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Wang W, Bian J, Chen K, Li C, Long Y, Huang H, Jiang L, Zhao J, Liu S, Chi Z, Xu J, Zhang Y. Achieving Record External Quantum Efficiency of 11.5 % in Solution-Processable Deep-Blue Organic Light-Emitting Diodes Utilizing Hot Exciton Mechanism. Angew Chem Int Ed Engl 2024; 63:e202318782. [PMID: 38354089 DOI: 10.1002/anie.202318782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 02/07/2024] [Accepted: 02/09/2024] [Indexed: 02/16/2024]
Abstract
High performance solution-processable deep-blue emitters with a Commission International de l'Eclairage (CIE) coordinate of CIEy≤0.08 are highly desired in ultrahigh-definition display. Although, deep-blue materials with hybridized local and charge-transfer (HLCT) excited-state feature are promising candidates, their rigidity and planar molecular structures limit their application in solution-processing technique. Herein, four novel deep-blue solution-processable HLCT emitters were first proposed by attaching rigid imide aliphatic rings as functional units onto the HLCT emitting core. The functional units not only improve solubility, enhance thermal properties and morphological stability of the emitting core, but also promote photoluminescence efficiency, balance charge carrier transport, and inhibit aggregation-caused quenching effect due to the weak electron-withdrawing property as well as steric hindrance. The corresponding solution-processable organic light-emitting diodes (OLEDs) substantiate an unprecedented maximum external quantum efficiency (EQEmax) of 11.5 % with an emission peak at 456 nm and excellent colour purity (full width at half maximum=56 nm and CIEy=0.09). These efficiencies represent the state-of-the-art device performance among the solution-processable blue OLEDs based on the "hot exciton" mechanism. This simple strategy opens up a new avenue for designing highly efficient solution-processable deep-blue organic luminescent materials.
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Affiliation(s)
- Wenhui Wang
- PCFM Lab, Guangdong Engineering Technology Research Centre for High-performance Organic and Polymer Photoelectric Functional Films, GBRCE for Functional Molecular Engineering, GD HPPC Lab, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry, IGCME, Sun Yat-sen University, Guangzhou, 510275, P. R. China
| | - Jinkun Bian
- PCFM Lab, Guangdong Engineering Technology Research Centre for High-performance Organic and Polymer Photoelectric Functional Films, GBRCE for Functional Molecular Engineering, GD HPPC Lab, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry, IGCME, Sun Yat-sen University, Guangzhou, 510275, P. R. China
| | - Kaijin Chen
- PCFM Lab, Guangdong Engineering Technology Research Centre for High-performance Organic and Polymer Photoelectric Functional Films, GBRCE for Functional Molecular Engineering, GD HPPC Lab, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry, IGCME, Sun Yat-sen University, Guangzhou, 510275, P. R. China
| | - Chuying Li
- PCFM Lab, Guangdong Engineering Technology Research Centre for High-performance Organic and Polymer Photoelectric Functional Films, GBRCE for Functional Molecular Engineering, GD HPPC Lab, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry, IGCME, Sun Yat-sen University, Guangzhou, 510275, P. R. China
| | - Yubo Long
- PCFM Lab, Guangdong Engineering Technology Research Centre for High-performance Organic and Polymer Photoelectric Functional Films, GBRCE for Functional Molecular Engineering, GD HPPC Lab, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry, IGCME, Sun Yat-sen University, Guangzhou, 510275, P. R. China
| | - Haitao Huang
- PCFM Lab, Guangdong Engineering Technology Research Centre for High-performance Organic and Polymer Photoelectric Functional Films, GBRCE for Functional Molecular Engineering, GD HPPC Lab, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry, IGCME, Sun Yat-sen University, Guangzhou, 510275, P. R. China
| | - Long Jiang
- Instrumental Analysis & Research Center, Sun Yat-sen University, Guangzhou, 510275, P. R. China
| | - Juan Zhao
- PCFM Lab, State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou, 510275, P. R. China
| | - Siwei Liu
- PCFM Lab, Guangdong Engineering Technology Research Centre for High-performance Organic and Polymer Photoelectric Functional Films, GBRCE for Functional Molecular Engineering, GD HPPC Lab, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry, IGCME, Sun Yat-sen University, Guangzhou, 510275, P. R. China
| | - Zhenguo Chi
- PCFM Lab, Guangdong Engineering Technology Research Centre for High-performance Organic and Polymer Photoelectric Functional Films, GBRCE for Functional Molecular Engineering, GD HPPC Lab, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry, IGCME, Sun Yat-sen University, Guangzhou, 510275, P. R. China
| | - Jiarui Xu
- PCFM Lab, Guangdong Engineering Technology Research Centre for High-performance Organic and Polymer Photoelectric Functional Films, GBRCE for Functional Molecular Engineering, GD HPPC Lab, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry, IGCME, Sun Yat-sen University, Guangzhou, 510275, P. R. China
| | - Yi Zhang
- PCFM Lab, Guangdong Engineering Technology Research Centre for High-performance Organic and Polymer Photoelectric Functional Films, GBRCE for Functional Molecular Engineering, GD HPPC Lab, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry, IGCME, Sun Yat-sen University, Guangzhou, 510275, P. R. China
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Zhao W, Tan K, Guo W, Guo C, Li M, Chen C. Acceptor Copolymerized Axially Chiral Conjugated Polymers with TADF Properties for Efficient Circularly Polarized Electroluminescence. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2309031. [PMID: 38553794 PMCID: PMC11186117 DOI: 10.1002/advs.202309031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 12/29/2023] [Indexed: 06/20/2024]
Abstract
Chiral conjugated polymer has promoted the development of the efficient circularly polarized electroluminescence (CPEL) device, nevertheless, it remains a challenge to develop chiral polymers with high electroluminescence performance. Herein, by the acceptor copolymerization of axially chiral biphenyl emitting skeleton and benzophenone, a pair of axially chiral conjugated polymers namely R-PAC and S-PAC are synthesized. The target polymers exhibit obvious thermally activated delayed fluorescence (TADF) activities with high photoluminescence quantum yields of 81%. Moreover, the chiral polymers display significant circularly polarized luminescence features, with luminescence dissymmetry factor (|glum|) of nearly 3 × 10-3. By using the chiral polymers as emitters, the corresponding circularly polarized organic light-emitting diodes (CP-OLEDs) exhibit efficient CPEL signals with electroluminescence dissymmetry factor |gEL| of 3.4 × 10-3 and high maximum external quantum efficiency (EQEmax) of 17.8%. Notably, considering both EQEmax and |gEL| comprehensively, the device performance of R-PAC and S-PAC is the best among all the reported CP-OLEDs with chiral conjugated polymers as emitters. This work provides a facile approach to constructing chiral conjugated TADF polymers and discloses the potential of axially chiral conjugated luminescent skeletons in architecting high-performance CP-OLEDs.
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Affiliation(s)
- Wen‐Long Zhao
- Beijing National Laboratory for Molecular SciencesCAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing100190China
- School of Chemical SciencesUniversity of Chinese Academy of SciencesBeijing100049China
| | - Ke‐Ke Tan
- Beijing National Laboratory for Molecular SciencesCAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing100190China
- School of Chemical SciencesUniversity of Chinese Academy of SciencesBeijing100049China
| | - Wei‐Chen Guo
- Beijing National Laboratory for Molecular SciencesCAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing100190China
- School of Chemical SciencesUniversity of Chinese Academy of SciencesBeijing100049China
| | - Chen‐Hao Guo
- College of Chemistry and Chemical EngineeringShanxi UniversityTaiyuan030006China
| | - Meng Li
- Beijing National Laboratory for Molecular SciencesCAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing100190China
- School of Chemical SciencesUniversity of Chinese Academy of SciencesBeijing100049China
| | - Chuan‐Feng Chen
- Beijing National Laboratory for Molecular SciencesCAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing100190China
- School of Chemical SciencesUniversity of Chinese Academy of SciencesBeijing100049China
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Su N, Chen B, Ding J. Two Birds with One Stone: Polymerized Thermally Activated Delayed Fluorescence Small Molecules. Chemistry 2024; 30:e202304095. [PMID: 38246880 DOI: 10.1002/chem.202304095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 01/15/2024] [Accepted: 01/18/2024] [Indexed: 01/23/2024]
Abstract
Thermally activated delayed fluorescence (TADF) polymers show a great potential in low-cost, large-area and flexible full-color flat-panel displays. One of the most promising design rules is based on TADF+Linker, where a small molecular TADF unit is bonded to each other by a simple linker. Unlike the expensive vacuum deposition for small molecules, these polymerized TADF small molecules (Poly-TADF-SMs) are capable of cost-effective solution processing. Meanwhile, the good luminescent property of small molecular TADF emitters can be well inherited by Poly-TADF-SMs so as to bridge the efficiency gap between small molecules and polymers. Herein, we will highlight the recent progress of Poly-TADF-SMs, together with emphasis on their molecular design, photophysical and electroluminescence properties.
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Affiliation(s)
- Ning Su
- School of Chemical Science and Technology, Yunnan University, Kunming, 650091, P. R. China
| | - Bitian Chen
- School of Chemical Science and Technology, Yunnan University, Kunming, 650091, P. R. China
- Southwest United Graduate School, Kunming, 650092, P. R. China
| | - Junqiao Ding
- School of Chemical Science and Technology, Yunnan University, Kunming, 650091, P. R. China
- Southwest United Graduate School, Kunming, 650092, P. R. China
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Zhou T, Zhang W, Cao Q, Zhang K, Ban X, Pei M, Wang J. Unveiling the In Situ and Solvent Polymerization Engineering for Highly Efficient and Flexible Thermally Activated Delayed Fluorescence Organic Light-Emitting Diodes. ACS APPLIED MATERIALS & INTERFACES 2023. [PMID: 37197999 DOI: 10.1021/acsami.3c02412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Thermally activated delayed fluorescence (TADF) polymer has great potential for the construction of flexible solution-processed organic light-emitting diodes (OLEDs). However, the relationship between polymerization engineering and device functions has rarely been reported. Here, two novel TADF polymers, P-Ph4CzCN and P-Ph5CzCN, with a small energy gap between the first excited singlet and triplet states (ΔEST; <0.16 eV) were newly developed by both solvent and in situ polymerization of a styrene component. Detailed device performance testing indicates that both polymerization strategies ensure that the TADF polymer achieves comparable high efficiencies in commonly rigid devices, and the maximum external quantum efficiencies (EQEmax) were 11.9%, 14.1%, and 16.2% for blue, green, and white OLEDs, respectively. Although in situ polymerization provides a simplified device fabrication process, which avoids the complicated synthesis and purification of the polymer, the inevitable high-temperature annealing makes it fail in a plastic substrate device. In contrast, P-Ph5CzCN achieved by solvent polymerization enables the successful fabrication of a flexible device on a poly(ethylene terephthalate) (PET) substrate, which was the first reported flexible OLED based on a TADF polymer. This work provides a strong guideline for the simple fabrication of TADF polymer devices and the application of TADF polymer materials in OLED flexible panels and flexible lighting.
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Affiliation(s)
- Tao Zhou
- School of Environmental and Chemical Engineering, Jiangsu Key Laboratory of Function Control Technology for Advanced Materials, Jiangsu Ocean University, Lianyungang, Jiangsu 222005, China
| | - Wenhao Zhang
- School of Environmental and Chemical Engineering, Jiangsu Key Laboratory of Function Control Technology for Advanced Materials, Jiangsu Ocean University, Lianyungang, Jiangsu 222005, China
| | - Qingpeng Cao
- School of Environmental and Chemical Engineering, Jiangsu Key Laboratory of Function Control Technology for Advanced Materials, Jiangsu Ocean University, Lianyungang, Jiangsu 222005, China
| | - Kaizhi Zhang
- School of Environmental and Chemical Engineering, Jiangsu Key Laboratory of Function Control Technology for Advanced Materials, Jiangsu Ocean University, Lianyungang, Jiangsu 222005, China
| | - Xinxin Ban
- School of Environmental and Chemical Engineering, Jiangsu Key Laboratory of Function Control Technology for Advanced Materials, Jiangsu Ocean University, Lianyungang, Jiangsu 222005, China
| | - Ming Pei
- School of Environmental and Chemical Engineering, Jiangsu Key Laboratory of Function Control Technology for Advanced Materials, Jiangsu Ocean University, Lianyungang, Jiangsu 222005, China
| | - Jiayi Wang
- School of Environmental and Chemical Engineering, Jiangsu Key Laboratory of Function Control Technology for Advanced Materials, Jiangsu Ocean University, Lianyungang, Jiangsu 222005, China
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