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Brannan AC, Cho HH, Reponen APM, Gorgon S, Phuoc NL, Linnolahti M, Greenham NC, Romanov AS. Deep-Blue and Fast Delayed Fluorescence from Carbene-Metal-Amides for Highly Efficient and Stable Organic Light-Emitting Diodes. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2404357. [PMID: 38727713 DOI: 10.1002/adma.202404357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 05/06/2024] [Indexed: 05/21/2024]
Abstract
Linear gold complexes of the "carbene-metal-amide" (CMA) type are prepared with a rigid benzoguanidine amide donor and various carbene ligands. These complexes emit in the deep-blue range at 424 and 466 nm with 100% quantum yields in all media. The deep-blue thermally activates delayed fluorescence originates from a charge transfer state with an excited state lifetime as low as 213 ns, resulting in fast radiative rates of 4.7 × 106 s-1. The high thermal and photo-stability of these carbene-metal-amide (CMA) materials enabled the authors to fabricate highly energy-efficient organic light-emitting diodes (OLED) in host-guest architectures. Deep-blue OLED devices with electroluminescence at 416 and 457 nm with practical external quantum efficiencies of up to 23% at 100 cd m-2 with excellent color coordinates CIE (x; y) = 0.16; 0.07 and 0.17; 0.18 are reported. The operating stability of these OLEDs is the longest reported to date (LT50 = 1 h) for deep-blue CMA emitters, indicating a high promise for further development of blue OLED devices. These findings inform the molecular design strategy and correlation between delayed luminescence with high radiative rates and CMA OLED device operating stability.
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Affiliation(s)
- Alexander C Brannan
- Department of Chemistry, The University of Manchester, Oxford Rd, Manchester, M13 9PL, UK
| | - Hwan-Hee Cho
- Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Avenue, Cambridge, CB3 0HE, UK
| | - Antti-Pekka M Reponen
- Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Avenue, Cambridge, CB3 0HE, UK
| | - Sebastian Gorgon
- Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Avenue, Cambridge, CB3 0HE, UK
| | - Nguyen Le Phuoc
- Department of Chemistry, University of Eastern Finland, Joensuu, FI-80101, Finland
| | - Mikko Linnolahti
- Department of Chemistry, University of Eastern Finland, Joensuu, FI-80101, Finland
| | - Neil C Greenham
- Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Avenue, Cambridge, CB3 0HE, UK
| | - Alexander S Romanov
- Department of Chemistry, The University of Manchester, Oxford Rd, Manchester, M13 9PL, UK
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2
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Govindharaj P, Wierzba AJ, Kęska K, Kochman MA, Wiosna-Sałyga G, Kubas A, Data P, Lindner M. Regioisomerism vs Conformation: Impact of Molecular Design on the Emission Pathway in Organic Light-Emitting Device Emitters. ACS APPLIED MATERIALS & INTERFACES 2024; 16. [PMID: 38668584 PMCID: PMC11082840 DOI: 10.1021/acsami.3c19212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 04/14/2024] [Accepted: 04/17/2024] [Indexed: 05/12/2024]
Abstract
Despite the design and proposal of several new structural motifs as thermally activated delayed fluorescent (TADF) emitters for organic light-emitting device (OLED) applications, the nature of their interaction with the host matrix in the emissive layer of the device and their influence on observed photophysical outputs remain unclear. To address this issue, we present, for the first time, the use of up to four regioisomers bearing a donor-acceptor-donor electronic structure based on the desymmetrized naphthalene benzimidazole scaffold, equipped with various electron-donating units and possessing distinguished conformational lability. Quantum chemical calculations allow us to identify the most favorable conformations adopted by the electron-rich groups across the entire pool of regioisomers. These conformations were then compared with conformational changes caused by the interaction of the emitter with the Zeonex and 4,4'-bis(N-carbazolyl)-1,1'-biphenyl (CBP) matrices, and the correlation with observed photophysics was monitored by UV-vis absorption and steady-state photoluminescence spectra, combined with time-resolved spectroscopic techniques. Importantly, a CBP matrix was found to have a significant impact on the conformational change of regioisomers, leading to unique TADF emission mechanisms that encompass dual emission and inversion of the singlet-triplet excited-state energies and result in the enhancement of TADF efficiency. As a proof of concept, regioisomers with optimal donor positions were utilized to fabricate an OLED, revealing, with the best-performing dye, an external quantum emission of 11.6%, accompanied by remarkable luminance (28,000 cd/m2). These observations lay the groundwork for a better understanding of the role of the host matrix. In the long term, this new knowledge can lead to predicting the influence of the host matrix and adopting the structure of the emitter in a way that allows the development of highly efficient and efficient OLEDs.
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Affiliation(s)
- Prasannamani Govindharaj
- Department
of Molecular Physics, Faculty of Chemistry, Łódź University of Technology, Stefana Żeromskiego 114, 90-543 Łódź, Poland
| | - Aleksandra J. Wierzba
- Institute
of Organic Chemistry, Polish Academy of
Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Karolina Kęska
- Institute
of Organic Chemistry, Polish Academy of
Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Michał Andrzej Kochman
- Institute
of Physical Chemistry, Polish Academy of
Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Gabriela Wiosna-Sałyga
- Department
of Molecular Physics, Faculty of Chemistry, Łódź University of Technology, Stefana Żeromskiego 114, 90-543 Łódź, Poland
| | - Adam Kubas
- Institute
of Physical Chemistry, Polish Academy of
Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Przemysław Data
- Department
of Molecular Physics, Faculty of Chemistry, Łódź University of Technology, Stefana Żeromskiego 114, 90-543 Łódź, Poland
| | - Marcin Lindner
- Institute
of Organic Chemistry, Polish Academy of
Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
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3
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Posada Urrutia M, Dyrager C. Tuning the Emission Properties of 2,1,3-Benzothiadiazoles via Regioselective Substitution. Chemistry 2024:e202400644. [PMID: 38619336 DOI: 10.1002/chem.202400644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 04/13/2024] [Accepted: 04/15/2024] [Indexed: 04/16/2024]
Abstract
The 2,1,3-benzothiadiazole (BTD) unit is a prominent building block commonly used in various research areas such as optoelectronics and bioimaging. Despite its great versatility, the development of strategies to elaborate BTD has been largely neglected, including exploring its reactivity and understanding how regioselective functionalization can be used to tune the fluorescence emission. Previous focus has primarily been on C4- or C4,C7-substitutions. Here, a series of unsymmetrical mono - and disubstituted BTDs was synthesized and characterized for their photophysical properties. The reaction scope includes all six possible substituent patterns on the BTD benzoid ring (C4-, C5-, C4,C5-, C4,C6-, C4,C7- and C5,C6-substitution), which comprise arrangements that previously been synthetically challenging to access. By introducing a methoxy and/or a phenyl group we demonstrate that the emissive behavior of BTD derivatives strongly depends on the position of the substituent (s). We show that regioselective substitution on BTD can engender long-lived fluorescence and circumvent strong fluorescence quenching in polar protic solvents, which is a limitation of many previously described BTD derivatives.
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Affiliation(s)
| | - Christine Dyrager
- Department of Chemistry-BMC, Uppsala University, Box 576, 751 23, Uppsala, Sweden
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4
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Mońka M, Gogoc S, Kozakiewicz K, Ievtukhov V, Grzywacz D, Ciupak O, Kubicki A, Bojarski P, Data P, Serdiuk IE. Application of the Heavy-Atom Effect for (Sub)microsecond Thermally Activated Delayed Fluorescence and an All-Organic Light-Emitting Device with Low-Efficiency Roll-off. ACS APPLIED MATERIALS & INTERFACES 2024; 16:15107-15120. [PMID: 38497718 PMCID: PMC10982931 DOI: 10.1021/acsami.3c19627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Revised: 02/29/2024] [Accepted: 03/01/2024] [Indexed: 03/19/2024]
Abstract
The feature of abundant and environmentally friendly heavy atoms (HAs) like bromine to accelerate spin-forbidden transitions in organic molecules has been known for years. In combination with the easiness of incorporation, bromine derivatives of organic emitters showing thermally activated delayed fluorescence (TADF) emerge as a cheap and efficient solution for the slow reverse intersystem crossing (rISC) problem in such emitters and strong efficiency roll-off of all-organic light-emitting diodes (OLEDs). Here, we present a comprehensive photophysical study of a tri-PXZ-TRZ emitter reported previously and its hexabromo derivative showing a remarkable enhancement of rISC of up to 9 times and a short lifetime of delayed fluorescence of 2 μs. Analysis of the key molecular vibrations and TADF mechanism indicates almost compete blockage of the spin-flip transition between the charge-transfer states of different multiplicity 3CT → 1CT. In such a case, rISC as well as its enhancement by the HA is realized via the 3LE → 1CT transition, where 3LE is the triplet state localized on the same brominated phenoxazine donor involved in the formation of the 1CT state. Interestingly, the spin-orbit coupling (SOC) with two other 3LE states is negligible because they are localized on different donors and not involved in 1CT. We consider this as an example of an additional "localization" criterion that completes the well-known El Sayed rule on the different nature of states for nonzero SOC. The applicative potential of such a hexabromo emitter is tested in a "hyperfluorescent" system containing a red fluorescent dopant (tetraphenyldibenzoperiflanthene, DBP) as an acceptor of Förster resonance energy transfer, affording a narrow-band red-emitting system, with most of the emission in the submicrosecond domain. In fact, the fabricated red OLED devices show remarkable improvement of efficiency roll-off from 2-4 times depending on the luminance, mostly because of the increase of the rISC constant rate and the decrease of the overall delayed fluorescence lifetime thanks to the HA effect.
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Affiliation(s)
- Michał Mońka
- Faculty
of Mathematics, Physics and Informatics, University of Gdańsk, Wita Stwosza 57, 80-308 Gdańsk, Poland
| | - Szymon Gogoc
- Faculty
of Materials Science and Ceramics, AGH University
of Krakow, Mickiewicza 30, 30-059 Krakow, Poland
| | - Karol Kozakiewicz
- Faculty
of Mathematics, Physics and Informatics, University of Gdańsk, Wita Stwosza 57, 80-308 Gdańsk, Poland
- Faculty
of Chemistry, University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Vladyslav Ievtukhov
- Faculty
of Mathematics, Physics and Informatics, University of Gdańsk, Wita Stwosza 57, 80-308 Gdańsk, Poland
- Faculty
of Chemistry, University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Daria Grzywacz
- Faculty
of Mathematics, Physics and Informatics, University of Gdańsk, Wita Stwosza 57, 80-308 Gdańsk, Poland
- Faculty
of Chemistry, University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Olga Ciupak
- Department
of Organic Chemistry, Gdańsk University
of Technology, Gabriela Narutowicza 11/12, 80-233 Gdańsk, Poland
| | - Aleksander Kubicki
- Faculty
of Mathematics, Physics and Informatics, University of Gdańsk, Wita Stwosza 57, 80-308 Gdańsk, Poland
| | - Piotr Bojarski
- Faculty
of Mathematics, Physics and Informatics, University of Gdańsk, Wita Stwosza 57, 80-308 Gdańsk, Poland
| | - Przemysław Data
- Faculty
of Chemistry, Department of Molecular Physics, Lodz University of Technology, Zeromskiego 116, 90-543 Lodz, Poland
| | - Illia E. Serdiuk
- Faculty
of Mathematics, Physics and Informatics, University of Gdańsk, Wita Stwosza 57, 80-308 Gdańsk, Poland
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5
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Zhao X, Liu H, Mu Q, Fan J, Xu Y, Cai L. Modulating excited state properties of thermally activated delayed fluorescence molecules by hybrid long-range and short-range charge transfer strategy. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 308:123684. [PMID: 38039645 DOI: 10.1016/j.saa.2023.123684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 11/08/2023] [Accepted: 11/21/2023] [Indexed: 12/03/2023]
Abstract
Balancing the rapid radiative decay process and the fast reverse intersystem crossing (RISC) process of thermally activated delayed fluorescence (TADF) molecule remains a great challenge and efficient molecular design strategies are highly desired. Herein, from a theoretical perspective, excited state properties of three reported TADF molecules (1TICz, 1BOICz and 2BOICz) are investigated based on density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations coupled with the thermal vibration correlation function (TVCF) method. Results indicate that, by introducing the multi-resonance (MR) acceptor, 1BOICz possesses hybrid long-range and short-range charge transfer features, balanced small energy gap (ΔEST) and large oscillator strength (f) is obtained. Furthermore, by incorporating double equivalent MR acceptors in 2BOICz, largely enhanced f with slightly changed ΔEST is achieved, inner mechanism for remarkable photophysical property is illustrated. Keep this strategy, seven new TADF molecules (2pDBA-bICz-1, 2pDBA-bICz-2, 2OSBA-bICz, 2DQAO-bICz, 2QAO-bICz, 2SQAO-bICz and 2OQAO-bICz) are theoretically designed, detailed physical parameters are analyzed and excited state energy consumption process is studied. Strong electrophilicity on acceptor is determined and the strength of nucleophilic sites on the bridge-phenyl of 2DQAO-bICz, 2QAO-bICz, 2SQAO-bICz and 2OQAO-bICz is increased, this promotes the short-range charge transfer property. In addition, the excitation processes for all studied molecules are dominated by long-range charge transfer from donor to acceptors, and supplemented by the short-range charge transfer on the bridge-phenyl with MR effect. Compromise energy gap and oscillator strength as well as large spin orbit coupling (SOC) constant are obtained for designed molecules. Thus, by regulating the long-range and short-range charge transfer ratios, excited state properties are successfully modulated and new efficient TADF molecules are proposed. Our research aims to provide deeper insight into long-range and short-range charge transfer features in balancing small ΔEST and large f, which could facilitate the development of novel efficient TADF molecules.
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Affiliation(s)
- Xin Zhao
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Huanling Liu
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Qingfang Mu
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Jianzhong Fan
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China.
| | - Yuanyuan Xu
- School of Science, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
| | - Lei Cai
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China.
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6
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Wang L, Ge Z, Xu L, Song Y. An effective method in modulating thermally activated delayed fluorescence (TADF) emitters from green to blue emission: the role of the phenyl ring. Phys Chem Chem Phys 2024; 26:5597-5606. [PMID: 38285054 DOI: 10.1039/d3cp05632e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2024]
Abstract
Developing efficient blue emitters with high performance and low cost is crucial for the further development of organic light-emitting diodes (OLEDs). Based on the two experimentally reported green thermally activated delayed fluorescence (TADF) emitters, which are thioxanthone derivatives consisting of carbazole as an electron donor and 9H-thioxanthen-9-one-S,S-dioxide (SOXO) as an electron acceptor with donor-acceptor (D-A) or donor-acceptor-donor (D-A-D) structures, two new blue TADF emitters are designed by simply inserting a phenyl ring between D and A units. The TADF processes of the four thioxanthone derivatives are studied systematically through first-principles calculations. The role of the introduced phenyl ring in the excited state properties of the designed molecules is explored by analyzing the changes in molecular geometries, frontier molecular orbital distributions, the lowest singlet-triplet energy splitting (ΔEST), the spin orbit coupling (SOC) constants, the radiative decay rates (kr) and the nonradiative decay rates (knr), as well as the intersystem crossing rates (kISC) and reverse intersystem crossing rates (kRISC). The results show that when incorporating phenyl units into the D-A and D-A-D structures, both high kr and enhanced kRISC are achieved in Cz-Ph-SOXO and DCz-DPh-SOXO, demonstrating that incorporating the phenyl unit in D-A and D-A-D structures is an efficient way for developing new SOXO-based TADF molecules. It is worth noting that the kRISC values for Cz-Ph-SOXO and DCz-DPh-SOXO are significantly increased with respect to those of the experimental molecules. The present results would provide helpful guidelines for developing new SOXO-based TADF molecules experimentally.
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Affiliation(s)
- Lijuan Wang
- School of Materials Science and Engineering, Harbin Institute of Technology at Weihai, 2 West Wenhua Road, Weihai, 264209, China.
| | - Zhongqi Ge
- School of Materials Science and Engineering, Harbin Institute of Technology at Weihai, 2 West Wenhua Road, Weihai, 264209, China.
| | - Lin Xu
- School of Materials Science and Engineering, Harbin Institute of Technology at Weihai, 2 West Wenhua Road, Weihai, 264209, China.
| | - Yan Song
- School of Materials Science and Engineering, Harbin Institute of Technology at Weihai, 2 West Wenhua Road, Weihai, 264209, China.
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7
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Skhirtladze L, Keruckiene R, Bezvikonnyi O, Mahmoudi M, Volyniuk D, Leitonas K, Ghasemi M, Simokaitiene J, Nasir FHA, Ariffin A, Grazulevicius JV. Switching thermally activated delayed fluorescence to room temperature phosphorescence for oxygen sensing: Effect of donor substituents of trifluoromethylphenyl. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 306:123531. [PMID: 37890326 DOI: 10.1016/j.saa.2023.123531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 09/23/2023] [Accepted: 10/11/2023] [Indexed: 10/29/2023]
Abstract
Two compounds consisting of electron-accepting trifluoromethylphenyl moiety and electron-donating phenoxazine and phenothiazine moieties were designed and synthesized via Buchwald-Hartwig coupling reaction. Thermal, photophysical, and electrochemical properties of the compounds are discussed. Only compound with phenothiazine form molecular glass, with glass transition temperatures of 90 °C. The geometry and electronic characteristics of the compounds were substantiated within density functional theory (DFT). 10,10'-(2-(Trifluoromethyl)-1,4-phenylene)bis(10H-phenoxazine) shows efficient thermally activated delayed fluorescence with high spin-orbit coupling values. 10,10'-(2-(Trifluoromethyl)-1,4-phenylene)bis(10H-phenothiazine) as efficient room-temperature phosphor shows high oxygen sensitivity.
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Affiliation(s)
- Levani Skhirtladze
- Department of Polymer Chemistry and Technology, Faculty of Chemical Technology, Kaunas University of Technology, K. Baršausko st. 59, LT-51423 Kaunas, Lithuania.
| | - Rasa Keruckiene
- Department of Polymer Chemistry and Technology, Faculty of Chemical Technology, Kaunas University of Technology, K. Baršausko st. 59, LT-51423 Kaunas, Lithuania
| | - Oleksandr Bezvikonnyi
- Department of Polymer Chemistry and Technology, Faculty of Chemical Technology, Kaunas University of Technology, K. Baršausko st. 59, LT-51423 Kaunas, Lithuania; Department of Physics, Faculty of Mathematics and Natural Science, Kaunas University of Technology, Studentu˛ st. 50, LT-51369 Kaunas, Lithuania
| | - Malek Mahmoudi
- Department of Polymer Chemistry and Technology, Faculty of Chemical Technology, Kaunas University of Technology, K. Baršausko st. 59, LT-51423 Kaunas, Lithuania
| | - Dmytro Volyniuk
- Department of Polymer Chemistry and Technology, Faculty of Chemical Technology, Kaunas University of Technology, K. Baršausko st. 59, LT-51423 Kaunas, Lithuania
| | - Karolis Leitonas
- Department of Polymer Chemistry and Technology, Faculty of Chemical Technology, Kaunas University of Technology, K. Baršausko st. 59, LT-51423 Kaunas, Lithuania
| | - Melika Ghasemi
- Department of Polymer Chemistry and Technology, Faculty of Chemical Technology, Kaunas University of Technology, K. Baršausko st. 59, LT-51423 Kaunas, Lithuania
| | - Jurate Simokaitiene
- Department of Polymer Chemistry and Technology, Faculty of Chemical Technology, Kaunas University of Technology, K. Baršausko st. 59, LT-51423 Kaunas, Lithuania
| | - Farah Hannan Abd Nasir
- Low Dimensional Materials Research Centre (LDMRC), Department of Physics, Faculty of Science, University Malaya, 50603 Kuala Lumpur, Malaysia
| | - Azhar Ariffin
- Department of Chemistry, Faculty of Science, University Malaya, 50603 Kuala Lumpur, Malaysia
| | - Juozas V Grazulevicius
- Department of Polymer Chemistry and Technology, Faculty of Chemical Technology, Kaunas University of Technology, K. Baršausko st. 59, LT-51423 Kaunas, Lithuania
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8
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Guo T, Lin Y, Pan D, Zhang X, Zhu W, Cai XM, Huang G, Wang H, Xu D, Kühn FE, Zhang B, Zhang T. Towards bioresource-based aggregation-induced emission luminogens from lignin β-O-4 motifs as renewable resources. Nat Commun 2023; 14:6076. [PMID: 37770462 PMCID: PMC10539282 DOI: 10.1038/s41467-023-41681-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 09/14/2023] [Indexed: 09/30/2023] Open
Abstract
One-pot synthesis of heterocyclic aromatics with good optical properties from phenolic β-O-4 lignin segments is of high importance to meet high value added biorefinery demands. However, executing this process remains a huge challenge due to the incompatible reaction conditions of the depolymerization of lignin β-O-4 segments containing γ-OH functionalities and bioresource-based aggregation-induced emission luminogens (BioAIEgens) formation with the desired properties. In this work, benzannulation reactions starting from lignin β-O-4 moieties with 3-alkenylated indoles catalyzed by vanadium-based complexes have been successfully developed, affording a wide range of functionalized carbazoles with up to 92% yield. Experiments and density functional theory calculations suggest that the reaction pathway involves the selective cleavage of double C-O bonds/Diels-Alder cycloaddition/dehydrogenative aromatization. Photophysical investigations show that these carbazole products represent a class of BioAIEgens with twisted intramolecular charge transfer. Distinctions of emission behavior were revealed based on unique acceptor-donor-acceptor-type molecular conformations as well as molecular packings. This work features lignin β-O-4 motifs with γ-OH functionalities as renewable substrates, without the need to apply external oxidant/reductant systems. Here, we show a concise and sustainable route to functional carbazoles with AIE properties, building a bridge between lignin and BioAIE materials.
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Affiliation(s)
- Tenglong Guo
- CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| | - Yuting Lin
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
| | - Deng Pan
- Department of Chemistry, School of Science and Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Tianjin University, Tianjin, 300072, China
| | - Xuedan Zhang
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
| | - Wenqing Zhu
- CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| | - Xu-Min Cai
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China.
| | - Genping Huang
- Department of Chemistry, School of Science and Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Tianjin University, Tianjin, 300072, China.
| | - Hua Wang
- CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| | - Dezhu Xu
- CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| | - Fritz E Kühn
- Molecular Catalysis, Catalysis Research Center and Department of Chemistry, Technical University of Munich, Lichtenbergstr. 4, D-85748, Garching bei München, Germany
| | - Bo Zhang
- CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
| | - Tao Zhang
- CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
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9
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Liang Z, Wei M, Zhang S, Huang W, Shi N, Lv A, Ma H, He Z. Activating Molecular Room-Temperature Phosphorescence by Manipulating Excited-State Energy Levels in Poly(vinyl alcohol) Matrix. ACS APPLIED MATERIALS & INTERFACES 2023. [PMID: 37449496 DOI: 10.1021/acsami.3c06621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/18/2023]
Abstract
Poly(vinyl alcohol) (PVA) has been found as a wonderful matrix for chromophores to boost their room-temperature phosphorescence (RTP) character by forming abundant hydrogen bonding. Despite the well-utilized protective effect, the constructive role in accelerating the intersystem crossing is less investigated. Here, we focus on its role in manipulating the excited-state energy level to facilitate multiple intersystem crossing channels. Six benzoyl carbazole derivatives do not emit RTP in their solutions, powders, or crystals but exhibit significantly persistent RTP signals when embedded into the PVA matrix. Charge-transfer excited states were trapped by cofacial stacking in crystal, which blocks the intersystem crossing channels. In the PVA matrix, the allowed broad distribution of charge-transfer states covers the locally excited states, offering multiple intersystem crossing pathways via spin-vibronic orbit coupling. Consequently, efficient and persistent heavy-atom-free phosphors have been developed with the highest quantum yields of 7.7% and the longest lifetime of 2.3 s.
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Affiliation(s)
- Zhiwei Liang
- School of Science, Harbin Institute of Technology, Shenzhen, Guangdong 518055, China
| | - Mengqing Wei
- School of Science, Harbin Institute of Technology, Shenzhen, Guangdong 518055, China
| | - Shuai Zhang
- School of Science, Harbin Institute of Technology, Shenzhen, Guangdong 518055, China
| | - Wenbin Huang
- School of Science, Harbin Institute of Technology, Shenzhen, Guangdong 518055, China
| | - Ning Shi
- School of Science, Harbin Institute of Technology, Shenzhen, Guangdong 518055, China
| | - Anqi Lv
- Key Laboratory of Flexible Electronics & Institute of Advanced Materials Jiangsu National Synergistic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing, Jiangsu 211800, China
| | - Huili Ma
- Key Laboratory of Flexible Electronics & Institute of Advanced Materials Jiangsu National Synergistic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing, Jiangsu 211800, China
| | - Zikai He
- School of Science, Harbin Institute of Technology, Shenzhen, Guangdong 518055, China
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10
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Wright IA, Etherington MK, Batsanov AS, Monkman AP, Bryce MR. Oxidation State Tuning of Room Temperature Phosphorescence and Delayed Fluorescence in Phenothiazine and Phenothiazine-5,5-dioxide Dimers. Chemistry 2023; 29:e202300428. [PMID: 36916635 PMCID: PMC10946842 DOI: 10.1002/chem.202300428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 03/10/2023] [Accepted: 03/13/2023] [Indexed: 03/16/2023]
Abstract
Heterocyclic dimers consisting of combinations of butterfly-shaped phenothiazine (PTZ) and its chemically oxidized form phenothiazine-5,5-dioxide (PTZ(SO2 )) have been synthesized. A twist is imposed across the dimers by ortho-substituents including methyl ethers, sulfides and sulfones. X-ray crystallography, cyclic voltammetry and optical spectroscopy, underpinned by computational studies, have been employed to study the interplay between the oxidation state, conformational restriction, and emission mechanisms including thermally activated delayed fluorescence (TADF) and room temperature phosphorescence (RTP). While the PTZ(SO2 ) dimers are simple fluorophores, the presence of PTZ induces triplet-mediated emission with a mixed PTZ-PTZ(SO2 ) dimer displaying concentration dependent hallmarks of both TADF and RTP.
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Affiliation(s)
- Iain A. Wright
- Department of ChemistryDurham UniversitySouth RoadDurhamDH1 3LEUK
- School of ChemistryUniversity of EdinburghDavid Brewster RoadEdinburghEH9 3FJUK
| | - Marc K. Etherington
- Department of PhysicsDurham UniversitySouth RoadDurhamDH1 3LEUK
- Department of Mathematics, Physics and Electrical EngineeringNorthumbria UniversityEllison PlaceNewcastle upon TyneNE1 8STUK
| | | | | | - Martin R. Bryce
- Department of ChemistryDurham UniversitySouth RoadDurhamDH1 3LEUK
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11
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Nakae T, Hattori M, Yamanoi Y. 15N CP/MAS NMR as a Tool for the Mechanistic Study of Mechanical Stimuli-Responsive Materials: Evidence for the Conformational Change of an Emissive Dimethylacridane Derivative. ACS OMEGA 2023; 8:12922-12927. [PMID: 37065051 PMCID: PMC10099412 DOI: 10.1021/acsomega.3c00099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 03/17/2023] [Indexed: 06/19/2023]
Abstract
Mechanochromic luminescent molecules are currently attracting considerable attention because of their promising technological applications, but understanding their mechanism of action is challenging and is thus hindering our deeper understanding of these materials. The conformational change of 9,9'-dimethyl-9,10-dihydroacridane derivative 1 was examined using solid-state 15N nuclear magnetic resonance (NMR) spectroscopic techniques without using a specifically 15N-labeled compound. A difference between the two conformers was clearly observed in the measurements and was assigned to the ⟨pl⟩ and ⟨bf⟩ spatial structures. The results were supported by quantum chemical calculations on 15N NMR chemical shifts of each isomer. The technique presented here can clearly identify the structural changes caused by crushing a powder sample. Such structural changes are difficult to determine using X-ray diffraction (XRD) measurements.
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Affiliation(s)
- Toyotaka Nakae
- Department
of Applied Chemistry, Tokyo Metropolitan
University, 1-1 Minami-Osawa, Hachioji, Tokyo 192-0397, Japan
| | - Mineyuki Hattori
- National
Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Yoshinori Yamanoi
- Department
of Chemistry, School of Science, The University
of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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12
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Wu H, Shi YZ, Wang K, Yu J, Zhang XH. Conformational isomeric thermally activated delayed fluorescence (TADF) emitters: mechanism, applications, and perspectives. Phys Chem Chem Phys 2023; 25:2729-2741. [PMID: 36633179 DOI: 10.1039/d2cp05119b] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Thermally activated delayed fluorescence (TADF) materials have received enormous attention and the mechanism behind them has been investigated in depth. It has been found that some donor-acceptor (D-A) type TADF emitters could obviously exhibit dual stable conformations in the ground states and their distributions significantly affect the physical properties and device performances. Therefore, professional analysis and a summary of the relationship between molecular structures and performances are very important. In this review, we first summarize the mechanism and properties of TADF emitters with conformational isomerism. We also classify their recent progress according to their different applications, and provide an outlook on their perspectives.
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Affiliation(s)
- Hao Wu
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, P. R. China.
| | - Yi-Zhong Shi
- School of Materials Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, P. R. China.
| | - Kai Wang
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, P. R. China. .,Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, 215123, Jiangsu, P. R. China
| | - Jia Yu
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, P. R. China. .,Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou, 215123, Jiangsu, P. R. China
| | - Xiao-Hong Zhang
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, P. R. China. .,Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou, 215123, Jiangsu, P. R. China
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13
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Gao M, Tian Y, Li X, Gong Y, Fang M, Yang J, Li Z. The Effect of Molecular Conformations and Simulated "Self-Doping" in Phenothiazine Derivatives on Room-Temperature Phosphorescence. Angew Chem Int Ed Engl 2023; 62:e202214908. [PMID: 36449343 DOI: 10.1002/anie.202214908] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 11/29/2022] [Accepted: 11/30/2022] [Indexed: 12/03/2022]
Abstract
The research of purely organic room-temperature phosphorescence (RTP) materials has drawn great attention for their wide potential applications. Besides single-component and host-guest doping systems, the self-doping with same molecule but different conformations in one state is also a possible way to construct RTP materials, regardless of its rare investigation. In this work, twenty-four phenothiazine derivatives with two distinct molecular conformations were designed and their RTP behaviors in different states were systematically studied, with the aim to deeply understand the self-doping effect on the corresponding RTP property. While the phenothiazine derivatives with quasi-axial (ax) conformation presented better RTP performance in aggregated state, the quasi-equatorial (eq) ones were better in isolated state. Accordingly, the much promoted RTP performance was achieved in the stimulated self-doping state with ax-conformer as host and eq-one as guest, demonstrating the significant influence of self-doping on RTP effect.
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Affiliation(s)
- Mingxue Gao
- Institute of Molecular Aggregation Science, Tianjin University, Tianjin, 300072, China
| | - Yu Tian
- Institute of Molecular Aggregation Science, Tianjin University, Tianjin, 300072, China
| | - Xiaoning Li
- Institute of Molecular Aggregation Science, Tianjin University, Tianjin, 300072, China
| | - Yanxiang Gong
- Institute of Molecular Aggregation Science, Tianjin University, Tianjin, 300072, China
| | - Manman Fang
- Institute of Molecular Aggregation Science, Tianjin University, Tianjin, 300072, China
| | - Jie Yang
- Institute of Molecular Aggregation Science, Tianjin University, Tianjin, 300072, China
| | - Zhen Li
- Institute of Molecular Aggregation Science, Tianjin University, Tianjin, 300072, China.,Department of Chemistry, Wuhan University, Wuhan, 430072, China.,Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University, Binhai New City, Fuzhou, 350207, China.,Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China
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14
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Shen S, Baryshnikov GV, Xie Q, Wu B, Lv M, Sun H, Li Z, Ågren H, Chen J, Zhu L. Making multi-twisted luminophores produce persistent room-temperature phosphorescence. Chem Sci 2023; 14:970-978. [PMID: 36755727 PMCID: PMC9890967 DOI: 10.1039/d2sc05741g] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 12/16/2022] [Indexed: 12/23/2022] Open
Abstract
Multi-twisted molecules, especially those with more than four branched rotation axes, have served as superior prototypes in diverse fields like molecular machines, optical materials, sensors, and so forth. However, due to excessive non-radiative relaxation of these molecules, it remains challenging to address their persistent room-temperature phosphorescence (pRTP), which limits their further development. Herein, we develop a host-guest energy-transfer relay strategy to improve the phosphorescence lifetime of multi-twisted luminophores by over thousand-fold to realize pRTP, which can be witnessed by the naked eye after removing the excitation light source. Moreover, we employ photoexcitation-induced molecular rearrangement to further prolong the phosphorescence lifetime, which, to the best of our knowledge, is the first example of photoactivation in ordered host-guest systems. Our systems show superior humidity and oxygen resistance, enabling long-term (at least over 9-12 months) stability of the pRTP properties. By achieving pRTP of multi-twisted luminophores, this work can advance the understanding of molecular photophysical mechanisms and guide the study of more molecular systems that are difficult to achieve pRTP.
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Affiliation(s)
- Shen Shen
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University Shanghai 200438 China
| | - Glib V. Baryshnikov
- Laboratory of Organic Electronics, Department of Science and Technology, Linköping UniversityNorrköping 60174Sweden
| | - Qishan Xie
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University Shanghai 200438 China
| | - Bin Wu
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University Shanghai 200438 China
| | - Meng Lv
- State Key Laboratory of Precision Spectroscopy, East China Normal UniversityShanghai200241P. R. China
| | - Hao Sun
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University Shanghai 200438 China
| | - Zhongyu Li
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University Shanghai 200438 China
| | - Hans Ågren
- Department of Physics and Astronomy, Uppsala UniversityBox 516UppsalaSE-751 20Sweden
| | - Jinquan Chen
- State Key Laboratory of Precision Spectroscopy, East China Normal UniversityShanghai200241P. R. China
| | - Liangliang Zhu
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University Shanghai 200438 China
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15
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Zou H, Liu H, Mu Q, Zhang K, Song Y, Lin L, Xu Y, Wang CK, Fan J. Theoretical perspective for substitution effect on luminescent properties of through space charge transfer-based thermally activated delayed fluorescence molecules. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2023; 285:121899. [PMID: 36179564 DOI: 10.1016/j.saa.2022.121899] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 09/03/2022] [Accepted: 09/13/2022] [Indexed: 06/16/2023]
Abstract
Recently, through space charge transfer (TSCT)-based thermally activated delayed fluorescence (TADF) molecules have shown advantages in achieving high efficiencies and tunable emissions. However, the relationships between basic molecular structures and luminescent properties are unclear. Theoretical investigations to reveal the substitution effects with different numbers and positions on excited-state properties are highly desired. Herein, by taking TSCT-based TADF molecules S-CNDF-S-tCz, S-CNDF-D-tCz and T-CNDF-T-tCz as skeletons, a series of promising TADF molecules are designed by adopting ortho, meta and para substitutions with different numbers and positions. Photophysical properties of total 16 molecules are theoretically studied by density functional theory (DFT) and time-dependent density functional theory (TD-DFT) methods in chloroform combined with polarizable continuum model. Results indicate that molecules with ortho-substitution possess small geometric changes and short Donor-Acceptor distances which are induced by the intramolecular van der Waals interactions. Decreased non-radiative consumption and increased TSCT ratio and therefore excellent performance for them can be expected. For molecules with large substitution numbers, twist structures facilitate them to realize small adiabatic energy gaps between the lowest singlet excited state (S1) and the lowest triplet excited state (T1), this designing strategy is consistent with the TADF dendrimers. Thus, the relationships between molecular structures and luminescent properties are revealed and promising TSCT-based TADF molecules with high efficiencies are theoretically proposed. Our investigations provide theoretical perspectives for inner mechanisms of substitution effect, which could further afford meaningful guidance to design new efficient TSCT-based TADF molecules.
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Affiliation(s)
- Haipei Zou
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Huanling Liu
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Qingfang Mu
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Kai Zhang
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Yuzhi Song
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Lili Lin
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Yuanyuan Xu
- Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
| | - Chuan-Kui Wang
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China.
| | - Jianzhong Fan
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China; Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates (South China University of Technology), Guangzhou 510640, China.
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16
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Chaudhuri D, Patterson CH. TDDFT versus GW/BSE Methods for Prediction of Light Absorption and Emission in a TADF Emitter. J Phys Chem A 2022; 126:9627-9643. [PMID: 36515973 PMCID: PMC9806837 DOI: 10.1021/acs.jpca.2c06403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Design concepts for organic light emitting diode (OLED) emitters, which exhibit thermally activated delayed fluorescence (TADF) and thereby achieve quantum yields exceeding 25%, depend on singlet-triplet splitting energies of order kT to allow reverse intersystem crossing at ambient temperatures. Simulation methods for these systems must be able to treat relatively large organic molecules, as well as predict their excited state energies, transition energies, singlet-triplet splittings, and absorption and emission cross sections with reasonable accuracy, in order to prove useful in the design process. Here we compare predictions of TDDFT with M06-2X and ωB97X-D exchange-correlation functionals and a GoWo@HF/BSE method for these quantities in the well-studied DPTZ-DBTO2 TADF emitter molecule. Geometry optimization is performed for ground state (GS) and lowest donor-acceptor charge transfer (CT) state for each functional. Optical absorption and emission cross sections and energies are calculated at these geometries. Relaxation energies are on the order of 0.5 eV, and the importance of obtaining excited state equilibrium geometries in predicting delayed fluorescence is demonstrated. There are clear trends in predictions of GoWo@HF/BSE, and TDDFT/ωB97X-D and M06-2X methods in which the former method favors local exciton (LE) states while the latter favors DA CT states and ωB97X-D makes intermediate predictions. GoWo@HF/BSE suffers from triplet instability for LE states but not CT states relevant for TADF. Shifts in HOMO and LUMO levels on adding a conductor-like polarizable continuum model dielectric background are used to estimate changes in excitation energies on going from the gas phase to a solvated molecule.
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17
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Xia Y, Li J, Chen X, Li A, Guo K, Chen F, Zhao B, Chen Z, Wang H. Molecular Engineering of Push-Pull Diphenylsulfone Derivatives towards Aggregation-Induced Narrowband Deep Blue Thermally Activated Delayed Fluorescence (TADF) Emitters. Chemistry 2022; 28:e202202434. [PMID: 36168993 DOI: 10.1002/chem.202202434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Indexed: 12/29/2022]
Abstract
Narrowband deep blue thermally activated delayed fluorescent (TADF) materials have attracted significant attention. Herein, four asymmetrical structured TADF emitters based on diphenylsulfone (DPS) acceptor and 9,9-dimethyl-9,10-dihydroacridine (DMAC) donor with progressive performances were developed. The tert-butyloxy auxiliary electron-donor was adopted to restrict the intramolecular rotations and provide efficient steric hindrance. Regioisomerization by altering the substitution position of DMAC on DPS unit further enhanced the intra- and inter-molecular interactions. The accompanying effects yielded increased energy level, minimized reorganization energy, and inhibited non-radiative transitions in the crystals of tBuO-SOmAD, which achieved narrowband deep-blue emission peaking at 424 nm (FWHM=64 nm, ΦF =33.6 %) through aggregation-induced, blue-shifted emission (AIBSE). In addition, deep-blue organic light emitting diodes (OLEDs) based on tBuO-SOmAD realized the electroluminescence (EL) spectrum peaking located at 435 nm and CIE coordination of (0.12, 0.09).
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Affiliation(s)
- Yan Xia
- Ministry of Education Key Laboratory of, Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, Taiyuan, 030024, P. R. China
| | - Jie Li
- Ministry of Education Key Laboratory of, Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, Taiyuan, 030024, P. R. China
| | - Xu Chen
- School of Engineering Medicine, Beihang University, Beijing, 100191, P. R. China
| | - Anran Li
- School of Engineering Medicine, Beihang University, Beijing, 100191, P. R. China
| | - Kunpeng Guo
- Ministry of Education Key Laboratory of, Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, Taiyuan, 030024, P. R. China
| | - Fei Chen
- Ningbo Institute of NPU, Northwestern Polytechnical University, Ningbo, 315000, P. R. China
| | - Bo Zhao
- Ministry of Education Key Laboratory of, Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, Taiyuan, 030024, P. R. China
| | - Zhikuan Chen
- Ningbo Institute of NPU, Northwestern Polytechnical University, Ningbo, 315000, P. R. China
| | - Hua Wang
- Ministry of Education Key Laboratory of, Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, Taiyuan, 030024, P. R. China.,College of Textile Engineering, Taiyuan University of Technology, Jin Zhong, 030600, P. R. China
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18
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Constructing high-efficiency orange-red thermally activated delayed fluorescence emitters by three-dimension molecular engineering. Nat Commun 2022; 13:7828. [PMID: 36535962 PMCID: PMC9763412 DOI: 10.1038/s41467-022-35591-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 12/12/2022] [Indexed: 12/24/2022] Open
Abstract
Preparing high-efficiency solution-processable orange-red thermally activated delayed fluorescence (TADF) emitters remains challenging. Herein, we design a series of emitters consisting of trinaphtho[3,3,3]propellane (TNP) core derivatized with different TADF units. Benefiting from the unique hexagonal stacking architecture of TNPs, TADF units are thus kept in the cavities between two TNPs, which decrease concentration quenching and annihilation of long-lived triplet excitons. According to the molecular engineering of TADF and host units, the excited states can further be regulated to effectively enhance spin-orbit coupling (SOC) processes. We observe a high-efficiency orange-red emission at 604 nm in one instance with high SOC value of 0.862 cm-1 and high photoluminescence quantum yield of 70.9%. Solution-processable organic light-emitting diodes exhibit a maximum external quantum efficiency of 24.74%. This study provides a universal strategy for designing high-performance TADF emitters through molecular packing and excited state regulation.
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19
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Cha Y, Li S, Feng Z, Zhu R, Fu H, Yu Z. Organic Phosphorescence Lasing Based on a Thermally Activated Delayed Fluorescence Emitter. J Phys Chem Lett 2022; 13:10424-10431. [PMID: 36326286 DOI: 10.1021/acs.jpclett.2c02688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Organic phosphorescence materials provide an opportunity to use triplets for lasing. However, population inversion based on phosphorescence is hard to establish, owing to low luminescent quantum efficiency and intensive optical loss. By comparison, thermally activated delayed fluorescence emitters exhibit excellent optical gain with the aid of the reverse intersystem crossing (RISC) process. In this work, we designed a multifunctional gain material, not only serving as a thermally activated delayed fluorescence (TADF) emitter with excellent optical gain but also working as a phosphorescence source with high utilization of triplets. The lone pair of electrons in oxygen substitutions promotes a fast spin-flip and high delayed fluorescence quantum yield (ΦDF = 55%), enabling TADF amplified spontaneous emissions (ASE) of CH2Cl2 solution. Single-crystalline nanowires of H-aggregates effectively lower triplet energy levels with high phosphorescence quantum yield (ΦP = 27%), demonstrating Fabry-Perot mode phosphorescence lasing at 630 nm.
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Affiliation(s)
- Yongyu Cha
- Department of Chemistry, School of Science, Tianjin University, Tianjin300354, People's Republic of China
| | - Shuai Li
- Department of Chemistry, School of Science, Tianjin University, Tianjin300354, People's Republic of China
| | - Zuofang Feng
- Department of Chemistry, School of Science, Tianjin University, Tianjin300354, People's Republic of China
| | - Rongjiao Zhu
- Department of Chemistry, School of Science, Tianjin University, Tianjin300354, People's Republic of China
| | - Hongbing Fu
- Department of Chemistry, School of Science, Tianjin University, Tianjin300354, People's Republic of China
- Department of Chemistry, Capital Normal University, Beijing100048, People's Republic of China
| | - Zhenyi Yu
- Department of Chemistry, School of Science, Tianjin University, Tianjin300354, People's Republic of China
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20
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Tu C, Huang W, Liang S, Wang K, Tian Q, Yan W. Combining machine learning and quantum chemical calculations for high-throughput virtual screening of thermally activated delayed fluorescence molecular materials: the impact of selection strategy and structural mutations. RSC Adv 2022; 12:30962-30975. [PMID: 36349007 PMCID: PMC9619240 DOI: 10.1039/d2ra05643g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 10/09/2022] [Indexed: 11/23/2022] Open
Abstract
In view of the theoretical importance and huge application potential of Thermally Activated Delayed Fluorescence (TADF) materials, it is of great significance to conduct High-Throughput Virtual Screening (HTVS) on compound libraries to find TADF candidate molecules. This research focuses on the computational design of pure organic TADF molecules. By combining machine learning and quantum chemical calculations, using cheminformatics tools, and introducing the concept of selection and mutation from evolutionary theory, we have designed a computational program for HTVS of TADF molecular materials, especially the impact of selection strategy and structural mutations on the results of HTVS was explored. An initial compound library (size = 103) constructed by enumeration of typical donors and acceptors was used to evolve by successively applying selection and 10 different structural mutations. And a group fingerprint similarity (ΔMSPR) index was proposed to account for the similarity between two compound libraries with comparable sizes. Based on the computed data, we have found that the mix of selection and mutations into the evolution map does have great impact on the HTVS results: (a) except the fast mutation Sub2, all the rest of the mutations can effectively concentrate 'good' molecules in a compound library, and hence give large material abundance (typically >0.8) for high mutation generations (n g ≥ 6). (b) The mean energy gap can exhibit a fast convergent trend toward very low values, hence the studied mutations (except Sub2) can cooperate very well with the studied DA substrates to generate optimal molecules, and the group fingerprint similarity can retain high enough values for large n g, which can be associated with the apparent convergence in molecular skeletons as n g increases. (c) The distribution of skeleton frequencies for a specific mutation is generally uneven with one dominant skeleton. The overall numbers of common and generic cores for all mutations are 11 and 7 as n g = 9. Hence, in a sense, the 'optimal' skeletons seem unique and useful in realizing low energy gaps. With these observations and the development of related HTVS software, we expect to provide insight and tools to the research community of HTVS of molecular (TADF) materials.
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Affiliation(s)
- Chunyun Tu
- School of Chemistry and Materials Engineering, Guiyang UniversityGuiyang550005P. R. China+86-180-9605-0905
| | - Weijiang Huang
- School of Chemistry and Materials Engineering, Guiyang UniversityGuiyang550005P. R. China+86-180-9605-0905
| | - Sheng Liang
- School of Mathematics and Information Science, Guiyang UniversityGuiyang550005P. R. China
| | - Kui Wang
- School of Chemistry and Materials Engineering, Guiyang UniversityGuiyang550005P. R. China+86-180-9605-0905
| | - Qin Tian
- School of Chemistry and Materials Engineering, Guiyang UniversityGuiyang550005P. R. China+86-180-9605-0905
| | - Wei Yan
- School of Chemistry and Materials Engineering, Guiyang UniversityGuiyang550005P. R. China+86-180-9605-0905
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21
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Mahmoudi M, Gudeika D, Kutsiy S, Simokaitiene J, Butkute R, Skhirtladze L, Woon KL, Volyniuk D, Grazulevicius JV. Ornamenting of Blue Thermally Activated Delayed Fluorescence Emitters by Anchor Groups for the Minimization of Solid-State Solvation and Conformation Disorder Corollaries in Non-Doped and Doped Organic Light-Emitting Diodes. ACS APPLIED MATERIALS & INTERFACES 2022; 14:40158-40172. [PMID: 36000983 PMCID: PMC9460442 DOI: 10.1021/acsami.2c12475] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 08/09/2022] [Indexed: 06/15/2023]
Abstract
Motivated to minimize the effects of solid-state solvation and conformation disorder on emission properties of donor-acceptor-type emitters, we developed five new asymmetric multiple donor-acceptor type derivatives of tert-butyl carbazole and trifluoromethyl benzene exploiting different electron-accepting anchoring groups. Using this design strategy, for a compound containing four di-tert-butyl carbazole units as donors as well as 5-methyl pyrimidine and trifluoromethyl acceptor moieties, small singlet-triplet splitting of ca. 0.03 eV, reverse intersystem crossing rate of 1 × 106 s-1, and high photoluminescence quantum yield of neat film of ca. 75% were achieved. This compound was also characterized by the high value of hole and electron mobilities of 8.9 × 10-4 and 5.8 × 10-4 cm2 V-1 s-1 at an electric field of 4.7 × 105 V/cm, showing relatively good hole/electron balance, respectively. Due to the lowest conformational disorder and solid-state solvation effects, this compound demonstrated very similar emission properties (emission colors) in non-doped and differently doped organic light-emitting diodes (OLEDs). The lowest conformational disorder was observed for the compound with the additional accepting moiety inducing steric hindrance, limiting donor-acceptor dihedral rotational freedom. It can be exploited in the multi-donor-acceptor approach, increasing the efficiency. Using an emitter exhibiting the minimized solid-state solvation and conformation disorder effects, the sky blue OLED with the emitting layer of this compound dispersed in host 1,3-bis(N-carbazolyl)benzene displayed an emission peak at 477 nm, high brightness over 39 000 cd/m2, and external quantum efficiency up to 15.9% along with a maximum current efficiency of 42.6 cd/A and a maximum power efficiency of 24.1 lm/W.
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Affiliation(s)
- Malek Mahmoudi
- Department
of Polymer Chemistry and Technology, Kaunas
University of Technology, Radvilenu pl.19, Kaunas LT-50254, Lithuania
| | - Dalius Gudeika
- Department
of Polymer Chemistry and Technology, Kaunas
University of Technology, Radvilenu pl.19, Kaunas LT-50254, Lithuania
| | - Stepan Kutsiy
- Department
of Electronic Devices, Lviv Polytechnic
National University, S. Bandera 12, Lviv 79013, Ukraine
| | - Jurate Simokaitiene
- Department
of Polymer Chemistry and Technology, Kaunas
University of Technology, Radvilenu pl.19, Kaunas LT-50254, Lithuania
| | - Rita Butkute
- Department
of Polymer Chemistry and Technology, Kaunas
University of Technology, Radvilenu pl.19, Kaunas LT-50254, Lithuania
| | - Levani Skhirtladze
- Department
of Polymer Chemistry and Technology, Kaunas
University of Technology, Radvilenu pl.19, Kaunas LT-50254, Lithuania
| | - Kai Lin Woon
- Low
Dimensional Material Research Centre, Department of Physics, University Malaya, Kuala Lumpur 50603, Malaysia
| | - Dmytro Volyniuk
- Department
of Polymer Chemistry and Technology, Kaunas
University of Technology, Radvilenu pl.19, Kaunas LT-50254, Lithuania
| | - Juozas Vidas Grazulevicius
- Department
of Polymer Chemistry and Technology, Kaunas
University of Technology, Radvilenu pl.19, Kaunas LT-50254, Lithuania
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22
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Li M, Xie W, Cai X, Peng X, Liu K, Gu Q, Zhou J, Qiu W, Chen Z, Gan Y, Su S. Molecular Engineering of Sulfur‐Bridged Polycyclic Emitters Towards Tunable TADF and RTP Electroluminescence. Angew Chem Int Ed Engl 2022; 61:e202209343. [DOI: 10.1002/anie.202209343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Indexed: 11/06/2022]
Affiliation(s)
- Mengke Li
- State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices South China University of Technology Wushan Road 381 Tianhe District, Guangzhou 510640, Guangdong Province P. R. China
| | - Wentao Xie
- State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices South China University of Technology Wushan Road 381 Tianhe District, Guangzhou 510640, Guangdong Province P. R. China
| | - Xinyi Cai
- State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices South China University of Technology Wushan Road 381 Tianhe District, Guangzhou 510640, Guangdong Province P. R. China
| | - Xiaomei Peng
- State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices South China University of Technology Wushan Road 381 Tianhe District, Guangzhou 510640, Guangdong Province P. R. China
| | - Kunkun Liu
- State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices South China University of Technology Wushan Road 381 Tianhe District, Guangzhou 510640, Guangdong Province P. R. China
| | - Qing Gu
- State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices South China University of Technology Wushan Road 381 Tianhe District, Guangzhou 510640, Guangdong Province P. R. China
| | - Jiadong Zhou
- State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices South China University of Technology Wushan Road 381 Tianhe District, Guangzhou 510640, Guangdong Province P. R. China
| | - Weidong Qiu
- State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices South China University of Technology Wushan Road 381 Tianhe District, Guangzhou 510640, Guangdong Province P. R. China
| | - Zijian Chen
- State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices South China University of Technology Wushan Road 381 Tianhe District, Guangzhou 510640, Guangdong Province P. R. China
| | - Yiyang Gan
- State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices South China University of Technology Wushan Road 381 Tianhe District, Guangzhou 510640, Guangdong Province P. R. China
| | - Shi‐Jian Su
- State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices South China University of Technology Wushan Road 381 Tianhe District, Guangzhou 510640, Guangdong Province P. R. China
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23
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Shen X, Li M, Zhou T, Huang J. Benzo[
b
]naphtho[1,2‐
d
]thiophene Sulfoxides: Biomimetic Synthesis, Photophysical Properties, and Applications. Angew Chem Int Ed Engl 2022; 61:e202203908. [DOI: 10.1002/anie.202203908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Indexed: 11/08/2022]
Affiliation(s)
- Xian‐Yan Shen
- School of Pharmacy Tongji Medical College Huazhong University of Science and Technology Wuhan 430030, Hubei Province China
| | - Man Li
- Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of Education School of Chemistry and Chemical Engineering Huazhong University of Science and Technology Wuhan 430030, Hubei Province China
| | - Tai‐Ping Zhou
- Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of Education School of Chemistry and Chemical Engineering Huazhong University of Science and Technology Wuhan 430030, Hubei Province China
| | - Ji‐Rong Huang
- School of Pharmacy Tongji Medical College Huazhong University of Science and Technology Wuhan 430030, Hubei Province China
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24
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Gu Q, Chotard F, Eng J, Reponen APM, Vitorica-Yrezabal IJ, Woodward AW, Penfold TJ, Credgington D, Bochmann M, Romanov AS. Excited-State Lifetime Modulation by Twisted and Tilted Molecular Design in Carbene-Metal-Amide Photoemitters. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2022; 34:7526-7542. [PMID: 36032551 PMCID: PMC9404540 DOI: 10.1021/acs.chemmater.2c01938] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 07/25/2022] [Indexed: 06/15/2023]
Abstract
Carbene-metal-amides (CMAs) are an emerging class of photoemitters based on a linear donor-linker-acceptor arrangement. They exhibit high flexibility about the carbene-metal and metal-amide bonds, leading to a conformational freedom which has a strong influence on their photophysical properties. Herein we report CMA complexes with (1) nearly coplanar, (2) twisted, (3) tilted, and (4) tilt-twisted orientations between donor and acceptor ligands and illustrate the influence of preferred ground-state conformations on both the luminescence quantum yields and excited-state lifetimes. The performance is found to be optimum for structures with partially twisted and/or tilted conformations, resulting in radiative rates exceeding 1 × 106 s-1. Although the metal atoms make only small contributions to HOMOs and LUMOs, they provide sufficient spin-orbit coupling between the low-lying excited states to reduce the excited-state lifetimes down to 500 ns. At the same time, high photoluminescence quantum yields are maintained for a strongly tilted emitter in a host matrix. Proof-of-concept organic light-emitting diodes (OLEDs) based on these new emitter designs were fabricated, with a maximum external quantum efficiency (EQE) of 19.1% with low device roll-off efficiency. Transient electroluminescence studies indicate that molecular design concepts for new CMA emitters can be successfully translated into the OLED device.
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Affiliation(s)
- Qinying Gu
- Department
of Physics, Cavendish Laboratory, Cambridge
University, Cambridge CB3 0HF, U.K.
| | - Florian Chotard
- School
of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, U.K.
| | - Julien Eng
- School
of Chemistry, Newcastle University, Bedson Building, Newcastle upon Tyne, NE1 7RU, U.K.
| | - Antti-Pekka M. Reponen
- Department
of Physics, Cavendish Laboratory, Cambridge
University, Cambridge CB3 0HF, U.K.
| | | | - Adam W. Woodward
- Department
of Chemistry, University of Manchester, Manchester, M13 9PL, U.K.
| | - Thomas J. Penfold
- School
of Chemistry, Newcastle University, Bedson Building, Newcastle upon Tyne, NE1 7RU, U.K.
| | - Dan Credgington
- Department
of Physics, Cavendish Laboratory, Cambridge
University, Cambridge CB3 0HF, U.K.
| | - Manfred Bochmann
- School
of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, U.K.
| | - Alexander S. Romanov
- School
of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, U.K.
- Department
of Chemistry, University of Manchester, Manchester, M13 9PL, U.K.
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25
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Wang T, De J, Wu S, Gupta AK, Zysman‐Colman E. Thermally Activated and Aggregation‐Regulated Excitonic Coupling Enable Emissive High‐Lying Triplet Excitons**. Angew Chem Int Ed Engl 2022; 61:e202206681. [PMID: 35684990 PMCID: PMC9545188 DOI: 10.1002/anie.202206681] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Indexed: 11/06/2022]
Abstract
Room‐temperature phosphorescence (RTP) originating from higher‐lying triplet excitons remains a rather rarely documented occurrence for purely organic molecular systems. Here, we report two naphthalene‐based RTP luminophores whose phosphorescence emission is enabled by radiative decay of high‐lying triplet excitons. In contrast, upon cooling the dominant phosphorescence originates from the lowest‐lying triplet excited state, which is manifested by a red‐shifted emission. Photophysical and theoretical studies reveal that the unusual RTP results from thermally activated excitonic coupling between different conformations of the compounds. Aggregation‐regulated excitonic coupling is observed when increasing the doping concentration of the emitters in poly(methylmethacrylate) (PMMA). Further, the RTP quantum efficiency improves more than 80‐fold in 1,3‐bis(N‐carbazolyl)benzene (mCP) compared to that in PMMA. This design principle offers important insight into triplet excited state dynamics and has been exploited in afterglow‐indicating temperature sensing.
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Affiliation(s)
- Tao Wang
- Organic Semiconductor Centre EaStCHEM School of Chemistry University of St Andrews St Andrews KY16 9ST UK
| | - Joydip De
- Organic Semiconductor Centre EaStCHEM School of Chemistry University of St Andrews St Andrews KY16 9ST UK
| | - Sen Wu
- Organic Semiconductor Centre EaStCHEM School of Chemistry University of St Andrews St Andrews KY16 9ST UK
| | - Abhishek Kumar Gupta
- Organic Semiconductor Centre EaStCHEM School of Chemistry University of St Andrews St Andrews KY16 9ST UK
| | - Eli Zysman‐Colman
- Organic Semiconductor Centre EaStCHEM School of Chemistry University of St Andrews St Andrews KY16 9ST UK
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26
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27
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Li M, Xie W, Cai X, Peng X, Liu K, Gu Q, Zhou J, Qiu W, Chen Z, Gan Y, Su SJ. Molecular Engineering of Sulfur‐Bridged Polycyclic Emitters Towards Tunable TADF and RTP Electroluminescence. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202209343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Mengke Li
- South China University of Technology State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices CHINA
| | - Wentao Xie
- South China University of Technology State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices CHINA
| | - Xinyi Cai
- South China University of Technology State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices CHINA
| | - Xiaomei Peng
- South China University of Technology State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices CHINA
| | - Kunkun Liu
- South China University of Technology State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices CHINA
| | - Qing Gu
- South China University of Technology State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices CHINA
| | - Jiadong Zhou
- South China University of Technology State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices CHINA
| | - Weidong Qiu
- South China University of Technology State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices CHINA
| | - Zijian Chen
- South China University of Technology State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices CHINA
| | - Yiyang Gan
- South China University of Technology State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices CHINA
| | - Shi-Jian Su
- South China University of Technology School of Materials Science and Engineering State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices 381 Wushan Road 510640 Guangzhou CHINA
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28
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Shen XY, Li M, Zhou TP, Huang JR. Benzo[b]naphtho[1,2‐d]thiophene Sulfoxides: Biomimetic Synthesis, Photophysical Properties, and Applications. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202203908] [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)
- Xian-Yan Shen
- Huazhong University of Science and Technology Tongji Medical College School of Pharmacy CHINA
| | - Man Li
- Huazhong University of Science and Technology School of Chemistry and Chemical Engineering CHINA
| | - Tai-Ping Zhou
- Huazhong University of Science and Technology School of Chemistry and Chemical Engineering CHINA
| | - Ji-Rong Huang
- Huazhong University of Science and Technology Tongji Medical College School of Pharmacy 13 Hangkong Road 430030 Wuhan CHINA
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29
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Wang T, De J, Wu S, Gupta AK, Zysman-Colman E. Thermally activated and aggregation‐regulated excitonic coupling enable emissive high‐lying triplet excitons. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202206681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Tao Wang
- University of St Andrews Chemistry UNITED KINGDOM
| | - Joydip De
- University of St Andrews Chemistry UNITED KINGDOM
| | - Sen Wu
- University of St Andrews Chemistry UNITED KINGDOM
| | | | - Eli Zysman-Colman
- University of St Andrews School of Chemistry Purdie BuildingNorth Haugh KY16 9ST St Andrews UNITED KINGDOM
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30
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Lv M, Han C, Li Z, Zhou P, Li W, Liu J. Impact of regiochemistry on thermal stability of trifuroxan based energetic materials: A theoretical perspective. COMPUT THEOR CHEM 2022. [DOI: 10.1016/j.comptc.2022.113686] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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31
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Lv M, Wang T, Zhou P, He Y, Li W, Liu J. Theoretical insights into the role of regiochemistry in thermal stability regulation of energetic materials. Chem Phys Lett 2022. [DOI: 10.1016/j.cplett.2022.139720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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32
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Tan HJ, Yang GX, Deng YL, Cao C, Tan JH, Zhu ZL, Chen WC, Xiong Y, Jian JX, Lee CS, Tong QX. Deep-Blue OLEDs with Rec.2020 Blue Gamut Compliance and EQE Over 22% Achieved by Conformation Engineering. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2200537. [PMID: 35236007 DOI: 10.1002/adma.202200537] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 02/28/2022] [Indexed: 06/14/2023]
Abstract
To achieve high-efficiency deep-blue electroluminescence satisfying Rec.2020 standard blue gamut, two thermally activated delayed fluorescent (TADF) emitters are developed: 5-(2,12-di-tert-butyl-5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracen-7-yl)-10,10-diphenyl-5,10-dihydrodibenzo[b,e][1,4]azasiline (TDBA-PAS) and 10-(2,12-di-tert-butyl-5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracen-7-yl)-9,9-diphenyl-9,10-dihydroacridine (TDBA-DPAC). Inheriting from their parented organoboron multi-resonance core, both emitters show very promising deep-blue emissions with relatively narrow full width at half-maximum (FWHM, ≈50 nm in solution), high photoluminescence quantum yield (up to 92.3%), and short emission lifetime (≤2.49 µs) with fast reverse intersystem crossing (>106 s-1 ) in doped films. More importantly, replacing the spiro-centered sp3 C atom (TDBA-DPAC) with the larger-radius sp3 Si atom (TDBA-PAS), enhanced conformational heterogeneities in bulky-group-shielded TADF molecules are observed in solution, doped film, and device. Consequently, OLEDs based on TDBA-PAS retain high maximum external quantum efficiencies ≈20% with suppressed efficiency roll-off and color index close to Rec.2020 blue gamut over a wide doping range of 10-50 wt%. This study highlights a new strategy to restrain spectral broadening and redshifting and efficiency roll-off in the design of deep-blue TADF emitters.
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Affiliation(s)
- Hong-Ji Tan
- 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
| | - Ying-Lan Deng
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P. R. China
| | - Chen Cao
- Center of Super-Diamond and Advanced Films (COSDAF) and Department of Chemistry, City University of Hong Kong, Hong Kong, SAR, China
| | - Ji-Hua Tan
- Center of Super-Diamond and Advanced Films (COSDAF) and Department of Chemistry, City University of Hong Kong, Hong Kong, SAR, China
| | - Ze-Lin Zhu
- Center of Super-Diamond and Advanced Films (COSDAF) and Department of Chemistry, City University of Hong Kong, Hong Kong, SAR, China
| | - Wen-Cheng Chen
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, 510006, China
| | - Yuan Xiong
- Center of Super-Diamond and Advanced Films (COSDAF) and Department of Chemistry, City University of Hong Kong, Hong Kong, SAR, China
| | - Jing-Xin Jian
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P. R. China
| | - Chun-Sing Lee
- Center of Super-Diamond and Advanced Films (COSDAF) and Department of Chemistry, City University of Hong Kong, Hong Kong, SAR, 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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33
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Maggiore A, Qu Y, Guillot R, Pander P, Vasylieva M, Data P, Dias FB, Audebert P, Clavier G, Miomandre F. Novel Easy to Synthesize Benzonitrile Compounds with Mixed Carbazole and Phenoxazine Substituents Exhibiting Dual Emission and TADF Properties. J Phys Chem B 2022; 126:2740-2753. [PMID: 35353524 DOI: 10.1021/acs.jpcb.2c00219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The photophysical and electrochemical properties of a new class of fluorinated benzonitrile compounds substituted with mixed phenoxazine and carbazole units have been investigated. When absorbing in a large range of the UV-vis spectrum due to both localized and charge-transfer absorptions, these compounds show dual broad emission in solution and intense emission in PMMA films, with photoluminescence quantum yields changing from a few percent in solution to 18% in a more rigid environment. The compounds also exhibit thermally activated delayed fluorescence demonstrated by the role of oxygen in the quenching of delayed fluorescence and by time-resolved luminescence studies, with an efficiency directly related to the number of phenoxazine substituents. Electrochemistry reveals dramatic changes in the reduction mechanisms according to the number of remaining fluorine atoms on the benzonitrile core. All these results demonstrate how it is possible to tune the photophysical and electrochemical properties of easily synthesizable derivatives by controlling the nature and relative number of the substituents on a simple aromatic platform.
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Affiliation(s)
- Antonio Maggiore
- Université Paris-Saclay, ENS Paris-Saclay, CNRS, PPSM, 91190 Gif-sur-Yvette, France
| | - Yangyang Qu
- Université Paris-Saclay, ENS Paris-Saclay, CNRS, PPSM, 91190 Gif-sur-Yvette, France
| | - Régis Guillot
- Université Paris-Saclay, CNRS, ICMMO, 91405 Orsay, France
| | - Piotr Pander
- Department of Physics, University of Durham, South Road, DH1 3LE Durham, U.K.,Centre for Organic and Nanohybrid Electronics, Silesian University of Technology, Konarskiego 22B, 44-100 Gliwice, Poland
| | - Marharyta Vasylieva
- Centre of Polymer and Carbon Materials of the Polish Academy of Sciences, ul. M. Curie-Skłodowskiej 34, 41-819 Zabrze, Poland
| | - Przemyslaw Data
- Department of Physics, University of Durham, South Road, DH1 3LE Durham, U.K.,Centre for Organic and Nanohybrid Electronics, Silesian University of Technology, Konarskiego 22B, 44-100 Gliwice, Poland
| | - Fernando B Dias
- Department of Physics, University of Durham, South Road, DH1 3LE Durham, U.K
| | - Pierre Audebert
- Université Paris-Saclay, ENS Paris-Saclay, CNRS, PPSM, 91190 Gif-sur-Yvette, France
| | - Gilles Clavier
- Université Paris-Saclay, ENS Paris-Saclay, CNRS, PPSM, 91190 Gif-sur-Yvette, France
| | - Fabien Miomandre
- Université Paris-Saclay, ENS Paris-Saclay, CNRS, PPSM, 91190 Gif-sur-Yvette, France
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34
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Roy B, Maisuls I, Zhang J, Niemeyer FC, Rizzo F, Wölper C, Daniliuc CG, Tang BZ, Strassert CA, Voskuhl J. Mapping the Regioisomeric Space and Visible Color Range of Purely Organic Dual Emitters with Ultralong Phosphorescence Components: From Violet to Red Towards Pure White Light. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202111805] [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)
- Bibhisan Roy
- Faculty of Chemistry (Organic Chemistry) and Center for NanoIntegration (CENIDE) University of Duisburg-Essen Universitätsstrasse 7 45117 Essen Germany
| | - Iván Maisuls
- Institut für Anorganische und Analytische Chemie CeNTech, CiMIC, SoN Westfälische Wilhelms-Universität Münster Heisenbergstraße 11 48149 Münster Germany
| | - Jianyu Zhang
- Department of Chemistry Hong Kong University of Science and Technology (HKUST) Clear water Bay Kowloon Hong Kong
| | - Felix C. Niemeyer
- Faculty of Chemistry (Organic Chemistry) and Center for NanoIntegration (CENIDE) University of Duisburg-Essen Universitätsstrasse 7 45117 Essen Germany
| | - Fabio Rizzo
- Organisch Chemisches Institut Westfälische Wilhelms-Universität Münster (F.R. and C.G.D.) and SoN (F.R.) Corrensstraße 36 48149 Münster Germany
- Institute of Chemical Science and Technologies “G. Natta” (SCITEC) National Research Council (CNR) Via G. Fantoli 16/15 20138 Milan Italy
| | - Christoph Wölper
- Institute for Inorganic Chemistry and Center for NanoIntegration (CENIDE) University of Duisburg-Essen Universitätsstrasse 5–7 45117 Essen Germany
| | - Constantin G. Daniliuc
- Organisch Chemisches Institut Westfälische Wilhelms-Universität Münster (F.R. and C.G.D.) and SoN (F.R.) Corrensstraße 36 48149 Münster Germany
| | - Ben Zhong Tang
- Department of Chemistry Hong Kong University of Science and Technology (HKUST) Clear water Bay Kowloon Hong Kong
| | - Cristian A. Strassert
- Institut für Anorganische und Analytische Chemie CeNTech, CiMIC, SoN Westfälische Wilhelms-Universität Münster Heisenbergstraße 11 48149 Münster Germany
| | - Jens Voskuhl
- Faculty of Chemistry (Organic Chemistry) and Center for NanoIntegration (CENIDE) University of Duisburg-Essen Universitätsstrasse 7 45117 Essen Germany
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35
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Duda E, Hall D, Bagnich S, Carpenter-Warren CL, Saxena R, Wong MY, Cordes DB, Slawin AMZ, Beljonne D, Olivier Y, Zysman-Colman E, Köhler A. Enhancing Thermally Activated Delayed Fluorescence by Fine-Tuning the Dendron Donor Strength. J Phys Chem B 2022; 126:552-562. [PMID: 34995068 DOI: 10.1021/acs.jpcb.1c05749] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Thermally activated delayed fluorescence (TADF) relies on a small energy gap between the emissive singlet and the nonemissive triplet state, obtained by reducing the wave function overlap between donor and acceptor moieties. Efficient emission, however, requires maintaining a good oscillator strength, which is itself based on sufficient overlap of the wave functions between donor and acceptor moieties. We demonstrate an approach to subtly fine-tune the required wave function overlap by employing donor dendrons of changing functionality. We use a carbazolyl-phthalonitrile based donor-acceptor core (2CzPN) as a reference emitter and progressively localize the hole density through substitution at the 3,6-positions of the carbazole donors (Cz) with further carbazole, (4-tert-butylphenyl)amine (tBuDPA), and phenoxazine (PXZ). Using detailed photoluminescence studies, complemented with density functional theory (DFT) calculations, we show that this approach permits a gradual decrease of the singlet-triplet gap, ΔEST, from 300 to around 10 meV in toluene, yet we also demonstrate why a small ΔEST alone is not enough. While sufficient oscillator strength is maintained with the Cz- and tBuDPA-based donor dendrons, this is not the case for the PXZ-based donor dendron, where the wave function overlap is reduced too strongly. Overall, we find the donor dendron extension approach allows successful fine-tuning of the emitter photoluminescence properties.
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Affiliation(s)
- Eimantas Duda
- Soft Matter Optoelectronics, BIMF & BPI, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
| | - David Hall
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, U.K., KY16 9ST.,Laboratory for Chemistry of Novel Materials, University of Mons, 7000, Mons, Belgium
| | - Sergey Bagnich
- Soft Matter Optoelectronics, BIMF & BPI, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
| | - Cameron L Carpenter-Warren
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, U.K., KY16 9ST
| | - Rishabh Saxena
- Soft Matter Optoelectronics, BIMF & BPI, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
| | - Michael Y Wong
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, U.K., KY16 9ST
| | - David B Cordes
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, U.K., KY16 9ST
| | - Alexandra M Z Slawin
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, U.K., KY16 9ST
| | - David Beljonne
- Laboratory for Chemistry of Novel Materials, University of Mons, 7000, Mons, Belgium
| | - Yoann Olivier
- Unité de Chimie Physique Théorique et Structurale & Laboratoire de Physique du Solide, Namur Institute of Structured Matter, Université de Namur, Rue de Bruxelles, 61, 5000 Namur, Belgium
| | - Eli Zysman-Colman
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, U.K., KY16 9ST
| | - Anna Köhler
- Soft Matter Optoelectronics, BIMF & BPI, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
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Shi YZ, Wu H, Wang K, Yu J, Ou XM, Zhang XH. Recent progress in thermally activated delayed fluorescence emitters for nondoped organic light-emitting diodes. Chem Sci 2022; 13:3625-3651. [PMID: 35432901 PMCID: PMC8966661 DOI: 10.1039/d1sc07180g] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Accepted: 02/21/2022] [Indexed: 11/25/2022] Open
Abstract
Nondoped organic light-emitting diodes (OLEDs) have drawn immense attention due to their merits of process simplicity, reduced fabrication cost, etc. To realize high-performance nondoped OLEDs, all electrogenerated excitons should be fully utilized. The thermally activated delayed fluorescence (TADF) mechanism can theoretically realize 100% internal quantum efficiency (IQE) through an effective upconversion process from nonradiative triplet excitons to radiative singlet ones. Nevertheless, exciton quenching, especially related to triplet excitons, is generally very serious in TADF-based nondoped OLEDs, significantly hindering the pace of development. Enormous efforts have been devoted to alleviating the annoying exciton quenching process, and a number of TADF materials for highly efficient nondoped devices have been reported. In this review, we mainly discuss the mechanism, exciton leaking channels, and reported molecular design strategies of TADF emitters for nondoped devices. We further classify their molecular structures depending on the functional A groups and offer an outlook on their future prospects. It is anticipated that this review can entice researchers to recognize the importance of TADF-based nondoped OLEDs and provide a possible guide for their future development. The mechanism, exciton leaking channels, and reported molecular design strategies of TADF emitters for high-performance nondoped OLEDs are summarized. Their molecular structures depending on the functional A groups are further classified.![]()
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Affiliation(s)
- Yi-Zhong Shi
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University 199 Ren'ai Road Suzhou Jiangsu 215123 PR China
| | - Hao Wu
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University 199 Ren'ai Road Suzhou Jiangsu 215123 PR China
| | - Kai Wang
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University 199 Ren'ai Road Suzhou Jiangsu 215123 PR China
| | - Jia Yu
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University 199 Ren'ai Road Suzhou Jiangsu 215123 PR China
| | - Xue-Mei Ou
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University 199 Ren'ai Road Suzhou Jiangsu 215123 PR China
| | - Xiao-Hong Zhang
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University 199 Ren'ai Road Suzhou Jiangsu 215123 PR China
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37
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Wang X, Wu Y, Wu CM, Li Y, Wang D, Wu Y, Ning S, Jiao B, Wu Z. Dibenzo[ f, h]furo[2,3- b]quinoxaline-based molecular scaffolds as deep blue fluorescence materials for organic light-emitting diodes. NEW J CHEM 2022. [DOI: 10.1039/d1nj04934h] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel molecular scaffold, dibenzo[f,h]furo[2,3-b]quinoxaline (3,6-bis(4-isopropylphenyls)-11-phenyldibenzo[f,h]furo[2,3-b]quinoxaline (dP-diBFQ) and furo[2′,3′:5,6]pyrazino[2,3-f][1,10]phenanthroline, were designed, for pure and deep blue emission. OLEDs based on dP-diBFQ shows pure blue emission with CIE coordinates of (0.154, 0.102) and an EQE of 2.28%.
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Affiliation(s)
- Xinye Wang
- School of Chemistry, Xi’an Jiaotong University, Xi’an 710049, P. R. China
| | - Yuan Wu
- School of Electronic Information and Artificial Intelligence, Shaanxi University of Science and Technology, Xi’an, Shaanxi, 710021, P. R. China
| | - Chuan Ming Wu
- School of Chemistry, Xi’an Jiaotong University, Xi’an 710049, P. R. China
| | - Yixiang Li
- School of Chemistry, Xi’an Jiaotong University, Xi’an 710049, P. R. China
| | - Dongdong Wang
- School of Chemistry, Xi’an Jiaotong University, Xi’an 710049, P. R. China
| | - Yong Wu
- School of Chemistry, Xi’an Jiaotong University, Xi’an 710049, P. R. China
| | - Shuya Ning
- School of Electronic Information and Artificial Intelligence, Shaanxi University of Science and Technology, Xi’an, Shaanxi, 710021, P. R. China
| | - Bo Jiao
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education & Shaanxi Key Lab of Information Photonic Technique, School of Electronic and Information Engineering, Xi’an Jiaotong University, Xi’an 710049, P. R. China
| | - Zhaoxin Wu
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education & Shaanxi Key Lab of Information Photonic Technique, School of Electronic and Information Engineering, Xi’an Jiaotong University, Xi’an 710049, P. R. China
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38
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Lv Z, Hou J, Yao J, Yuan Y, Qian Y, Zhu J, Zhao H, Xiong X, Jiao C. Investigation on fluorescein derivatives with thermally activated delayed fluorescence and their applications in imaging. RSC Adv 2022; 12:11477-11483. [PMID: 35425056 PMCID: PMC9007153 DOI: 10.1039/d2ra00593j] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 03/30/2022] [Indexed: 12/13/2022] Open
Abstract
Fluorescein derivatives with thermally activated delayed fluorescence (TADF) show much stronger competition ability and vaster prospects than traditional fluorescein dyes due to their prominent long lifetime. It will be of great significance to synthesize more fluorescein derivatives with TADF. In this work, compounds DCF-MPYA and FL with TADF properties were obtained by fine tuning the substituents' structure on the basis of fluorescein derivative DCF-MPYM. Their long-lived triplet excited states (21.78 μs, 32.0 μs) were proved by nanosecond time-resolved transient difference absorption spectra. The steady-state and time-resolved fluorescence spectra showed that DCF-MPYA and FL exhibited red fluorescence around 645 nm and 651 nm, respectively. The results of sensitivity to oxygen and heavy atoms further demonstrated that the time-resolved fluorescence spectra originate from the delayed fluorescence. The time correlated single-photon counting (TCSPC) data indicated that DCF-MPYA and FL showed long-lived lifetimes of 13.16 μs and 23.72 μs, respectively. The energy gap (ΔEST) between the singlet (S1) and triplet (T1) states of DCF-MPYA and FL was calculated to be 3.32 meV and 9.98 meV from the decay rate of DF as a function of temperature. The small energy gap is conducive to the occurrence of efficient TADF at room temperature. Meanwhile, Gaussian calculation was employed to observe the electron density of DCF-MPYA and FL in the ground and excited states. The calculation results indicate that the shapes and energy levels of the highest occupied molecular orbitals (HOMOs), lowest unoccupied molecular orbitals (LUMOs), and LUMOs+1 for the monoanion and dianion forms are similar and thus DCF-MPYA and FL exhibit almost the same luminescence properties. Finally, DCF-MPYA and FL with low toxicity were used in confocal and time-resolved fluorescence imaging. Our construction strategy will be beneficial for developing more fluorescein derivatives with TADF in the future. Compounds DCF-MPYA and FL with microsecond scale lifetimes were obtained by fine tuning the substituents' structure on the basis of a fluorescein derivative with thermally activated delayed fluorescence (TADF) properties.![]()
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Affiliation(s)
- Zhaoye Lv
- Key Lab of Textile Cleaning, Dalian Polytechnic University, #1 Qinggongyuan, Dalian 116034, P. R. China
| | - Jun Hou
- Key Lab of Textile Cleaning, Dalian Polytechnic University, #1 Qinggongyuan, Dalian 116034, P. R. China
| | - Junjie Yao
- Key Lab of Textile Cleaning, Dalian Polytechnic University, #1 Qinggongyuan, Dalian 116034, P. R. China
| | - Ye Yuan
- Key Lab of Textile Cleaning, Dalian Polytechnic University, #1 Qinggongyuan, Dalian 116034, P. R. China
| | - Yulan Qian
- Key Lab of Textile Cleaning, Dalian Polytechnic University, #1 Qinggongyuan, Dalian 116034, P. R. China
| | - Junyang Zhu
- Key Lab of Textile Cleaning, Dalian Polytechnic University, #1 Qinggongyuan, Dalian 116034, P. R. China
| | - Hongjuan Zhao
- Key Lab of Textile Cleaning, Dalian Polytechnic University, #1 Qinggongyuan, Dalian 116034, P. R. China
| | - Xiaoqing Xiong
- Key Lab of Textile Cleaning, Dalian Polytechnic University, #1 Qinggongyuan, Dalian 116034, P. R. China
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, 2 Linggong Road, Dalian 116024, P. R. China
| | - Chengqi Jiao
- School of Chemistry and Chemical Engineering, Liaoning Normal University, 850 Huanghe Road, Dalian 116029, P. R. China
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39
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Shi Y, Wang K, Zhang S, Fan X, Tsuchiya Y, Lee Y, Dai G, Chen J, Zheng C, Xiong S, Ou X, Yu J, Jie J, Lee C, Adachi C, Zhang X. Characterizing the Conformational Distribution in an Amorphous Film of an Organic Emitter and Its Application in a “Self‐Doping” Organic Light‐Emitting Diode. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202108943] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Yi‐Zhong Shi
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices Joint International Research Laboratory of Carbon-Based Functional Materials and Devices Soochow University 199 Ren'ai Road Suzhou 215123 Jiangsu PR China
| | - Kai Wang
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices Joint International Research Laboratory of Carbon-Based Functional Materials and Devices Soochow University 199 Ren'ai Road Suzhou 215123 Jiangsu PR China
- Center for Organic Photonics and Electronics Research (OPERA) and Department of Applied Chemistry Kyushu University 744 Motooka, Nishi Fukuoka 819-0395 Japan
| | - Shao‐Li Zhang
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices Joint International Research Laboratory of Carbon-Based Functional Materials and Devices Soochow University 199 Ren'ai Road Suzhou 215123 Jiangsu PR China
| | - Xiao‐Chun Fan
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices Joint International Research Laboratory of Carbon-Based Functional Materials and Devices Soochow University 199 Ren'ai Road Suzhou 215123 Jiangsu PR China
| | - Youichi Tsuchiya
- Center for Organic Photonics and Electronics Research (OPERA) and Department of Applied Chemistry Kyushu University 744 Motooka, Nishi Fukuoka 819-0395 Japan
- JST, ERATO Adachi Molecular Exciton Engineering Project, Fukuoka Center for Organic Photonics and Electronics Research (OPERA) Kyushu University 744 Motooka, Nishi Fukuoka 819-0395 Japan
- International Institute for Carbon Neutral Energy Research (WPI-I2CNER) Kyushu University 744 Motooka, Nishi Fukuoka 819-0395 Japan
| | - Yi‐Ting Lee
- Center for Organic Photonics and Electronics Research (OPERA) and Department of Applied Chemistry Kyushu University 744 Motooka, Nishi Fukuoka 819-0395 Japan
| | - Gao‐Le Dai
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices Joint International Research Laboratory of Carbon-Based Functional Materials and Devices Soochow University 199 Ren'ai Road Suzhou 215123 Jiangsu PR China
| | - Jia‐Xiong Chen
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices Joint International Research Laboratory of Carbon-Based Functional Materials and Devices Soochow University 199 Ren'ai Road Suzhou 215123 Jiangsu PR China
- Center of Super-Diamond and Advanced Films (COSDAF) and Department of Chemistry City University of Hong Kong Hong Kong SAR P. R. China
| | - Cai‐Jun Zheng
- School of Optoelectronic Information University of Electronic Science and Technology of China (UESTC) Chengdu Sichuan 610054 P. R. China
| | - Shi‐Yun Xiong
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices Joint International Research Laboratory of Carbon-Based Functional Materials and Devices Soochow University 199 Ren'ai Road Suzhou 215123 Jiangsu PR China
| | - Xue‐Mei Ou
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices Joint International Research Laboratory of Carbon-Based Functional Materials and Devices Soochow University 199 Ren'ai Road Suzhou 215123 Jiangsu PR China
| | - Jia Yu
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices Joint International Research Laboratory of Carbon-Based Functional Materials and Devices Soochow University 199 Ren'ai Road Suzhou 215123 Jiangsu PR China
| | - Jian‐Sheng Jie
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices Joint International Research Laboratory of Carbon-Based Functional Materials and Devices Soochow University 199 Ren'ai Road Suzhou 215123 Jiangsu PR China
| | - Chun‐Sing Lee
- Center of Super-Diamond and Advanced Films (COSDAF) and Department of Chemistry City University of Hong Kong Hong Kong SAR P. R. China
| | - Chihaya Adachi
- Center for Organic Photonics and Electronics Research (OPERA) and Department of Applied Chemistry Kyushu University 744 Motooka, Nishi Fukuoka 819-0395 Japan
- JST, ERATO Adachi Molecular Exciton Engineering Project, Fukuoka Center for Organic Photonics and Electronics Research (OPERA) Kyushu University 744 Motooka, Nishi Fukuoka 819-0395 Japan
- International Institute for Carbon Neutral Energy Research (WPI-I2CNER) Kyushu University 744 Motooka, Nishi Fukuoka 819-0395 Japan
| | - Xiao‐Hong Zhang
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices Joint International Research Laboratory of Carbon-Based Functional Materials and Devices Soochow University 199 Ren'ai Road Suzhou 215123 Jiangsu PR China
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40
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Fang F, Zhu L, Li M, Song Y, Sun M, Zhao D, Zhang J. Thermally Activated Delayed Fluorescence Material: An Emerging Class of Metal-Free Luminophores for Biomedical Applications. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2102970. [PMID: 34705318 PMCID: PMC8693050 DOI: 10.1002/advs.202102970] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 08/27/2021] [Indexed: 05/06/2023]
Abstract
The development of simple, efficient, and biocompatible organic luminescent molecules is of great significance to the clinical transformation of biomaterials. In recent years, purely organic thermally activated delayed fluorescence (TADF) materials with an extremely small single-triplet energy gap (ΔEST ) have been considered as the most promising new-generation electroluminescence emitters, which is an enormous breakthrough in organic optoelectronics. By merits of the unique photophysical properties, high structure flexibility, and reduced health risks, such metal-free TADF luminophores have attracted tremendous attention in biomedical fields, including conventional fluorescence imaging, time-resolved imaging and sensing, and photodynamic therapy. However, there is currently no systematic summary of the TADF materials for biomedical applications, which is presented in this review. Besides a brief introduction of the major developments of TADF material, the typical TADF mechanisms and fundamental principles on design strategies of TADF molecules and nanomaterials are subsequently described. Importantly, a specific emphasis is placed on the discussion of TADF materials for various biomedical applications. Finally, the authors make a forecast of the remaining challenges and future developments. This review provides insightful perspectives and clear prospects towards the rapid development of TADF materials in biomedicine, which will be highly valuable to exploit new luminescent materials.
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Affiliation(s)
- Fang Fang
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life SciencesBeijing Institute of TechnologyBeijing100081P. R. China
| | - Lin Zhu
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life SciencesBeijing Institute of TechnologyBeijing100081P. R. China
| | - Min Li
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life SciencesBeijing Institute of TechnologyBeijing100081P. R. China
| | - Yueyue Song
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life SciencesBeijing Institute of TechnologyBeijing100081P. R. China
| | - Meng Sun
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life SciencesBeijing Institute of TechnologyBeijing100081P. R. China
| | - Dongxu Zhao
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life SciencesBeijing Institute of TechnologyBeijing100081P. R. China
| | - Jinfeng Zhang
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life SciencesBeijing Institute of TechnologyBeijing100081P. R. China
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Shi YZ, Wang K, Zhang SL, Fan XC, Tsuchiya Y, Lee YT, Dai GL, Chen JX, Zheng CJ, Xiong SY, Ou XM, Yu J, Jie JS, Lee CS, Adachi C, Zhang XH. Characterizing the Conformational Distribution in an Amorphous Film of an Organic Emitter and Its Application in a "Self-Doping" Organic Light-Emitting Diode. Angew Chem Int Ed Engl 2021; 60:25878-25883. [PMID: 34585471 DOI: 10.1002/anie.202108943] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Indexed: 11/05/2022]
Abstract
The conformational distribution and mutual interconversion of thermally activated delayed fluorescence (TADF) emitters significantly affect the exciton utilization. However, their influence on the photophysics in amorphous film states is still not known due to the lack of a suitable quantitative analysis method. Herein, we used temperature-dependent time-resolved photoluminescence spectroscopy to quantitatively measure the relative populations of the conformations of a TADF emitter for the first time. We further propose a new concept of "self-doping" for realizing high-efficiency nondoped OLEDs. Interestingly, this "compositionally" pure film actually behaves as a film with a dopant (quasi-equatorial form) in a matrix (quasi-axial form). The concentration-induced quenching that may occur at high concentrations is thus expected to be effectively relieved. The "self-doping" OLED prepared with the newly developed TADF emitter TP2P-PXZ as a neat emitting layer realizes a high maximum external quantum efficiency of 25.4 % and neglectable efficiency roll-off.
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Affiliation(s)
- Yi-Zhong Shi
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Joint International Research Laboratory of Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, PR China
| | - Kai Wang
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Joint International Research Laboratory of Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, PR China.,Center for Organic Photonics and Electronics Research (OPERA) and Department of Applied Chemistry, Kyushu University, 744 Motooka, Nishi, Fukuoka, 819-0395, Japan
| | - Shao-Li Zhang
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Joint International Research Laboratory of Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, PR China
| | - Xiao-Chun Fan
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Joint International Research Laboratory of Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, PR China
| | - Youichi Tsuchiya
- Center for Organic Photonics and Electronics Research (OPERA) and Department of Applied Chemistry, Kyushu University, 744 Motooka, Nishi, Fukuoka, 819-0395, Japan.,JST, ERATO Adachi Molecular Exciton Engineering Project, Fukuoka Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, 744 Motooka, Nishi, Fukuoka, 819-0395, Japan.,International Institute for Carbon Neutral Energy Research (WPI-I2CNER), Kyushu University, 744 Motooka, Nishi, Fukuoka, 819-0395, Japan
| | - Yi-Ting Lee
- Center for Organic Photonics and Electronics Research (OPERA) and Department of Applied Chemistry, Kyushu University, 744 Motooka, Nishi, Fukuoka, 819-0395, Japan
| | - Gao-Le Dai
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Joint International Research Laboratory of Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, PR China
| | - Jia-Xiong Chen
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Joint International Research Laboratory of Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, PR China.,Center of Super-Diamond and Advanced Films (COSDAF) and Department of Chemistry, City University of Hong Kong, Hong Kong SAR, P. R. China
| | - Cai-Jun Zheng
- School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu, Sichuan, 610054, P. R. China
| | - Shi-Yun Xiong
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Joint International Research Laboratory of Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, PR China
| | - Xue-Mei Ou
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Joint International Research Laboratory of Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, PR China
| | - Jia Yu
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Joint International Research Laboratory of Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, PR China
| | - Jian-Sheng Jie
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Joint International Research Laboratory of Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, PR China
| | - Chun-Sing Lee
- Center of Super-Diamond and Advanced Films (COSDAF) and Department of Chemistry, City University of Hong Kong, Hong Kong SAR, P. R. China
| | - Chihaya Adachi
- Center for Organic Photonics and Electronics Research (OPERA) and Department of Applied Chemistry, Kyushu University, 744 Motooka, Nishi, Fukuoka, 819-0395, Japan.,JST, ERATO Adachi Molecular Exciton Engineering Project, Fukuoka Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, 744 Motooka, Nishi, Fukuoka, 819-0395, Japan.,International Institute for Carbon Neutral Energy Research (WPI-I2CNER), Kyushu University, 744 Motooka, Nishi, Fukuoka, 819-0395, Japan
| | - Xiao-Hong Zhang
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Joint International Research Laboratory of Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, PR China
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Roy B, Maisuls I, Zhang J, Niemeyer FC, Rizzo F, Wölper C, Daniliuc CG, Tang BZ, Strassert C, Voskuhl J. Mapping the regioisomeric space and visible color range of purely organic dual emitters with ultralong phosphorescence components: From violet to red towards pure white-light. Angew Chem Int Ed Engl 2021; 61:e202111805. [PMID: 34693600 PMCID: PMC9299909 DOI: 10.1002/anie.202111805] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/12/2021] [Indexed: 11/25/2022]
Abstract
We mapped the entire visible range of the electromagnetic spectrum and achieved white light emission (CIE: 0.31, 0.34) by combining the intrinsic ns‐fluorescence with ultralong ms‐phosphorescence from purely organic dual emitters. We realized small molecular materials showing high photoluminescence quantum yields (ΦL) in the solid state at room temperature, achieved by active exploration of the regioisomeric substitution space. Chromophore stacking‐supported stabilization of triplet excitons with assistance from enhanced intersystem crossing channels in the crystalline state played the primary role for the ultra‐long phosphorescence. This strategy covers the entire visible spectrum, based on organic phosphorescent emitters with versatile regioisomeric substitution patterns, and provides a single molecular source of white light with long lifetime (up to 163.5 ms) for the phosphorescent component, and high overall photoluminescence quantum yields (up to ΦL=20 %).
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Affiliation(s)
- Bibhisan Roy
- University of Duisburg-Essen: Universitat Duisburg-Essen, Faculty of Chemistry (Organic Chemistry) and Center for Nanointegration (CENIDE), GERMANY
| | - Iván Maisuls
- WWU Münster: Westfalische Wilhelms-Universitat Munster, Institut für anorganische und analytische Chemie, CeNTech, CiMIC, SoN, GERMANY
| | - Jianyu Zhang
- Hong Kong University: University of Hong Kong, Department of Chemistry, HONG KONG
| | - Felix C Niemeyer
- University of Duisburg-Essen: Universitat Duisburg-Essen, Faculty of Chemistry (orgnaic Chemsitry) and Center for Nanointegration (CENIDE), GERMANY
| | - Fabio Rizzo
- WWU Münster: Westfalische Wilhelms-Universitat Munster, Organisch Chemisches Institut, GERMANY
| | - Christoph Wölper
- University of Duisburg-Essen: Universitat Duisburg-Essen, Institute for Inorganic Chemsity and Center for Nanointegation (CENIDE), GERMANY
| | - Constantin G Daniliuc
- WWU Münster: Westfalische Wilhelms-Universitat Munster, Organisch Chemisches Institut, GERMANY
| | - Ben Zhong Tang
- Hong Kong University: University of Hong Kong, Department of Chemistry, HONG KONG
| | - Cristian Strassert
- WWU Münster: Westfalische Wilhelms-Universitat Munster, Institut für anorganische und analytische Chemie, CeNTech, CiMIC, SON, GERMANY
| | - Jens Voskuhl
- Universitat Duisburg-Essen, Institute of organic chemistry, Universitätsstraße 7, 45117, Essen, GERMANY
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43
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Nakae T, Nishio M, Usuki T, Ikeya M, Nishimoto C, Ito S, Nishihara H, Hattori M, Hayashi S, Yamada T, Yamanoi Y. Luminescent Behavior Elucidation of a Disilane‐Bridged D–A–D Triad Composed of Phenothiazine and Thienopyrazine. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202108089] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Toyotaka Nakae
- Department of Chemistry School of Science The University of Tokyo 7-3-1 Hongo, Bunkyo-ku Tokyo 113-0033 Japan
| | - Masaki Nishio
- Department of Chemistry School of Science The University of Tokyo 7-3-1 Hongo, Bunkyo-ku Tokyo 113-0033 Japan
| | - Tsukasa Usuki
- Department of Chemistry School of Science The University of Tokyo 7-3-1 Hongo, Bunkyo-ku Tokyo 113-0033 Japan
| | - Minako Ikeya
- Department of Chemistry and Life Science Graduate School of Engineering Science Yokohama National University 79-5 Tokiwadai, Hodogaya-ku Yokohama Kanagawa 240-8501 Japan
| | - Chika Nishimoto
- Department of Chemistry and Life Science Graduate School of Engineering Science Yokohama National University 79-5 Tokiwadai, Hodogaya-ku Yokohama Kanagawa 240-8501 Japan
| | - Suguru Ito
- Department of Chemistry and Life Science Graduate School of Engineering Science Yokohama National University 79-5 Tokiwadai, Hodogaya-ku Yokohama Kanagawa 240-8501 Japan
| | - Hiroshi Nishihara
- Research Center for Science and Technology Tokyo University of Science 2641 Yamazaki, Noda-shi Chiba 278-8510 Japan
| | - Mineyuki Hattori
- National Institute of Advanced Industrial Science and Technology AIST Central 5, 1-1-1 Higashi Tsukuba Ibaraki 305-8565 Japan
| | - Shigenobu Hayashi
- National Institute of Advanced Industrial Science and Technology AIST Central 5, 1-1-1 Higashi Tsukuba Ibaraki 305-8565 Japan
| | - Teppei Yamada
- Department of Chemistry School of Science The University of Tokyo 7-3-1 Hongo, Bunkyo-ku Tokyo 113-0033 Japan
| | - Yoshinori Yamanoi
- Department of Chemistry School of Science The University of Tokyo 7-3-1 Hongo, Bunkyo-ku Tokyo 113-0033 Japan
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44
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Nakae T, Nishio M, Usuki T, Ikeya M, Nishimoto C, Ito S, Nishihara H, Hattori M, Hayashi S, Yamada T, Yamanoi Y. Luminescent Behavior Elucidation of a Disilane-Bridged D-A-D Triad Composed of Phenothiazine and Thienopyrazine. Angew Chem Int Ed Engl 2021; 60:22871-22878. [PMID: 34427025 DOI: 10.1002/anie.202108089] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Indexed: 12/28/2022]
Abstract
A σ-π extended aryldisilane, comprising a thienopyrazine group as an acceptor fragment and phenothiazine groups as the donor moiety, has been prepared through the introduction of two Si-Si bridges (compound 1). X-ray diffraction analysis determined the crystal structure of 1, and experimental and theoretical approaches investigated its optical properties. Solvatochromic studies revealed the dual emission of 1 in all solvents tested. Compound 1 also exhibited fluorescence in the solid state upon excitation with a hand-held UV lamp, as well as mechanochromic luminescent properties. The packing mode in the crystal structure, variation of phenothiazine conformation, morphological changes between crystalline and amorphous phases are the major factors showing reversible fluorescence under external stimuli. A theoretical conformer study found that 1 exists in distinct conformational groups differing in Gibbs free energy by less than 3 kcal mol-1 . The conformer in the crystalline state of 1 can promote the complete separation of the HOMO and LUMO between the phenothiazine donor and the thienopyrazine acceptor, linked by the disilane linker. HOMO-LUMO energy transition in the crystalline state is forbidden due to the lack of frontier orbital overlap. Crystalline state emission showed LUMO → HOMO-1 transition (locally excited (LE) state). In the amorphous state, the partial presence of quasi-axial conformers allows intramolecular charge-transfer type emission via energy transfer from dominant quasi-equatorial conformers. The strategy proposed in this work provides important guidance for developing stimuli-responsive materials with controlled excited states.
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Affiliation(s)
- Toyotaka Nakae
- Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Masaki Nishio
- Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Tsukasa Usuki
- Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Minako Ikeya
- Department of Chemistry and Life Science, Graduate School of Engineering Science, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama, Kanagawa, 240-8501, Japan
| | - Chika Nishimoto
- Department of Chemistry and Life Science, Graduate School of Engineering Science, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama, Kanagawa, 240-8501, Japan
| | - Suguru Ito
- Department of Chemistry and Life Science, Graduate School of Engineering Science, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama, Kanagawa, 240-8501, Japan
| | - Hiroshi Nishihara
- Research Center for Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda-shi, Chiba, 278-8510, Japan
| | - Mineyuki Hattori
- National Institute of Advanced Industrial Science and Technology, AIST Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan
| | - Shigenobu Hayashi
- National Institute of Advanced Industrial Science and Technology, AIST Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan
| | - Teppei Yamada
- Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Yoshinori Yamanoi
- Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
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45
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Drummond BH, Aizawa N, Zhang Y, Myers WK, Xiong Y, Cooper MW, Barlow S, Gu Q, Weiss LR, Gillett AJ, Credgington D, Pu YJ, Marder SR, Evans EW. Electron spin resonance resolves intermediate triplet states in delayed fluorescence. Nat Commun 2021; 12:4532. [PMID: 34312394 PMCID: PMC8313702 DOI: 10.1038/s41467-021-24612-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 06/22/2021] [Indexed: 11/09/2022] Open
Abstract
Molecular organic fluorophores are currently used in organic light-emitting diodes, though non-emissive triplet excitons generated in devices incorporating conventional fluorophores limit the efficiency. This limit can be overcome in materials that have intramolecular charge-transfer excitonic states and associated small singlet-triplet energy separations; triplets can then be converted to emissive singlet excitons resulting in efficient delayed fluorescence. However, the mechanistic details of the spin interconversion have not yet been fully resolved. We report transient electron spin resonance studies that allow direct probing of the spin conversion in a series of delayed fluorescence fluorophores with varying energy gaps between local excitation and charge-transfer triplet states. The observation of distinct triplet signals, unusual in transient electron spin resonance, suggests that multiple triplet states mediate the photophysics for efficient light emission in delayed fluorescence emitters. We reveal that as the energy separation between local excitation and charge-transfer triplet states decreases, spin interconversion changes from a direct, singlet-triplet mechanism to an indirect mechanism involving intermediate states.
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Affiliation(s)
- Bluebell H Drummond
- Department of Physics, Cavendish Laboratory, J J Thomson Avenue, University of Cambridge, Cambridge, UK
- Centre for Advanced Electron Spin Resonance (CAESR), Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, Oxford, UK
| | - Naoya Aizawa
- RIKEN Center for Emergent Matter Science (CEMS), Saitama, Japan
| | - Yadong Zhang
- School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, GA, USA
| | - William K Myers
- Centre for Advanced Electron Spin Resonance (CAESR), Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, Oxford, UK
| | - Yao Xiong
- School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, GA, USA
| | - Matthew W Cooper
- School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, GA, USA
| | - Stephen Barlow
- School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, GA, USA
| | - Qinying Gu
- Department of Physics, Cavendish Laboratory, J J Thomson Avenue, University of Cambridge, Cambridge, UK
| | - Leah R Weiss
- Department of Physics, Cavendish Laboratory, J J Thomson Avenue, University of Cambridge, Cambridge, UK
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, USA
| | - Alexander J Gillett
- Department of Physics, Cavendish Laboratory, J J Thomson Avenue, University of Cambridge, Cambridge, UK
| | - Dan Credgington
- Department of Physics, Cavendish Laboratory, J J Thomson Avenue, University of Cambridge, Cambridge, UK
| | - Yong-Jin Pu
- RIKEN Center for Emergent Matter Science (CEMS), Saitama, Japan
| | - Seth R Marder
- School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, GA, USA
| | - Emrys W Evans
- Department of Physics, Cavendish Laboratory, J J Thomson Avenue, University of Cambridge, Cambridge, UK.
- Department of Chemistry, Swansea University, Swansea, UK.
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46
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Yang L, Horton JT, Payne MC, Penfold TJ, Cole DJ. Modeling Molecular Emitters in Organic Light-Emitting Diodes with the Quantum Mechanical Bespoke Force Field. J Chem Theory Comput 2021; 17:5021-5033. [PMID: 34264669 DOI: 10.1021/acs.jctc.1c00135] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Combined molecular dynamics (MD) and quantum mechanics (QM) simulation procedures have gained popularity in modeling the spectral properties of functional organic molecules. However, the potential energy surfaces used to propagate long-time scale dynamics in these simulations are typically described using general, transferable force fields designed for organic molecules in their electronic ground states. These force fields do not typically include spectroscopic data in their training, and importantly, there is no general protocol for including changes in geometry or intermolecular interactions with the environment that may occur upon electronic excitation. In this work, we show that parameters tailored for thermally activated delayed fluorescence (TADF) emitters used in organic light-emitting diodes (OLEDs), in both their ground and electronically excited states, can be readily derived from a small number of QM calculations using the QUBEKit (QUantum mechanical BEspoke toolKit) software and improve the overall accuracy of these simulations.
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Affiliation(s)
- Lupeng Yang
- TCM Group, Cavendish Laboratory, 19 JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Joshua T Horton
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, United Kingdom
| | - Michael C Payne
- TCM Group, Cavendish Laboratory, 19 JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Thomas J Penfold
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, United Kingdom
| | - Daniel J Cole
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, United Kingdom
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47
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Muniyasamy H, Chinnadurai C, Nelson M, Veeramanoharan A, Sepperumal M, Ayyanar S. Synthesis of C 3-Symmetric Triazine-Based Derivatives: Study of their AIEE, Mechanochromic Behaviors, and Detection of Picric Acid and Uric Acid in Aqueous Medium. Ind Eng Chem Res 2021. [DOI: 10.1021/acs.iecr.1c00827] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Harikrishnan Muniyasamy
- Supramolecular and Organometallic Chemistry Laboratory, Department of Inorganic Chemistry, School of Chemistry, Madurai Kamaraj University, Madurai, Tamilnadu 625 021, India
| | - Chithiraikumar Chinnadurai
- Supramolecular and Organometallic Chemistry Laboratory, Department of Inorganic Chemistry, School of Chemistry, Madurai Kamaraj University, Madurai, Tamilnadu 625 021, India
| | - Malini Nelson
- Supramolecular and Organometallic Chemistry Laboratory, Department of Inorganic Chemistry, School of Chemistry, Madurai Kamaraj University, Madurai, Tamilnadu 625 021, India
| | - Ashokkumar Veeramanoharan
- Supramolecular and Organometallic Chemistry Laboratory, Department of Inorganic Chemistry, School of Chemistry, Madurai Kamaraj University, Madurai, Tamilnadu 625 021, India
| | - Murugesan Sepperumal
- Supramolecular and Organometallic Chemistry Laboratory, Department of Inorganic Chemistry, School of Chemistry, Madurai Kamaraj University, Madurai, Tamilnadu 625 021, India
| | - Siva Ayyanar
- Supramolecular and Organometallic Chemistry Laboratory, Department of Inorganic Chemistry, School of Chemistry, Madurai Kamaraj University, Madurai, Tamilnadu 625 021, India
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48
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Barcenas G, Biaggne A, Mass OA, Wilson CK, Obukhova OM, Kolosova OS, Tatarets AL, Terpetschnig E, Pensack RD, Lee J, Knowlton WB, Yurke B, Li L. First-principles studies of substituent effects on squaraine dyes. RSC Adv 2021; 11:19029-19040. [PMID: 35478639 PMCID: PMC9033489 DOI: 10.1039/d1ra01377g] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 05/17/2021] [Indexed: 01/21/2023] Open
Abstract
Dye molecules that absorb light in the visible region are key components in many applications, including organic photovoltaics, biological fluorescent labeling, super-resolution microscopy, and energy transport. One family of dyes, known as squaraines, has received considerable attention recently due to their favorable electronic and photophysical properties. In addition, these dyes have a strong propensity for aggregation, which results in emergent materials properties, such as exciton delocalization. This will be of benefit in charge separation and energy transport along with fundamental studies in quantum information. Given the high structural tunability of squaraine dyes, it is possible that exciton delocalization could be tailored by modifying the substituents attached to the π-conjugated network. To date, limited theoretical studies have explored the role of substituent effects on the electronic and photophysical properties of squaraines in the context of DNA-templated dye aggregates and resultant excitonic behavior. We used ab initio theoretical methods to determine the effects of substituents on the electronic and photophysical properties for a series of nine different squaraine dyes. Solvation free energy was also investigated as an insight into changes in hydrophobic behavior from substituents. The role of molecular symmetry on these properties was also explored via conformation and substitution. We found that substituent effects are correlated with the empirical Hammett constant, which demonstrates their electron donating or electron withdrawing strength. Electron withdrawing groups were found to impact solvation free energy, transition dipole moment, static dipole difference, and absorbance more than electron donating groups. All substituents showed a redshift in absorption for the squaraine dye. In addition, solvation free energy increases with Hammett constant. This work represents a first step toward establishing design rules for dyes with desired properties for excitonic applications. Squaraine dyes are candidates for DNA-templated excitonic interactions. This work presents substituent effects on the electronic and photophysicalproperties of squaraine dyes and a correlation between empirical Hammettconstant and those properties.![]()
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Affiliation(s)
- German Barcenas
- Micron School of Materials Science and Engineering, Boise State University Boise ID 83725 USA
| | - Austin Biaggne
- Micron School of Materials Science and Engineering, Boise State University Boise ID 83725 USA
| | - Olga A Mass
- Micron School of Materials Science and Engineering, Boise State University Boise ID 83725 USA
| | - Christopher K Wilson
- Micron School of Materials Science and Engineering, Boise State University Boise ID 83725 USA
| | - Olena M Obukhova
- SSI "Institute for Single Crystals" of National Academy of Sciences of Ukraine Kharkov 61072 Ukraine
| | - Olga S Kolosova
- SSI "Institute for Single Crystals" of National Academy of Sciences of Ukraine Kharkov 61072 Ukraine
| | - Anatoliy L Tatarets
- SSI "Institute for Single Crystals" of National Academy of Sciences of Ukraine Kharkov 61072 Ukraine.,SETA BioMedicals Urbana IL 61802 USA
| | | | - Ryan D Pensack
- Micron School of Materials Science and Engineering, Boise State University Boise ID 83725 USA
| | - Jeunghoon Lee
- Micron School of Materials Science and Engineering, Boise State University Boise ID 83725 USA .,Department of Chemistry and Biochemistry, Boise State University Boise ID 83725 USA
| | - William B Knowlton
- Micron School of Materials Science and Engineering, Boise State University Boise ID 83725 USA .,Department of Electrical and Computer Engineering, Boise State University Boise ID 83725 USA
| | - Bernard Yurke
- Micron School of Materials Science and Engineering, Boise State University Boise ID 83725 USA .,Department of Electrical and Computer Engineering, Boise State University Boise ID 83725 USA
| | - Lan Li
- Micron School of Materials Science and Engineering, Boise State University Boise ID 83725 USA .,Center for Advanced Energy Studies Idaho Falls ID 83401 USA
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49
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Wada Y, Nakagawa H, Kaji H. Acceleration of Reverse Intersystem Crossing using Different Types of Charge Transfer States. Chem Asian J 2021; 16:1073-1076. [PMID: 33742542 DOI: 10.1002/asia.202100091] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 03/17/2021] [Indexed: 11/09/2022]
Abstract
There is a need to boost the rate constant of reverse intersystem crossing (kRISC ) in thermally activated delayed fluorescence (TADF) materials for applications to organic light-emitting diodes. Recently, energy level matching of the locally excited state (LE) and charge transfer state (CT) has been reported to enhance kRISC . In this study, we conceptually demonstrate that kRISC can be improved even between CT states without LE states, through the use of different types of CT states. On the basis of this concept, we design a new compound, named DMAC-bPmT, where two phenyl groups of a well-known TADF material DMAC-TRZ are substituted by pyrimidine groups. Theoretical calculations indicated that the energy levels of the different CT states of DMAC-bPmT are very close and enhanced spin orbit coupling may be expected between them. As predicted, DMAC-bPmT experimentally exhibited a kRISC three times as high as that of DMAC-TRZ.
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Affiliation(s)
- Yoshimasa Wada
- Institute for Chemical Research Kyoto University, Uji, Kyoto, 611-0011, Japan
| | - Hiromichi Nakagawa
- Institute for Chemical Research Kyoto University, Uji, Kyoto, 611-0011, Japan
| | - Hironori Kaji
- Institute for Chemical Research Kyoto University, Uji, Kyoto, 611-0011, Japan
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50
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Wada Y, Wakisaka Y, Kaji H. Efficient Direct Reverse Intersystem Crossing between Charge Transfer-Type Singlet and Triplet States in a Purely Organic Molecule. Chemphyschem 2021; 22:625-632. [PMID: 33586264 DOI: 10.1002/cphc.202001013] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 02/11/2021] [Indexed: 11/07/2022]
Abstract
In the field of organic light-emitting diodes, thermally activated delayed fluorescence (TADF) materials have achieved great performance. The key factor for this performance is the small energy gap (ΔEST ) between the lowest triplet (T1 ) and singlet excited (S1 ) states, which can be realized in a well-separated donor-acceptor system. Such systems are likely to possess similar charge transfer (CT)-type T1 and S1 states. Recent investigations have suggested that the intervention of other type-states, such as locally excited triplet state(s), is necessary for efficient reverse intersystem crossing (RISC). Here, we theoretically and experimentally demonstrate that our blue TADF material exhibits efficient RISC even between singlet CT and triplet CT states without any additional states. The key factor is dynamic flexibility of the torsion angle between the donor and acceptor, which enhances spin-orbit coupling even between the charge transfer-type T1 and S1 states, without sacrificing the small ΔEST . This results in excellent photoluminescence and electroluminescence performances in all the host materials we investigate, with sky-blue to deep-blue emissions. Among the hosts investigated, the deepest blue emission with CIE coordinates of (0.15, 0.16) and the highest EQEMAX of 23.9 % are achieved simultaneously.
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Affiliation(s)
- Yoshimasa Wada
- Institute for Chemical Research, Kyoto University, Uji, Kyoto, 611-0011, Japan
| | - Yasuaki Wakisaka
- Institute for Chemical Research, Kyoto University, Uji, Kyoto, 611-0011, Japan
| | - Hironori Kaji
- Institute for Chemical Research, Kyoto University, Uji, Kyoto, 611-0011, Japan
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