1
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Kim H, Lee K, Kim JH, Kim WY. Deep Learning-Based Chemical Similarity for Accelerated Organic Light-Emitting Diode Materials Discovery. J Chem Inf Model 2024; 64:677-689. [PMID: 38270063 DOI: 10.1021/acs.jcim.3c01747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2024]
Abstract
Thermally activated delayed fluorescence (TADF) material has attracted great attention as a promising metal-free organic light-emitting diode material with a high theoretical efficiency. To accelerate the discovery of novel TADF materials, computer-aided material design strategies have been developed. However, they have clear limitations due to the accessibility of only a few computationally tractable properties. Here, we propose TADF-likeness, a quantitative score to evaluate the TADF potential of molecules based on a data-driven concept of chemical similarity to existing TADF molecules. We used a deep autoencoder to characterize the common features of existing TADF molecules with common chemical descriptors. The score was highly correlated with the four essential electronic properties of TADF molecules and had a high success rate in large-scale virtual screening of millions of molecules to identify promising candidates at almost no cost, validating its feasibility for accelerating TADF discovery. The concept of TADF-likeness can be extended to other fields of materials discovery.
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Affiliation(s)
- Hyeonsu Kim
- Department of Chemistry, Korea Advanced Institute of Science & Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Kyunghoon Lee
- Department of Chemistry, Korea Advanced Institute of Science & Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Jun Hyeong Kim
- Department of Chemistry, Korea Advanced Institute of Science & Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Woo Youn Kim
- Department of Chemistry, Korea Advanced Institute of Science & Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
- AI Institute, Korea Advanced Institute of Science & Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
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2
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Song J, Guan Y, Wang C, Li W, Bao X, Niu L. Effect of Conductive Polymers PEDOT:PSS on Exciton Recombination and Conversion in Doped-Type BioLEDs. Polymers (Basel) 2023; 15:3275. [PMID: 37571169 PMCID: PMC10421517 DOI: 10.3390/polym15153275] [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: 07/06/2023] [Revised: 07/28/2023] [Accepted: 07/29/2023] [Indexed: 08/13/2023] Open
Abstract
Although the effect of the conductive polymers PEDOT:PSS on the electroluminescence performance of doped-type organic light-emitting diodes (OLEDs) has been studied, the process of PEDOT:PSS regulation of exciton recombination region and concentration within the deoxyribonucleic acid (DNA)-based doped-type BioLEDs is still obscure. In this study, we fabricated Bio-devices with and without PEDOT:PSS using varying spin-coating speeds of PEDOT:PSS. The Alq3:Rubrene-based BioLEDs achieve higher luminance (44,010 cd/m2) and higher luminance efficiency (8.1 cd/A), which are increased by 186% and 478%, respectively, compared to the reference BioLEDs without PEDOT:PSS. Similarly, the maximum luminance and efficiency of blue TCTA:TPBi exciplex-type BioLEDs are increased by 224% and 464%. In particular, our findings reveal that with an increasing thickness of PEDOT:PSS, the region of exciton recombination shifts towards the interface between the emitting layer (EML) and the hole transport layer (HTL). Meanwhile, the concentration of singlet exciton (S1,Rub) and triplet exciton (T1,Rub) increases, and the triplet-triplet annihilation (TTA) process is enhanced, resulting in the enhanced luminescence and efficiency of the devices. Accordingly, we provide a possible idea for achieving high performance doped-type BioLEDs by adding conductive polymers PEDOT:PSS, and revealing the effect of exciton recombination and conversion in BioLEDs given different PEDOT:PSS thicknesses.
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Affiliation(s)
| | - Yunxia Guan
- College of Physics and Electronic Engineering, Chongqing Normal University, Chongqing 401331, China; (J.S.); (C.W.); (W.L.); (X.B.)
| | | | | | | | - Lianbin Niu
- College of Physics and Electronic Engineering, Chongqing Normal University, Chongqing 401331, China; (J.S.); (C.W.); (W.L.); (X.B.)
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3
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Cai X, Xu Y, Pan Y, Li L, Pu Y, Zhuang X, Li C, Wang Y. Solution-Processable Pure-Red Multiple Resonance-induced Thermally Activated Delayed Fluorescence Emitter for Organic Light-Emitting Diode with External Quantum Efficiency over 20 . Angew Chem Int Ed Engl 2023; 62:e202216473. [PMID: 36511099 DOI: 10.1002/anie.202216473] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 12/12/2022] [Accepted: 12/13/2022] [Indexed: 12/15/2022]
Abstract
Developing solution-processable red organic light-emitting diodes (OLEDs) with high color purity and efficiency based on multiple resonance thermally activated delayed fluorescence (MR-TADF) is a formidable challenge. Herein, by introducing auxiliary electron donor and acceptor moieties into the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) distributed positions of multiple resonance skeleton simultaneously, an effective strategy to obtain red MR-TADF emitters was represented. The proof-of-the-concept molecule BN-R exhibits a narrowband pure-red emission at 624 nm, with a high luminous efficiency of 94 % and a narrow bandwidth of 46 nm. Notably, the fabricated solution-processable pure-red OLED based on BN-R exhibits a state-of-the-art external quantum efficiency over 20 % with the Commission Internationale de I'Éclairage coordinates of (0.663, 0.337) and a long operational lifetime (LT50 ) of 1088 hours at an initial luminance of 1000 cd m-2 .
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Affiliation(s)
- Xinliang Cai
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Yincai Xu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Yue Pan
- Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education, School of Life Science, Jilin University, Changchun, 130012, P. R. China
| | - Linjie Li
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Yexuan Pu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Xuming Zhuang
- Jihua Laboratory, 28 Huandao South Road, Foshan, 528200, Guangdong Province, P. R. China
| | - Chenglong Li
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.,Chongqing Research Institute, Jilin University, Chongqing, 401120, P. R. China
| | - Yue Wang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.,Jihua Laboratory, 28 Huandao South Road, Foshan, 528200, Guangdong Province, P. R. China.,Jihua Hengye Electronic Materials CO. LTD., Foshan, 528200, Guangdong Province, P. R. China
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4
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Chang Q, Ma T, Ding W, Zhang L, Cheng X. Thiophene-benzothiadiazole based donor–acceptor–donor (D-A-D) bolaamphiphiles, self-assembly and photophysical properties. Supramol Chem 2021. [DOI: 10.1080/10610278.2021.1959036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Qing Chang
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education, Yunnan Research & Development Center for Natural Products, Yunnan University, Kunming, PR China
| | - Tao Ma
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education, Yunnan Research & Development Center for Natural Products, Yunnan University, Kunming, PR China
| | - Wei Ding
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education, Yunnan Research & Development Center for Natural Products, Yunnan University, Kunming, PR China
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5
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How do molecular interactions affect fluorescence behavior of AIEgens in solution and aggregate states? Sci China Chem 2021. [DOI: 10.1007/s11426-021-1083-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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6
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Zhang X, Wang P, Nie Y, Ma Q. Recent development of organic nanoemitter-based ECL sensing application. Trends Analyt Chem 2021. [DOI: 10.1016/j.trac.2021.116410] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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7
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Li Z, Yang D, Han C, Zhao B, Wang H, Man Y, Ma P, Chang P, Ma D, Xu H. Optimizing Charge Transfer and Out-Coupling of A Quasi-Planar Deep-Red TADF Emitter: towards Rec.2020 Gamut and External Quantum Efficiency beyond 30 . Angew Chem Int Ed Engl 2021; 60:14846-14851. [PMID: 33871909 DOI: 10.1002/anie.202103070] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 03/28/2021] [Indexed: 11/11/2022]
Abstract
Herein, we report a deep-red TADF emitter pCNQ-TPA, composed of quinoxaline-5,8-dicarbonitrile (pCNQ) acceptor and triphenylamine (TPA) donor. pCNQ-TPA supported its OLED with desired CIE coordinates of (0.69, 0.31) and the record maximum external quantum efficiency of 30.3 %, which is the best red TADF diode with Rec.2020 gamut for UHDTV. It is showed that through tuning pCNQ-TPA doping concentration, intra- and inter-molecular charge transfer are balanced to synchronously improve emission color saturation and TADF radiation, and remedy aggregation-induced quenching, rendering photoluminescence quantum yield (PLQY) reaching 90 % for deep-red emission peaked at ≈690 nm. Quasi-planar structure further endows pCNQ-TPA with an improved horizontal ratio of emitting dipole orientation, which increases light out-coupling ratio to 0.34 for achieving the state-of-the-art device efficiencies.
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Affiliation(s)
- Zhe Li
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, 150080, P. R. China
| | - Dezhi Yang
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou, 510640, P. R. China
| | - Chunmiao Han
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, 150080, P. R. China
| | - Bingjie Zhao
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, 150080, P. R. China
| | - Huiqin Wang
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, 150080, P. R. China
| | - Yi Man
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, 150080, P. R. China
| | - Peng Ma
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, 150080, P. R. China
| | - Peng Chang
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, 150080, P. R. China
| | - Dongge Ma
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou, 510640, P. R. China
| | - Hui Xu
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, 150080, P. R. China
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8
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Li Z, Yang D, Han C, Zhao B, Wang H, Man Y, Ma P, Chang P, Ma D, Xu H. Optimizing Charge Transfer and Out‐Coupling of A Quasi‐Planar Deep‐Red TADF Emitter: towards Rec.2020 Gamut and External Quantum Efficiency beyond 30 %. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202103070] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Zhe Li
- Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Heilongjiang University Harbin 150080 P. R. China
| | - Dezhi Yang
- Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and Devices South China University of Technology Guangzhou 510640 P. R. China
| | - Chunmiao Han
- Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Heilongjiang University Harbin 150080 P. R. China
| | - Bingjie Zhao
- Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Heilongjiang University Harbin 150080 P. R. China
| | - Huiqin Wang
- Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Heilongjiang University Harbin 150080 P. R. China
| | - Yi Man
- Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Heilongjiang University Harbin 150080 P. R. China
| | - Peng Ma
- Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Heilongjiang University Harbin 150080 P. R. China
| | - Peng Chang
- Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Heilongjiang University Harbin 150080 P. R. China
| | - Dongge Ma
- Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and Devices South China University of Technology Guangzhou 510640 P. R. China
| | - Hui Xu
- Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Heilongjiang University Harbin 150080 P. R. China
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9
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Zhao B, Wang H, Han C, Ma P, Li Z, Chang P, Xu H. Highly Efficient Deep‐Red Non‐Doped Diodes Based on a T‐Shape Thermally Activated Delayed Fluorescence Emitter. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202008885] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Bingjie Zhao
- Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Heilongjiang University Harbin Heilongjiang 150080 China
| | - Huiqin Wang
- Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Heilongjiang University Harbin Heilongjiang 150080 China
| | - Chunmiao Han
- Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Heilongjiang University Harbin Heilongjiang 150080 China
| | - Peng Ma
- Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Heilongjiang University Harbin Heilongjiang 150080 China
| | - Zhe Li
- Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Heilongjiang University Harbin Heilongjiang 150080 China
| | - Peng Chang
- Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Heilongjiang University Harbin Heilongjiang 150080 China
| | - Hui Xu
- Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Heilongjiang University Harbin Heilongjiang 150080 China
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10
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Zhao B, Wang H, Han C, Ma P, Li Z, Chang P, Xu H. Highly Efficient Deep-Red Non-Doped Diodes Based on a T-Shape Thermally Activated Delayed Fluorescence Emitter. Angew Chem Int Ed Engl 2020; 59:19042-19047. [PMID: 32697873 DOI: 10.1002/anie.202008885] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Indexed: 12/21/2022]
Abstract
Device simplification is of practical significance for organic light emitting diodes (OLEDs), and remains the great challenge for deep-red emitters. Herein, a deep-red thermally activated delayed fluorescence molecule (pTPA-DPPZ) is reported which features a T shaped structure containing two triphenylamine (TPA) donors, one either side of a planar dipyridophenazine (DPPZ) acceptor. The rational spatial arrangement of the functional groups leads to limited but sufficient molecular packing for effective carrier transport. The neat pTPA-DPPZ film achieves an around 90-fold improved radiation rate constant of 107 s-1 and the nearly unitary reverse intersystem crossing (RISC) efficiency, as well as accelerated emission decays for quenching suppression. The high radiation and RISC result in a photoluminescence quantum yield of 87 %. The bilayer OLED based on the pTPA-DPPZ emissive layer achieved the record external quantum efficiencies of 12.3 % for maximum and 10.4 % at 1000 nits, accompanied by the deep-red electroluminescence with the excellent color purity.
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Affiliation(s)
- Bingjie Zhao
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, Heilongjiang, 150080, China
| | - Huiqin Wang
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, Heilongjiang, 150080, China
| | - Chunmiao Han
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, Heilongjiang, 150080, China
| | - Peng Ma
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, Heilongjiang, 150080, China
| | - Zhe Li
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, Heilongjiang, 150080, China
| | - Peng Chang
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, Heilongjiang, 150080, China
| | - Hui Xu
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, Heilongjiang, 150080, China
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11
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Yuan P, Guo X, Qiao X, Ma D. Correlated magnetic field effects on carriers and excitons in single-carrier exciplex-based organic photodiodes. Phys Chem Chem Phys 2019; 21:26413-26419. [PMID: 31774087 DOI: 10.1039/c9cp05178c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Magnetic field effects in nonmagnetic organic semiconductors (OMFEs) are attracting increasing attention because of the fingerprint characteristics of their line shapes when they are used to analyze the dynamic processes of organic photodiodes. However, the origin and correlation of OMFEs on carriers and excitons are currently still major challenges for researchers. In this study, we strategically designed exciplex-based single-carrier devices to effectively separate carriers and excitons and investigate their OMFEs and relationships. It is found that the obvious positive magneto-conductance (MC) with illumination is not only related to the formation of charge transfer state (CT) excitons, but is also caused by the secondary recombination process between dissociated carriers from the photo-generated excitons and the injected carriers. Moreover, a negative MC appears under dark conditions, reflecting the intrinsic magnetic field effects on carrier transport. The relationships of the OMFEs with the excitons and carriers were further studied by measuring the incident-wavelength dependent photo-induced MC and the magneto-photoluminescence (MPL) of the exciplex films. The two films show similar amplitude-dependent curves, which are contributed by their donor-acceptor absorption properties. Moreover, the strong triplet-polaron annihilation (TPA) processes exhibited in this device afford different amplitude-dependent photo-induced MCs.
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Affiliation(s)
- Peisen Yuan
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, People's Republic of China.
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12
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Cao Y, Eng J, Penfold TJ. Excited State Intramolecular Proton Transfer Dynamics for Triplet Harvesting in Organic Molecules. J Phys Chem A 2019; 123:2640-2649. [DOI: 10.1021/acs.jpca.9b00813] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Y. Cao
- Chemistry- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, U.K
| | - J. Eng
- Chemistry- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, U.K
| | - T. J. Penfold
- Chemistry- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, U.K
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13
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Mohanty ME, Madhu C, Reddy VL, Paramasivam M, Bangal PR, Rao VJ. Direct observation of the rise of delayed fluorescence in dithienylbenzothiadiazole and its role in the excited state dynamics of a donor-acceptor-donor molecule. Phys Chem Chem Phys 2018; 19:9118-9127. [PMID: 28317965 DOI: 10.1039/c7cp00261k] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Dithienylbenzothiadiazole (DTBT) is used as a building block in several molecules having application in organic light emitting devices (OLED) and organic photovoltaic (OPV) devices. Delayed fluorescence (DF) is the preferred design principle employed currently in OLED research. DTBT has excellent delayed fluorescence properties which makes this moiety a potentially viable OLED material. Here, the dynamics of intersystem crossing (ISC) and reverse intersystem crossing (RISC) have been explored using fluorescence, phosphorescence, fluorescence lifetime and transient absorption measurements. Experimentally it is demonstrated that singlet and triplet states of DTBT are close lying or degenerate and after a certain time the molecules can stay in the singlet or the triplet state forming an equilibrium between the two states which hinders the identification of these two states that could be characterized by routine steady state fluorescence and phosphorescence studies. Similarly in OPV material research, DTBT is coupled with strong donors to form push-pull molecules to produce a prolonged charge separated state. In this study DTBT appended with carbazole at both ends (CDTBT) was used to study the dynamics of DTBT within a donor-acceptor-donor system. The study reveals similar kinds of ISC and RISC in CDTBT along with a competitive deactivation pathway of the singlet state and it was concluded to be through the formation of a charge separated species in CDTBT.
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Affiliation(s)
- Maneesha Esther Mohanty
- Crop Protection Chemicals Division, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India.
| | - Chakali Madhu
- Crop Protection Chemicals Division, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India.
| | - Vanammoole Lakshmi Reddy
- Crop Protection Chemicals Division, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India.
| | - Mahalingavelar Paramasivam
- Crop Protection Chemicals Division, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India.
| | - Prakriti Ranjan Bangal
- Inorganic and Physical Chemistry Division, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India.
| | - Vaidya Jayathirtha Rao
- Crop Protection Chemicals Division, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India.
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14
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Wong MY, Zysman-Colman E. Purely Organic Thermally Activated Delayed Fluorescence Materials for Organic Light-Emitting Diodes. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2017; 29:1605444. [PMID: 28256751 DOI: 10.1002/adma.201605444] [Citation(s) in RCA: 774] [Impact Index Per Article: 110.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Revised: 11/22/2016] [Indexed: 05/24/2023]
Abstract
The design of thermally activated delayed fluorescence (TADF) materials both as emitters and as hosts is an exploding area of research. The replacement of phosphorescent metal complexes with inexpensive organic compounds in electroluminescent (EL) devices that demonstrate comparable performance metrics is paradigm shifting, as these new materials offer the possibility of developing low-cost lighting and displays. Here, a comprehensive review of TADF materials is presented, with a focus on linking their optoelectronic behavior with the performance of the organic light-emitting diode (OLED) and related EL devices. TADF emitters are cross-compared within specific color ranges, with a focus on blue, green-yellow, orange-red, and white OLEDs. Organic small-molecule, dendrimer, polymer, and exciplex emitters are all discussed within this review, as is their use as host materials. Correlations are provided between the structure of the TADF materials and their optoelectronic properties. The success of TADF materials has ushered in the next generation of OLEDs.
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Affiliation(s)
- Michael Y Wong
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife, KY16 9ST, UK
| | - Eli Zysman-Colman
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife, KY16 9ST, UK
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15
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Deng J, Jia W, Chen Y, Liu D, Hu Y, Xiong Z. Guest concentration, bias current, and temperature-dependent sign inversion of magneto-electroluminescence in thermally activated delayed fluorescence devices. Sci Rep 2017; 7:44396. [PMID: 28295056 PMCID: PMC5353579 DOI: 10.1038/srep44396] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 02/07/2017] [Indexed: 11/18/2022] Open
Abstract
Non-emissive triplet excited states in devices that undergo thermally activated delayed fluorescence (TADF) can be up-converted to singlet excited states via reverse intersystem crossing (RISC), which leads to an enhanced electroluminescence efficiency. Exciton-based fluorescence devices always exhibit a positive magneto-electroluminescence (MEL) because intersystem crossing (ISC) can be suppressed effectively by an external magnetic field. Conversely, TADF devices should exhibit a negative MEL because RISC is suppressed by the external magnetic field. Intriguingly, we observed a positive MEL in TADF devices. Moreover, the sign of the MEL was either positive or negative, and depended on experimental conditions, including doping concentration, current density and temperature. The MEL observed from our TADF devices demonstrated that ISC in the host material and RISC in the guest material coexisted. These competing processes were affected by the experimental conditions, which led to the sign change of the MEL. This work gives important insight into the energy transfer processes and the evolution of excited states in TADF devices.
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Affiliation(s)
- Junquan Deng
- School of Physical Science and Technology, MOE Key Laboratory on Luminescence and Real-Time Analysis, Southwest University, Chongqing, 400715, P. R. China
| | - Weiyao Jia
- School of Physical Science and Technology, MOE Key Laboratory on Luminescence and Real-Time Analysis, Southwest University, Chongqing, 400715, P. R. China
| | - Yingbing Chen
- School of Physical Science and Technology, MOE Key Laboratory on Luminescence and Real-Time Analysis, Southwest University, Chongqing, 400715, P. R. China
| | - Dongyu Liu
- School of Physical Science and Technology, MOE Key Laboratory on Luminescence and Real-Time Analysis, Southwest University, Chongqing, 400715, P. R. China
| | - Yeqian Hu
- School of Physical Science and Technology, MOE Key Laboratory on Luminescence and Real-Time Analysis, Southwest University, Chongqing, 400715, P. R. China
| | - Zuhong Xiong
- School of Physical Science and Technology, MOE Key Laboratory on Luminescence and Real-Time Analysis, Southwest University, Chongqing, 400715, P. R. China
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16
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Affiliation(s)
- Yujun Xie
- Hubei Key Lab on Organic and Polymeric Opto-Electronic Materials, Department of Chemistry; Wuhan University; Wuhan 430072 China
| | - Zhen Li
- Hubei Key Lab on Organic and Polymeric Opto-Electronic Materials, Department of Chemistry; Wuhan University; Wuhan 430072 China
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17
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Yang Z, Mao Z, Xie Z, Zhang Y, Liu S, Zhao J, Xu J, Chi Z, Aldred MP. Recent advances in organic thermally activated delayed fluorescence materials. Chem Soc Rev 2017; 46:915-1016. [DOI: 10.1039/c6cs00368k] [Citation(s) in RCA: 1413] [Impact Index Per Article: 201.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Thermally activated delayed fluorescence: harvesting dark triplet excitons to generate bright emissive singlet excitons.
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Affiliation(s)
- Zhiyong Yang
- PCFM Lab
- GD HPPC Lab
- Guangdong Engineering Technology Research Center for High-performance Organic and Polymer Photoelectric Functional Films
- State Key Laboratory of Optoelectronic Material and Technologies
- School of Chemistry
| | - Zhu Mao
- PCFM Lab
- GD HPPC Lab
- Guangdong Engineering Technology Research Center for High-performance Organic and Polymer Photoelectric Functional Films
- State Key Laboratory of Optoelectronic Material and Technologies
- School of Chemistry
| | - Zongliang Xie
- PCFM Lab
- GD HPPC Lab
- Guangdong Engineering Technology Research Center for High-performance Organic and Polymer Photoelectric Functional Films
- State Key Laboratory of Optoelectronic Material and Technologies
- School of Chemistry
| | - Yi Zhang
- PCFM Lab
- GD HPPC Lab
- Guangdong Engineering Technology Research Center for High-performance Organic and Polymer Photoelectric Functional Films
- State Key Laboratory of Optoelectronic Material and Technologies
- School of Chemistry
| | - Siwei Liu
- PCFM Lab
- GD HPPC Lab
- Guangdong Engineering Technology Research Center for High-performance Organic and Polymer Photoelectric Functional Films
- State Key Laboratory of Optoelectronic Material and Technologies
- School of Chemistry
| | - Juan Zhao
- PCFM Lab
- GD HPPC Lab
- Guangdong Engineering Technology Research Center for High-performance Organic and Polymer Photoelectric Functional Films
- State Key Laboratory of Optoelectronic Material and Technologies
- School of Chemistry
| | - Jiarui Xu
- PCFM Lab
- GD HPPC Lab
- Guangdong Engineering Technology Research Center for High-performance Organic and Polymer Photoelectric Functional Films
- State Key Laboratory of Optoelectronic Material and Technologies
- School of Chemistry
| | - Zhenguo Chi
- PCFM Lab
- GD HPPC Lab
- Guangdong Engineering Technology Research Center for High-performance Organic and Polymer Photoelectric Functional Films
- State Key Laboratory of Optoelectronic Material and Technologies
- School of Chemistry
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18
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Ward JS, Nobuyasu RS, Batsanov AS, Data P, Monkman AP, Dias FB, Bryce MR. The interplay of thermally activated delayed fluorescence (TADF) and room temperature organic phosphorescence in sterically-constrained donor–acceptor charge-transfer molecules. Chem Commun (Camb) 2016; 52:2612-5. [DOI: 10.1039/c5cc09645f] [Citation(s) in RCA: 184] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Molecular engineering of phenothiazine–dibenzothiophene-S,S-dioxide molecules is reported.
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19
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Yuan D, Niu L, Chen Q, Jia W, Chen P, Xiong Z. The triplet-charge annihilation in copolymer-based organic light emitting diodes: through the “Scattering Channel” or the “Dissociation Channel”? Phys Chem Chem Phys 2015; 17:27609-14. [DOI: 10.1039/c5cp05016b] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Organic magneto-current of OLEDs reveals that 3LE and 3CT are participants in the “Scattering Channel” and the “Dissociation Channel” of triplet-charge annihilation, respectively.
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Affiliation(s)
- De Yuan
- School of Physical Science and Technology
- MOE Key Laboratory on Luminescence and Real-Time Analysis
- Southwest University
- Chongqing 400715
- P. R. China
| | - Lianbin Niu
- College of Physics and Electronic Engineering
- Chongqing Normal University
- Chongqing 400047
- P. R. China
| | - Qiusong Chen
- School of Physical Science and Technology
- MOE Key Laboratory on Luminescence and Real-Time Analysis
- Southwest University
- Chongqing 400715
- P. R. China
| | - Weiyao Jia
- School of Physical Science and Technology
- MOE Key Laboratory on Luminescence and Real-Time Analysis
- Southwest University
- Chongqing 400715
- P. R. China
| | - Ping Chen
- School of Physical Science and Technology
- MOE Key Laboratory on Luminescence and Real-Time Analysis
- Southwest University
- Chongqing 400715
- P. R. China
| | - Zuhong Xiong
- School of Physical Science and Technology
- MOE Key Laboratory on Luminescence and Real-Time Analysis
- Southwest University
- Chongqing 400715
- P. R. China
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