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11 Jan 02:05

Facile Synthesis of Polycyclic Pentalenes with Enhanced Hückel Antiaromaticity

Facile Synthesis of Polycyclic Pentalenes with Enhanced Hückel Antiaromaticity

Polycyclic pentalenes with phenanthrene-type π extensions were prepared from 1,4-bis(bromoaryl)-1,3-butadiynes by successive transannular cyclizations of the in situ generated tetrakisdehydro[16]annulenes. These polycyclic pentalenes show not only high thermal stability, but also intriguing absorption and redox properties, due to the pronounced Hückel antiaromaticity.

[Communication]
Hiroya Oshima, Aiko Fukazawa, Shigehiro Yamaguchi
Angew. Chem. Int. Ed., January 09, 2017, DOI: 10.1002/anie.201611344. Read article

05 Jan 13:13

Conjugation-Induced Thermally Activated Delayed Fluorescence (TADF): From Conventional Non-TADF Units to TADF-Active Polymers

by Qiang Wei, Paul Kleine, Yevhen Karpov, Xianping Qiu, Hartmut Komber, Karin Sahre, Anton Kiriy, Ramunas Lygaitis, Simone Lenk, Sebastian Reineke, Brigitte Voit

Thermally activated delayed fluorescence (TADF)-type compounds have great potential as emitter molecules in organic light-emitting diodes, allowing for electrofluorescence with 100% internal quantum efficiency. In small molecules, TADF is achieved through the formation of intramolecular charge-transfer states. The only design limitation is the requirement that donor and acceptor entities spatially decouple the highest occupied and lowest unoccupied molecular orbitals, respectively, to minimize exchange splitting. The development of polymeric TADF emitters, on the contrary, has seen comparably small progress and those are typically built up from monomeric units that show promising TADF properties in small molecule studies beforehand. By contrast, herein, a way to achieve TADF properties in cyclic oligomers and polymers composed of non-TADF building blocks is shown. Due to a strongly decreased energy splitting of the polymer with respect to the individual repeating unit between the lowest singlet and triplet excited state (ΔEST) and a sufficiently high radiative decay rate kSr, a highly efficient TADF polymer with up to 71% photoluminescence quantum yield is obtained. For the first time, an encouraging method is provided for producing highly efficient TADF oligomers and polymers from solely non-TADF units via induced conjugation, opening a new design strategy exclusive for polymers.

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A thermally activated delayed fluorescence (TADF) π-conjugated cyclic polymer composed of non-TADF building blocks is developed. Conjugation-induced highest occupied molecular orbital destabilization leads to a decreased singlet–triplet splitting and efficient TADF in the polymer, while the repeating unit itself shows only inefficient phosphorescence. This conjugation-induced TADF concept represents a novel molecular design rule particularly for solution-processable polymeric materials.

29 Dec 08:28

Indolo[3,2-b]indole-based crystalline hole-transporting material for highly efficient perovskite solar cells

Chem. Sci., 2017, 8,734-741
DOI: 10.1039/C6SC02832B, Edge Article
Open Access Open Access
Creative Commons Licence&nbsp This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
Illhun Cho, Nam Joong Jeon, Oh Kyu Kwon, Dong Won Kim, Eui Hyuk Jung, Jun Hong Noh, Jangwon Seo, Sang Il Seok, Soo Young Park
A fluorinated indolo[3,2-b]indole (IDID) derivative is prepared as a crystalline hole transporting material for perovskite solar cells. A fluorinated IDID backbone enables a tight molecular stacking by [small pi]-[small pi] interaction. The device fabricated using IDIDF exhibits a PCE of 19%.
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29 Dec 07:10

One-Step Annulative π-Extension of Alkynes with Dibenzosiloles or Dibenzogermoles by Palladium/o-chloranil Catalysis

One‐Step Annulative π‐Extension of Alkynes with Dibenzosiloles or Dibenzogermoles by Palladium/o‐chloranil Catalysis

Extending circumstances: An efficient one-step annulative π-extension reaction of alkynes provides facile access to diarylphenanthrenes and related nanographene precursors. In the presence of a cationic palladium/o-chloranil catalyst system, a variety of diarylacetylenes are transformed through the use of dibenzosiloles or dibenzogermoles as π-extending agents into 9,10-diarylphenanthrenes with good functional-group tolerance.

[Communication]
Kyohei Ozaki, Keiichiro Murai, Wataru Matsuoka, Katsuaki Kawasumi, Hideto Ito, Kenichiro Itami
Angew. Chem. Int. Ed., December 21, 2016, DOI: 10.1002/anie.201610374. Read article

03 Dec 03:01

Donor-acceptor-acceptor (D-A-A) type 1,8-naphthalimides as non-fullerene small molecule acceptors for bulk heterojunction solar cells

Chem. Sci., 2017, 8,2017-2024
DOI: 10.1039/C6SC04461A, Edge Article
Open Access Open Access
Prabhat Gautam, Rahul Sharma, Rajneesh Misra, M. L. Keshtov, S. A. Kuklin, Ganesh D. Sharma
Donor-acceptor-acceptor (D-A-A) type 1,8-naphthalimide based small molecules SM1 and SM2 functionalized with tetracyanobutadiene (TCBD) and dicyanoquino-dimethane (DCNQ) modules, showing strong absorption in the visible and near-infrared (NIR) region are reported.
The content of this RSS Feed (c) The Royal Society of Chemistry
03 Dec 02:58

High Photovoltage All-Polymer Solar Cells based on a Diketopyrrolopyrrole-Isoindigo Acceptor Polymer

J. Mater. Chem. A, 2016, Accepted Manuscript
DOI: 10.1039/C6TA09379E, Paper
Zhaojun Li, Xiaofeng Xu, Wei Zhang, Zewdneh Genene, Wendimagegn Mammo, Arkady Yartsev, Mats Andersson, Rene A J Janssen, Ergang Wang
In this work, we synthesized and characterized two new n-type polymers PTDPP-PyDPP and PIID-PyDPP. The former polymer is composed of pyridine-flanked diketopyrrolopyrrole (PyDPP) and thiophene-flanked diketopyrrolopyrrole (TDPP). The latter polymer...
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03 Dec 02:57

Control of the molecular geometry and nanoscale morphology in perylene diimide based bulk heterojunctions enables an efficient non-fullerene organic solar cell

J. Mater. Chem. A, 2017, 5,210-220
DOI: 10.1039/C6TA08870H, Paper
R. Singh, J. Lee, M. Kim, P. E. Keivanidis, K. Cho
In this contribution, we studied the effects of 3D molecular geometry in non-fullerene solar cells based on perylene diimide small molecules.
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03 Dec 02:54

Comparative Study on the Photovoltaic Characteristics of A-D-A and D-A-D Molecules Based on Zn-Porphyrin; a D-A-D Molecule with Over 8.0% Efficiency

J. Mater. Chem. A, 2016, Accepted Manuscript
DOI: 10.1039/C6TA09408B, Paper
Virginia Virginia Cuesta, Maida Vartanian, Pilar de la Cruz, Rahui Singhai, Ganesh D Sharma, Fernando Langa
The synthesis of two symmetrical molecules with A-D-A (1) and D-A-D (2) structures is reported. The compounds have Zn-porphyrin as the donor component and 3,6-di(thiophen-2-yl)pyrrolo[3,4-c]pyrrole-1,4-dione (DT-DPP) as the acceptor unit...
The content of this RSS Feed (c) The Royal Society of Chemistry
03 Dec 02:52

Structure-simplified and highly efficient deep blue organic light-emitting diodes with reduced efficiency roll-off at extremely high luminance

Chem. Commun., 2016, 52,14454-14457
DOI: 10.1039/C6CC08501F, Communication
Xiang-Long Li, Ming Liu, Yunchuan Li, Xinyi Cai, Dongcheng Chen, Kunkun Liu, Yong Cao, Shi-Jian Su
Deep blue non-doped multilayer OLEDs with EQEs exceeding 5.10% and single layer devices excluding any carrier transporting materials with an EQE of 4.22% were obtained at an extremely high luminance of 10 000 cd m-2.
The content of this RSS Feed (c) The Royal Society of Chemistry
03 Dec 02:44

A Thieno[3,4-b]thiophene-Based Non-fullerene Electron Acceptor for High-Performance Bulk-Heterojunction Organic Solar Cells

by Feng Liu, Zichun Zhou, Cheng Zhang, Thomas Vergote, Haijun Fan, Feng Liu and Xiaozhang Zhu

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Journal of the American Chemical Society
DOI: 10.1021/jacs.6b08523
20 Nov 13:04

A diketopyrrolopyrrole-based low bandgap polymer with enhanced photovoltaic performances through backbone twisting

J. Mater. Chem. A, 2016, 4,18174-18180
DOI: 10.1039/C6TA08130D, Paper
Shuguang Wen, Weichao Chen, Meijie Fan, Linrui Duan, Meng Qiu, Mingliang Sun, Liangliang Han, Renqiang Yang
Two DPP-BDT alternating conjugated polymers with a twisted backbone were synthesized and a high efficiency of 8.11% was obtained in a photovoltaic device.
The content of this RSS Feed (c) The Royal Society of Chemistry
20 Nov 13:03

Synergistic effect of fluorination and regio-regularity on the long-term thermal stability of polymer solar cells

J. Mater. Chem. A, 2016, 4,18598-18606
DOI: 10.1039/C6TA06610K, Paper
Zidong Li, Tong Zhang, Yue Xin, Xiaoli Zhao, Dalei Yang, Fan Wu, Xiaoniu Yang
The synergistic effect of fluorination and regio-regularity is proposed for the first time to realize the long-term thermal stability of polymer solar cells.
The content of this RSS Feed (c) The Royal Society of Chemistry
20 Nov 12:58

Electropolymerized AIE-active polymer film with high quantum efficiency and its application in OLED

by Jinyu Li, Xiao Han, Qing Bai, Tong Shan, Ping Lu, Yuguang Ma

ABSTRACT

A carbazole functionalized electro-active AIE-activity molecule, TPE-DFCz, was designed, synthesized, and well characterized. The clear difference in oxidation potentials between tetraphenylethylene (TPE) unit and carbazole groups was found which guaranteed that polymerization occurred only at the peripheral carbazole groups and the TPE unit remained unchanged. Its luminescent network film was prepared conveniently by electrochemical polymerization (EP). The cross-linked film exhibited green emission with high quantum efficiency of 63%, relatively smooth surface, and good thermal stability. The effect of different scan cycles on the optical property was also investigated. The electroluminescent device using the optimized polymer film as active layer showed a maximum luminance of 3200 cd m−2 and a maximum luminance efficiency of 1.16 cd A−1 with very low roll-off of the efficiency. The AIE-active EP films afford more opportunities to develop polymer films with high quantum efficiency via a simple, effective method and promote the potential applications in display devices. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 707–715

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A new AIE molecule, TPE-DFCz, is obtained and its luminescent network film is prepared conveniently by electrochemical polymerization. The cross-linked film exhibits high quantum efficiency of 63%, relatively smooth surface, and good thermal stability. OLEDs using the polymerized film as the active layer show a maximum luminance of 3200 cd m−2 and a maximum luminance efficiency of 1.16 cd A−1 with very low roll-off of the efficiency.

20 Nov 12:58

A Synergetic Effect of Molecular Weight and Fluorine in All-Polymer Solar Cells with Enhanced Performance

by Shanshan Chen, Yujin An, Gitish K. Dutta, Yiho Kim, Zhi-Guo Zhang, Yongfang Li, Changduk Yang

A synergetic effect of molecular weight (Mn) and fluorine (F) on the performance of all-polymer solar cells (all-PSCs) is comprehensively investigated by tuning the Mn of the acceptor polymer poly((N,N′-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl)-alt-5,5′-(2,2′-bithiophene)) (P(NDI2OD-T2)) and the F content of donor polymer poly(2,3-bis-(3-octyloxyphenyl)quinoxaline-5,8-dyl-alt-thiophene-2,5-diyl). Both Mn and F variations strongly influence the charge transport properties and morphology of the blend films, which have a significant impact on the photovoltaic performance of all-PSCs. In particular, the effectiveness of high Mn in increasing power conversion efficiency (PCE) can be greatly improved by the devices based on optimum F content, reaching a PCE of 7.31% from the best all-PSC combination. These findings enable us to further understand the working principles of all-PSCs with a view on achieving even higher power conversion efficiency in the future.

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To establish a correlation between the effects of molecular weight (Mn) and fluorine (F) on photovoltaic performance, all-polymer solar cells have been comprehensively investigated based on donor polymers of TQ family with various F content and P(NDI2OD-T2) acceptor polymers with various Mn. An efficiency of 7.31% is demonstrated by blending the optimum F content-containing donor with a high Mn acceptor.

20 Nov 12:47

Isoindigo-Based Semiconducting Polymers Using Carbosilane Side Chains for High Performance Stretchable Field-Effect Transistors

by Hung-Chin Wu, Chih-Chien Hung, Chian-Wen Hong, Han-Sheng Sun, Jau-Tzeng Wang, Go Yamashita, Tomoya Higashihara and Wen-Chang Chen

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Macromolecules
DOI: 10.1021/acs.macromol.6b02145
20 Nov 12:45

Side-Chain Isomerization on an n-type Organic Semiconductor ITIC Acceptor Makes 11.77% High Efficiency Polymer Solar Cells

by Yankang Yang, Zhi-Guo Zhang, Haijun Bin, Shanshan Chen, Liang Gao, Lingwei Xue, Changduk Yang and Yongfang Li

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Journal of the American Chemical Society
DOI: 10.1021/jacs.6b09110
27 Oct 05:33

Fullerene-free polymer solar cell based on a polythiophene derivative with an unprecedented energy loss of less than 0.5 eV

J. Mater. Chem. A, 2016, 4,18043-18049
DOI: 10.1039/C6TA07672F, Paper
Hao Zhang, Sunsun Li, Bowei Xu, Huifeng Yao, Bei Yang, Jianhui Hou
A polymer solar cell was fabricated with a high open-circuit voltage of 1.13 V and a low energy loss of 0.46 eV.
The content of this RSS Feed (c) The Royal Society of Chemistry
14 Oct 10:44

Terminal moiety-driven electrical performance of asymmetric small-molecule-based organic solar cells

J. Mater. Chem. A, 2016, 4,15688-15697
DOI: 10.1039/C6TA07450B, Paper
Jianhua Huang, Shanlin Zhang, Bo Jiang, Yuxia Chen, Xinliang Zhang, Zhuxin Fan, Donghong Yu, Zhiyong Lin, Jiannian Yao, Chuanlang Zhan
With respect to the successes from symmetric small molecules, asymmetric ones have recently emerged as an alternative choice.
The content of this RSS Feed (c) The Royal Society of Chemistry
14 Oct 10:18

High efficiency organic photovoltaic devices based on isoindigo conjugated polymers with a thieno[3,2-b]thiophene [small pi]-bridge

J. Mater. Chem. A, 2016, 4,16064-16072
DOI: 10.1039/C6TA07138D, Paper
Lei Zhu, Min Wang, Bowen Li, Chao Jiang, Qifang Li
We introduce a thieno[3,2-b]thiophene [small pi]-bridge into isoindigo and BDT units to construction conjugated polymers and achieve a PCE of 8.05%.
The content of this RSS Feed (c) The Royal Society of Chemistry
17 Sep 23:58

Indolo[3,2-b]indole-based crystalline hole-transporting material for highly efficient perovskite solar cells

Chem. Sci., 2016, Advance Article
DOI: 10.1039/C6SC02832B, Edge Article
Open Access Open Access
Creative Commons Licence&nbsp This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
Illhun Cho, Nam Joong Jeon, Oh Kyu Kwon, Dong Won Kim, Eui Hyuk Jung, Jun Hong Noh, Jangwon Seo, Sang Il Seok, Soo Young Park
A fluorinated indolo[3,2-b]indole (IDID) derivative is prepared as a crystalline hole transporting material for perovskite solar cells. A fluorinated IDID backbone enables a tight molecular stacking by [small pi]-[small pi] interaction. The device fabricated using IDIDF exhibits a PCE of 19%.
To cite this article before page numbers are assigned, use the DOI form of citation above.
The content of this RSS Feed (c) The Royal Society of Chemistry
09 Sep 08:03

High-Performance Field-Effect Transistors Fabricated with Donor–Acceptor Copolymers Containing S···O Conformational Locks Supplied by Diethoxydithiophenethenes

by Weifeng Zhang, Zupan Mao, Jianyao Huang, Dong Gao and Gui Yu

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Macromolecules
DOI: 10.1021/acs.macromol.6b01510
09 Sep 07:57

Effect of Fluorination on Molecular Orientation of Conjugated Polymers in High Performance Field-Effect Transistors

by Andong Zhang, Chengyi Xiao, Yang Wu, Cheng Li, Yunjing Ji, Lin Li, Wenping Hu, Zhaohui Wang, Wei Ma and Weiwei Li

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Macromolecules
DOI: 10.1021/acs.macromol.6b01446
09 Sep 07:21

Energy-Level Modulation of Small-Molecule Electron Acceptors to Achieve over 12% Efficiency in Polymer Solar Cells

by Sunsun Li, Long Ye, Wenchao Zhao, Shaoqing Zhang, Subhrangsu Mukherjee, Harald Ade, Jianhui Hou
Z Xin

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Fine energy-level modulations of small-molecule acceptors (SMAs) are realized via subtle chemical modifications on strong electron-withdrawing end-groups. The two new SMAs (IT-M and IT-DM) end-capped by methyl-modified dicycanovinylindan-1-one exhibit upshifted lowest unoccupied molecular orbital (LUMO) levels, and hence higher open-circuit voltages can be observed in the corresponding devices. Finally, a top power conversion efficiency of 12.05% is achieved.

29 Aug 10:58

Controlling Energy Levels and Blend Morphology for All-Polymer Solar Cells via Fluorination of a Naphthalene Diimide-Based Copolymer Acceptor

by Mohammad Afsar Uddin, Youngkwon Kim, Robert Younts, Wonho Lee, Bhoj Gautam, Joonhyeong Choi, Cheng Wang, Kenan Gundogdu, Bumjoon J. Kim and Han Young Woo

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Macromolecules
DOI: 10.1021/acs.macromol.6b01414
29 Aug 10:55

Effect of Alkyl Side Chains of Conjugated Polymer Donors on the Device Performance of Non-Fullerene Solar Cells

by Dongdong Xia, Yang Wu, Qiang Wang, Andong Zhang, Cheng Li, Yuze Lin, Fallon J. M. Colberts, Jacobus J. van Franeker, René A. J. Janssen, Xiaowei Zhan, Wenping Hu, Zheng Tang, Wei Ma and Weiwei Li

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Macromolecules
DOI: 10.1021/acs.macromol.6b01326
22 Aug 08:09

High Performance All-Polymer Solar Cells by Synergistic Effects of Fine-Tuned Crystallinity and Solvent Annealing

by Zhaojun Li, Xiaofeng Xu, Wei Zhang, Xiangyi Meng, Wei Ma, Arkady Yartsev, Olle Inganäs, Mats. R. Andersson, René A. J. Janssen and Ergang Wang
Z Xin

~

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Journal of the American Chemical Society
DOI: 10.1021/jacs.6b04822
20 Aug 01:04

Conjugated Random Donor–Acceptor Copolymers of [1]Benzothieno[3,2-b]benzothiophene and Diketopyrrolopyrrole Units for High Performance Polymeric Semiconductor Applications

by Vishnu Sukumaran Nair, Jibin Sun, Penglin Qi, Sifen Yang, Zitong Liu, Deqing Zhang and Ayyappanpillai Ajayaghosh
Z Xin

~

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Macromolecules
DOI: 10.1021/acs.macromol.6b00954
19 Aug 12:53

Organic LEDs: Sky-Blue Organic Light Emitting Diode with ≈37% External Quantum Efficiency Using Thermally Activated Delayed Fluorescence from Spiroacridine-Triazine Hybrid (Adv. Mater. 32/2016)

by Ting-An Lin, Tanmay Chatterjee, Wei-Lung Tsai, Wei-Kai Lee, Meng-Jung Wu, Min Jiao, Kuan-Chung Pan, Chih-Lung Yi, Chin-Lung Chung, Ken-Tsung Wong, Chung-Chih Wu
Z Xin

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Extremely efficient blue organic electroluminescence with external quantum efficiency of 37% with a conventional planar device structure is reported by K.-T. Wong, C.-C. Wu, and co-workers on page 6976. Such a high efficiency is realized by thermally activated delayed fluorescence emitters based on spiroacridine–triazine hybrids, which simultaneously possess nearly 100% photoluminescence quantum yield and strongly horizontally oriented emitting dipoles.

17 Aug 02:24

Design Strategy of Blue and Yellow Thermally Activated Delayed Fluorescence Emitters and Their All-Fluorescence White OLEDs with External Quantum Efficiency beyond 20%

by Yunchuan Li, Xiang-Long Li, Dongjun Chen, Xinyi Cai, Gaozhan Xie, Zuozheng He, Yuan-Chun Wu, Alan Lien, Yong Cao, Shi-Jian Su
Z Xin

~

Two thioxanthone-derived isomeric series of thermally activated delayed fluorescence (TADF) emitters 1,6-2TPA-TX/3,6-2TPA-TX and 1,6-2TPA-TXO/3,6-2TPA-TXO are developed for organic light-emitting diodes (OLEDs). Blue emission devices based on symmetrical 3,6-2TPA-TX with common vertical transition route realize an extremely high external quantum efficiency (EQE) of 23.7%, and an ever highest EQE of 24.3% is achieved for yellow emission devices based on 3,6-2TPA-TXO by solely changing the sulfur atom valence state of the thioxanthone core. In contrast, their corresponding asymmetric isomers are affected by intramolecular energy transfer and more severely by a nonradiative deactivation pathway, to give much low EQE values (<5%). By utilizing 3,6-2TPA-TX as a blue emitter and 3,6-2TPA-TXO as a yellow emitter, an ever highest EQE of 20.4% is achieved for all-fluorescence white OLEDs.

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Two thioxanthone-derived isomeric series of thermally activated delayed fluorescence emitters with the same electron acceptor and electron donor but different donor combining strategy are developed. Highly efficient sky-blue, yellow, and white organic light-emitting diodes are achieved by 3,6-2TPA-TX and 3,6-2TPA-TXO with symmetrical configuration and common vertical transition route.

28 Jul 00:38

Color Tuning of Avobenzone Boron Difluoride as an Emitter to Achieve Full-Color Emission

by Hin-Wai Mo, Youichi Tsuchiya, Yan Geng, Takehiro Sagawa, Chika Kikuchi, Hajime Nakanotani, Fuyuki Ito, Chihaya Adachi
Z Xin

~

Organic light-emitting diodes (OLEDs) displaying a wide range of emission colors with emission peaks from 450 to 665 nm using a single emitting material, avobenzone boron difluoride (AVB-BF2), are reported. Color tuning is achieved by controlling the aggregation of AVB-BF2 and the formation of a “triadic” exciplex of an AVB-BF2 dimer and a host molecule. Various electroluminescent devices containing AVB-BF2 cover the whole visible light spectrum and a white-emitting device with CIE coordinates of (0.35, 0.37) is obtained with a single emitting material in a single emissive layer. Furthermore, an exceptionally high external quantum efficiency of nearly 13% is achieved for a green-emitting OLED because AVB-BF2 exhibits thermally activated delayed fluorescence by forming the exciplex.

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Full-color-tunable OLEDs that can also achieve white emission are demonstrated by using a single emitter and a single emissive layer through a new strategy exploiting both aggregation and exciplex formation. The aggregation formation induces emission color shift from blue to green. Further color shift to red is provided by the aggregation induced exciplex formation through the triadic exciplex formation between aggregated emitter and host molecules.