organic Light Emitting Diodes. CHEM REC 2018; 19:1499-1517. [DOI: 10.1002/tcr.201800136] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 10/10/2018] [Indexed: 01/15/2023]
Affiliation(s)
- Rajendra Kumar Konidena
- School of Chemical EngineeringSungkyunkwan University 2066 Seobu-ro, Jangan-gu, Suwon Gyeonggi Korea
| | - Jun Yeob Lee
- School of Chemical EngineeringSungkyunkwan University 2066 Seobu-ro, Jangan-gu, Suwon Gyeonggi Korea
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28
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Bala I, Ming L, Yadav RAK, De J, Dubey DK, Kumar S, Singh H, Jou J, Kailasam K, Pal SK. Deep‐Blue OLED Fabrication from Heptazine Columnar Liquid Crystal Based AIE‐Active Sky‐Blue Emitter. ChemistrySelect 2018. [DOI: 10.1002/slct.201801715] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Indu Bala
- Department of Chemical SciencesIndian Institute of Science Education and Research (IISER), Mohali, Sector-81 Knowledge city Manauli 140306 India
| | - Lee Ming
- Department of Materials Science and EngineeringNational Tsing Hua University Hsinchu 30013 Taiwan
| | - Rohit Ashok Kumar Yadav
- Department of Materials Science and EngineeringNational Tsing Hua University Hsinchu 30013 Taiwan
| | - Joydip De
- Department of Chemical SciencesIndian Institute of Science Education and Research (IISER), Mohali, Sector-81 Knowledge city Manauli 140306 India
| | - Deepak Kumar Dubey
- Department of Materials Science and EngineeringNational Tsing Hua University Hsinchu 30013 Taiwan
| | - Sunil Kumar
- Institute of Nano Science and Technology (INST), Sector-64, Phase 10 Mohali 160062 India
| | - Harpreet Singh
- Department of Chemical SciencesIndian Institute of Science Education and Research (IISER), Mohali, Sector-81 Knowledge city Manauli 140306 India
| | - Jwo‐Huei Jou
- Department of Materials Science and EngineeringNational Tsing Hua University Hsinchu 30013 Taiwan
| | - Kamalakannan Kailasam
- Institute of Nano Science and Technology (INST), Sector-64, Phase 10 Mohali 160062 India
| | - Santanu Kumar Pal
- Department of Chemical SciencesIndian Institute of Science Education and Research (IISER), Mohali, Sector-81 Knowledge city Manauli 140306 India
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Konidena RK, Thomas KRJ, Pathak A, Dubey DK, Sahoo S, Jou JH. Tuning the Photophysical and Electroluminescence Properties in Asymmetrically Tetrasubstituted Bipolar Carbazoles by Functional Group Disposition. ACS APPLIED MATERIALS & INTERFACES 2018; 10:24013-24027. [PMID: 29931980 DOI: 10.1021/acsami.8b04566] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Carbazoles decorated with both donor and acceptor fragments offer a classical way to optimize bipolar functional properties. In this work, a series of carbazoles featuring triphenylamine donors and cyano acceptors are synthesized and their structure-property relationship is studied. The effects of connectivity and the chromophore number density on photophysical and electroluminescence properties are investigated. The position of the triphenylamine donor on the 3,6-dicyanocarbazole nucleus significantly affected the photophysical and electroluminescence properties. The dye possessing triphenylamine on C2 and C7 displayed a red shift in absorption when compared with the structural analogue with triphenylamine tethered to C1 and C8. The emission wavelength of the dyes are tunable from blue to green, by altering the position of triphenylamine and cyano substituents. All of the dyes exhibited positive solvatochromism in emission, attributable to the photoinduced intramolecular charge transfer from the triphenylamine donor to the cyano acceptor. However, the extent of charge transfer and hybridization of local and charge-transfer-excited states is highly dependent on the position of triphenylamine and cyano groups on the carbazole nucleus. Dyes containing cyano substituents at C2 and C7 showed a prolonged excited state lifetime, broad emission, and large Stokes shifts, indicating the presence of a higher charge transfer component in the excited state. The dyes displayed exceptional thermal stability with the onset decomposition temperature (10% weight loss) > 350 °C. Electrochemical measurements revealed low oxidation potential for dyes containing triphenylamine at C3 and/or C6. Addition of a cyano acceptor on carbazole led to the stabilization of lowest unoccupied molecular orbital. Furthermore, the materials were tested as emitting dopants in solution-processable multilayer organic light emitting diodes and found to display deep-blue/sky-blue electroluminescence with external quantum efficiency as high as 6.5% for a deep-blue emitter (CIE y ∼ 0.06).
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Affiliation(s)
- Rajendra Kumar Konidena
- Organic Materials Laboratory, Department of Chemistry , Indian Institute of Technology Roorkee , Roorkee 247 667 , India
| | - K R Justin Thomas
- Organic Materials Laboratory, Department of Chemistry , Indian Institute of Technology Roorkee , Roorkee 247 667 , India
| | - Ambika Pathak
- Organic Materials Laboratory, Department of Chemistry , Indian Institute of Technology Roorkee , Roorkee 247 667 , India
| | - Deepak Kumar Dubey
- Department of Material Science and Engineering , National Tsing Hua University , Hsinchu 30013 , Taiwan
| | - Snehasis Sahoo
- Department of Material Science and Engineering , National Tsing Hua University , Hsinchu 30013 , Taiwan
| | - Jwo-Huei Jou
- Department of Material Science and Engineering , National Tsing Hua University , Hsinchu 30013 , Taiwan
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Joseph V, Justin Thomas KR, Yang WY, Kumar Yadav RA, Kumar Dubey D, Jou JH. Tetra-substituted Dipolar Carbazoles: Tuning Optical and Electroluminescence Properties by Linkage Variation. ASIAN J ORG CHEM 2018. [DOI: 10.1002/ajoc.201800248] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Vellaichamy Joseph
- Organic Materials Laboratory; Department of Chemistry; Indian Institute of Technology Roorkee; Roorkee 247 667 India
| | - K. R. Justin Thomas
- Organic Materials Laboratory; Department of Chemistry; Indian Institute of Technology Roorkee; Roorkee 247 667 India
| | - Wan Yun Yang
- Department of Materials science and engineering; National Tsing Hua University; Hsinchu 30013 Taiwan
| | - 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
| | - Jwo-Huei Jou
- Department of Materials science and engineering; National Tsing Hua University; Hsinchu 30013 Taiwan
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31
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Peng S, Zhao Y, Fu C, Pu X, Zhou L, Huang Y, Lu Z. Acquiring High-Performance Deep-Blue OLED Emitters through an Unexpected Blueshift Color-Tuning Effect Induced by Electron-Donating -OMe Substituents. Chemistry 2018; 24:8056-8060. [PMID: 29655182 DOI: 10.1002/chem.201800974] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 04/05/2018] [Indexed: 11/11/2022]
Abstract
A series of blue-emissive 7-(diphenylamino)-4-phenoxycoumarin derivatives bearing -CF3 , -OMe, or -N(Me)2 substituents on the phenoxy subunit were synthesized. Although both the -CF3 and -N(Me)2 modifications were found to trigger redshifted fluorescence, the -OMe substitution was demonstrated to exert an unexpected blueshift color-tuning effect toward the deep-blue region. The reason is that the moderate electron-donating -OMe group can endow coumarins with unaltered HOMO but elevated LUMO energy levels. Moreover, the -OMe substitution was found to be beneficial to the thermal stability of these coumarins. Therefore, the trimethoxy-substituted objective compound can act as a high-performance deep-blue organic light-emitting diode (OLED) emitter, and OLED based on it emits deep-blue light with CIE coordinates of (0.148, 0.084), maximum luminance of 7800 cd m-2 , and maximum external quantum efficiency of 5.1 %. These results not only shed light on the molecular design strategy for high-performance deep-blue OLED emitters through color-tuning, but also show the perspective of coumarin derivatives as deep-blue OLED emitters.
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Affiliation(s)
- Song Peng
- Key Laboratory of Green Chemistry and Technology (Ministry of, Education), College of Chemistry, Sichuan University, Chengdu, 610064, P.R. China
| | - Yihuan Zhao
- Key Laboratory of Green Chemistry and Technology (Ministry of, Education), College of Chemistry, Sichuan University, Chengdu, 610064, P.R. China
| | - Caixia Fu
- Key Laboratory of Green Chemistry and Technology (Ministry of, Education), College of Chemistry, Sichuan University, Chengdu, 610064, P.R. China
| | - Xuemei Pu
- Key Laboratory of Green Chemistry and Technology (Ministry of, Education), College of Chemistry, Sichuan University, Chengdu, 610064, P.R. China
| | - Liang Zhou
- State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, P.R. China
| | - Yan Huang
- Key Laboratory of Green Chemistry and Technology (Ministry of, Education), College of Chemistry, Sichuan University, Chengdu, 610064, P.R. China
| | - Zhiyun Lu
- Key Laboratory of Green Chemistry and Technology (Ministry of, Education), College of Chemistry, Sichuan University, Chengdu, 610064, P.R. China
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32
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Xie Y, Husband JT, Torrent-Sucarrat M, Yang H, Liu W, O’Reilly RK. Rational design of substituted maleimide dyes with tunable fluorescence and solvafluorochromism. Chem Commun (Camb) 2018; 54:3339-3342. [PMID: 29542762 PMCID: PMC5885783 DOI: 10.1039/c8cc00772a] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 03/08/2018] [Indexed: 12/14/2022]
Abstract
A series of maleimide derivatives were systematically designed and synthesized with tunable fluorescent properties. The facile modifications herein provide a simple methodology to expand the scope of maleimide-based dyes and also provide insight into the relationship between substitution pattern and optical properties.
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Affiliation(s)
- Yujie Xie
- Department of Chemistry, University of Warwick , Coventry , CV4 7AL , UK
| | | | - Miquel Torrent-Sucarrat
- Department of Organic Chemistry I , Universidad del País Vasco (UPV/EHU) , and Donostia International Physics Center (DIPC) , Manuel Lardizabal Ibilbidea 3 , Donostia 20018 , Spain
- Ikerbasque , Basque Foundation for Science , María Díaz de Haro 3, 6o̲ , Bilbao 48013 , Spain
| | - Huan Yang
- Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu Province and State Key Laboratory of Applied Organic Chemistry , Lanzhou University , Lanzhou 730000 , P. R. China
| | - Weisheng Liu
- Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu Province and State Key Laboratory of Applied Organic Chemistry , Lanzhou University , Lanzhou 730000 , P. R. China
| | - Rachel K. O’Reilly
- Department of Chemistry, University of Warwick , Coventry , CV4 7AL , UK
- School of Chemistry, University of Birmingham , Edgbaston , B15 2TT , UK .
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33
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Thermally Activated Delayed Fluorescence Emitters for Deep Blue Organic Light Emitting Diodes: A Review of Recent Advances. APPLIED SCIENCES-BASEL 2018. [DOI: 10.3390/app8040494] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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34
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Zhao J, Liu B, Wang Z, Tong Q, Du X, Zheng C, Lin H, Tao S, Zhang X. EQE Climbing Over 6% at High Brightness of 14350 cd/m 2 in Deep-Blue OLEDs Based on Hybridized Local and Charge-Transfer Fluorescence. ACS APPLIED MATERIALS & INTERFACES 2018; 10:9629-9637. [PMID: 29498275 DOI: 10.1021/acsami.7b19646] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Three deep-blue emitters PPi-Pid, PPi-Xid, and PPi-Mid based on a novel conjugated system phenantroimidazole-π-indolizine have been designed and synthesized. Here, indolizine with appropriate π-conjugation length was used as the acceptor profited from its high-photoluminescence quantum yield and good electron-withdrawing ability. Fluorescent organic light-emitting diodes (OLEDs) based on PPi-Pid, PPi-Xid, and PPi-Mid achieved deep-blue emissions with the Commission Internationale de L'Eclairage coordinates of (0.151, 0.076), (0.155, 0.052), and (0.153, 0.052); high brightness of 14350, 4377, and 4002 cd/m2; and high external quantum efficiencies (EQEs) of 6.01, 3.90, and 4.28%, respectively. Moreover, it is noticeable that all of the devices exhibited efficiencies increasing with brightness. In particular, the PPi-Pid-based device exhibited high EQE over 6% at a high brightness of 14350 cd/m2. Such high brightness along with high EQE is very rare whether in deep-blue fluorescent or thermally activated delayed fluorescent OLEDs.
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Affiliation(s)
- Juewen Zhao
- School of Optoelectronic Information , University of Electronic Science and Technology of China (UESTC) , Chengdu 610054 , P. R. China
| | - Bin Liu
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province , Shantou University , Shantou , Guangdong 515063 , P. R. China
| | - Zhongyi Wang
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province , Shantou University , Shantou , Guangdong 515063 , P. R. China
| | - Qingxiao Tong
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province , Shantou University , Shantou , Guangdong 515063 , P. R. China
| | - Xiaoyang Du
- School of Optoelectronic Information , University of Electronic Science and Technology of China (UESTC) , Chengdu 610054 , P. R. China
| | - Caijun Zheng
- School of Optoelectronic Information , University of Electronic Science and Technology of China (UESTC) , Chengdu 610054 , P. R. China
| | - Hui Lin
- School of Optoelectronic Information , University of Electronic Science and Technology of China (UESTC) , Chengdu 610054 , P. R. China
| | - Silu Tao
- School of Optoelectronic Information , University of Electronic Science and Technology of China (UESTC) , Chengdu 610054 , P. R. China
| | - Xiaohong Zhang
- Institute of Functional Nano & Soft Materials (FUNSOM) , Soochow University , Suzhou 215123 , P. R. China
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