|
|
|
|
|
|
Research Progress on Acceptor Groups of Thermally Activated Delayed Fluorescent Molecules |
SUN Jianan,XU Hui
|
Key Laboratory of Functional Inorganic Material Chemistry (Chinese Ministry of Education),School of Chemistry and Material Science,Heilongjiang University,Harbin 150080,China |
|
|
Abstract In recent years,thermally activated delayed fluorescence (TADF) materials and their electroluminescent devices are developed rapidly. TADF molecules should have small singlet-triplet energy gaps, therefore can facilitate the triplet exciton upconverted to singlet exciton via reverse intersystem crossing (RISC) for radiation. Compared to traditional fluorescence and phosphorescence emitters, besides 100% theoretical internal quantum efficiency and electrogenerated exciton utilization ratio, TADF materials have higher luminescent efficiencies based on pure organic donor-acceptor systems with the features of simple structures and large group library, which attract the extensive attentions. In TADF molecules, acceptors with strong electron-withdrawing ability can effectively facilitate the frontier molecular orbital separation, reduce singlet-triplet energy gaps, improve RISC rate, and simultaneously suppress intermolecular interactions and modify carrier injection and transportation through adjusting molecular configurations. However, in contrast to donor units, the acceptor groups are diverse and completely different regarding to functions, which influences the rational acceptor selection for optoelectronicoptimization. In recent years, the construction of thermally activated delayed fluorescent materials has focused more on the choice of acceptor groups and has achieved remarkable results. Common acceptor groups are phosphine oxide, cyano, triazine, carbonyl, and so on. Intensive research on acceptors groups is critical for regulating intramolecular electronic effects and intermolecular interactions. This review paper summarizes the main acceptor groups used in recently reported TADF molecules and discusses the relationships between acceptor structure and optoelectronic performance, which would be helpful for the subsequent researches on efficient TADF molecular development.
|
Published: 15 January 2020
|
|
Fund:This work was supported by the Chang Jiang Scholars Program (Q2016208), The National Natural Science Foundation of China (51873056, 21672056, 61605042, 21602048), the Postdoc Innovative Talent Support Program of China (BX20180092), The Postdoctoral Science Foundation of China (2018M640313), The Postdoctoral Fund of Heilongjiang (LBN-Z18233) and Fundamental Research Project of Basic Scientific Research Business Expenses of Heilongjiang Provincial Universities (RCCXYJ201804). |
About author:: Jianan Sun graduated from Heilongjiang University in June 2017 with a Bachelor of Science degree. She is currently studying for master degree of organic chemistry at Heilongjiang University under the supervision of prof. Hui Xu. Her research direction is the synthesis and characterization of thermally activated delayed fluorescent materials based on aromatic phosphine oxide acceptors. Hui Xu is deputy director of the Key Laboratory of Functional Inorganic Material Chemistry. He joined Heilongjiang University in 2006 and promoted full professor in 2011. He was elected in the Young Changjiang Scholarship by Chinese Ministry of Education and awarded the Humboldt Fellowship for Experienced Researcher in 2017. He has published 93 peer-reviewed SCI papers in Sci. Adv., Chem, J. Am. Chem. Soc., Angew. Chem. Int. Ed., Adv. Mater. and so on, with citations over 3000, and awarded the first class of Heilongjiang province science and technology award. His current research focuses on phosphine-based host and guest materials, as well as the low-voltage-driven full-color OLEDs and dual emissive materials for high-efficiency devices. |
|
|
1 Tang C W, VanSlyke S A, Applied Physics Letters, 1987, 51, 913. 2 Muller C D, Falcou A, Reckefuss N, et al. Nature, 2003, 421, 829. 3 Baldo M A, O'Brien D F, You Y, et al. Nature, 1998, 395, 151. 4 Endo A, Ogasawara M, Takahashi A, et al. Advanced Materials, 2009, 21, 4802. 5 Uoyama H, Goushi K, Shizu K, et al. Nature, 2012, 492, 234. 6 Tao Y, Yuan K, Chen T, et al. Advanced Materials, 2014, 26, 7931. 7 Yang Z, Mao Z, Xie Z, et al. Chemical Society Reviews, 2017, 46, 915. 8 Cai X, Su S J. Advanced Functional Materials, 2018, 28, 1802558. 9 Wolf M W, Legg K D, Brown R E, et al. Journal of the American Chemical Society, 1975, 97, 4490. 10 Jiang K, Wang Y, Cai C, et al. Chemistry of Materials, 2017, 29, 4866. 11 Lee S Y, Adachi C, Yasuda T. Advanced Materials, 2016, 28, 4626. 12 Duan C, Li J, Han C, et al. Chemistry of Materials 2016, 28, 5667. 13 Liang Q, Han C, Duan C, et al. Advanced Optical Materials, 2018, 6, 1800020. 14 Li C, Duan C, Han C, et al. Advanced Materials, 2018, 30, 1804228. 15 Gao F, Du R, Han C, et al. Chemical Science, 2019, 10, 5556. 16 Sun J W, Lee J H, Moon C K, et al. Advanced Materials, 2014, 26, 5684. 17 Cho Y J, Chin B D, Jeon S K, et al. Advanced Functional Materials, 2015, 25, 6786. 18 Byeon S Y, Kim J H, Lee J Y. ACS Applied Materials & Interfaces, 2017, 9, 13339. 19 Park I S, Lee S Y, Adachi C, et al. Advanced Functional Materials, 2016, 26, 1813. 20 Cheng Z, Li Z, Xu Y, et al. ACS Applied Materials & Interfaces, 2019, 11, 28096. 21 Saigo M, Miyata K, Tanaka S, et al. The Journal of Physical Chemistry Letters, 2019, 10, 2475. 22 Lee H L, Lee K H, Lee J Y, et al. Journal of Materials Chemistry C, 2019, 7, 6465. 23 Jayakumar J, Wu T L, Huang M J, et al. ACS Applied Materials & Interfaces, 2019, 11, 21042. 24 Vigante B, Leitonas K, Volyniuk D, et al. Chemistry-A European Journal, 2019, 25, 3325. 25 Sun J W, Baek J Y, Kim K H, et al. Chemistry of Materials, 2015, 27, 6675. 26 Lee D R, Kim M, Jeon S K, et al. Advanced Materials, 2015, 27, 5861. 27 Kim M, Choi J M, Lee J Y. Chemical Communications, 2016, 52, 10032. 28 Kang Y J, Lee J Y. Dyes and Pigments, 2017, 138, 176. 29 Cui L S, Nomura H, Geng Y, et al. Angewandte Chemie International Edition, 2017, 56, 1571. 30 Woo S J, Kim Y, Kim M J, et al. Chemistry of Materials, 2018, 30(3), 857. 31 Woo S J, Kim Y, Kwon S K, et al. ACS Applied Materials & Interfaces, 2019, 11, 7199. 32 Kang Y J, Yun J H, Han S H, et al. Journal of Materials Chemistry C, 2019, 7, 4573. 33 Yu J G, Han S H, Lee H L, et al. Journal of Materials Chemistry C, 2019, 7, 2919. 34 Li W, Li B, Cai X, et al. Angewandte Chemie International Edition, 2019, 58, 11301. 35 Braveenth R, Lee H, Kim S, et al. Journal of Materials Chemistry C, 2019, 7, 7672. 36 Wang Q, Zhang Y X, Yuan Y, et al. ACS Applied Materials & Interfaces, 2019, 11, 2197. 37 Cai X, Gao B, Li X L, et al. Advanced Functional Materials, 2016, 26, 8042. 38 Rajamalli P, Senthilkumar N, Huang P Y, et al. Journal of the American Chemical Society, 2017, 139, 10948. 39 Guo J, Li X L, Nie H, et al. Advanced Functional Materials, 2017, 27, 1606458. 40 Liang J, Li C, Zhuang X, et al. Advanced Functional Materials, 2018, 28, 1707002. 41 Cai X, Chen D, Gao K, et al. Advanced Functional Materials, 2018, 28, 1704927. 42 Liu H, Zeng J, Guo J, et al. Angewandte Chemie International Edition, 2018, 57, 9290. 43 Thangaraji V, Rajamalli P, Jayakumar J, et al. ACS Applied Materials & Interfaces, 2019, 11, 17128. |
|
|
|