TY - JOUR
T1 - Intramolecular-Locked High Efficiency Ultrapure Violet-Blue (CIE-y <0.046) Thermally Activated Delayed Fluorescence Emitters Exhibiting Amplified Spontaneous Emission
AU - Khan, Aziz
AU - Tang, Xun
AU - Zhong, Cheng
AU - Wang, Qiang
AU - Yang, Sheng Yi
AU - Kong, Fan Cheng
AU - Yuan, Shuai
AU - Sandanayaka, Atula S.D.
AU - Adachi, Chihaya
AU - Jiang, Zuo Quan
AU - Liao, Liang Sheng
N1 - Funding Information:
A.K. and X.T. contributed equally to the work. The authors acknowledge financial support from the National Natural Science Foundation of China (Nos. 61961160731, 51773141, 51873160, and 51873139) and the Natural Science Foundation of Jiangsu Province of China (BK20181442). This project is also funded by the Collaborative Innovation Center of Suzhou Nano Science & Technology, the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD), and the 111 Project of The State Administration of Foreign Experts Affairs of China. This work was also financially supported by JST ERATO (grant no. JPMJER1305) and Kyushu Organic Laser (KOALA) Tech. Inc.
Publisher Copyright:
© 2021 Wiley-VCH GmbH
PY - 2021/4/8
Y1 - 2021/4/8
N2 - Rational manipulation of frontier orbital distribution and singlet-triplet splitting is crucial to exploit the luminescent properties of organic molecules. To realize ultra-blue luminescence, both blue-shifted wavelength peak (λpeak) and narrow full-width at half-maximum (FWHM) are required. Herein, a new thermally activated delayed fluorescence (TADF) skeleton by inserting the diphenyl methylene intramolecular-lock to adjust the torsion angles and restrict the intramolecular relaxation is developed. Two rigid emitters, incorporating phenoxazine (PXZN-B) and acridine (DMACN-B) as donors and mesitylboron as an acceptor, exhibit narrow FWHMs (<50 nm) with deep-blue (0.133, 0.147) and violet-blue emission (0.151, 0.045), respectively. In particular, the Commission Internationale de l'Eclairage (CIE) coordinates of a DMACN-B-based device closely approach the Rec.2020 standard (0.131, 0.046). Moreover, both of the organic light-emitting diodes (OLEDs) based on PXZN-B and DMACN-B show TADF character, with high external quantum efficiencies (EQEs) exceeding 10%. Furthermore, owing to the large orbital overlap, these TADF emitters own a fast S1–S0 transition rate exceeding 108 s–1, thereby exhibiting marked amplified spontaneous emission (ASE) with low thresholds. Therefore, the intramolecular-lock strategy provides not only innovation for realizing high-efficiency deep-blue TADF emission with high color purity but also an avenue for a TADF-based ASE and lasing application.
AB - Rational manipulation of frontier orbital distribution and singlet-triplet splitting is crucial to exploit the luminescent properties of organic molecules. To realize ultra-blue luminescence, both blue-shifted wavelength peak (λpeak) and narrow full-width at half-maximum (FWHM) are required. Herein, a new thermally activated delayed fluorescence (TADF) skeleton by inserting the diphenyl methylene intramolecular-lock to adjust the torsion angles and restrict the intramolecular relaxation is developed. Two rigid emitters, incorporating phenoxazine (PXZN-B) and acridine (DMACN-B) as donors and mesitylboron as an acceptor, exhibit narrow FWHMs (<50 nm) with deep-blue (0.133, 0.147) and violet-blue emission (0.151, 0.045), respectively. In particular, the Commission Internationale de l'Eclairage (CIE) coordinates of a DMACN-B-based device closely approach the Rec.2020 standard (0.131, 0.046). Moreover, both of the organic light-emitting diodes (OLEDs) based on PXZN-B and DMACN-B show TADF character, with high external quantum efficiencies (EQEs) exceeding 10%. Furthermore, owing to the large orbital overlap, these TADF emitters own a fast S1–S0 transition rate exceeding 108 s–1, thereby exhibiting marked amplified spontaneous emission (ASE) with low thresholds. Therefore, the intramolecular-lock strategy provides not only innovation for realizing high-efficiency deep-blue TADF emission with high color purity but also an avenue for a TADF-based ASE and lasing application.
UR - http://www.scopus.com/inward/record.url?scp=85100486431&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85100486431&partnerID=8YFLogxK
U2 - 10.1002/adfm.202009488
DO - 10.1002/adfm.202009488
M3 - Article
AN - SCOPUS:85100486431
VL - 31
JO - Advanced Functional Materials
JF - Advanced Functional Materials
SN - 1616-301X
IS - 15
M1 - 2009488
ER -