Chem. J. Chinese Universities ›› 2022, Vol. 43 ›› Issue (11): 20220371.doi: 10.7503/cjcu20220371

• Organic Chemistry • Previous Articles     Next Articles

Methyl-modified Carbazole/Diphenyl Sulfone-based AIE-TADF Blue Emitter and Its OLEDs

WU Zexin1, ZHU Yuanjie1, WANG Hongzhong1, WANG Junan2, HE Ying1()   

  1. 1.Department of Polymer Materials,School of Materials Science and Engineering,Shanghai University,Shanghai 200444,China
    2.Institute of Materials,School of Materials Science and Engineering,Shanghai University,Shanghai 200072,China
  • Received:2022-05-24 Online:2022-11-10 Published:2022-06-14
  • Contact: HE Ying E-mail:yinghe@staff.shu.edu.cn
  • Supported by:
    the Research Projects of Ministry of Education of China(18JDGC025)

Abstract:

A pure organic carbazole/diphenyl sulfone derivative with D-A-D structure, 9,9'-[sulfonylbis(3,1-phenylene)]bis(1,3,6,8-tetramethyl-9H-carbazole)(TMe-mSOCz), was constructed using tetramethyl carbazole as electron donor(D) and diphenyl sulfone as electron acceptor(A). The photophysical properties of the synthesized materials showed that TMe-mSOCz exhibited obvious aggregation-induced emission(AIE) and thermally activated delayed fluorescence(TADF), with delayed lifetime and delayed fluorescence accounting for 2.26 μs and 47.7%, respectively, and good thermal and electrochemical stabilities. The organic light emitting diodes(OLEDs) fabricated based on TMe-mSOCz as the non-doped light-emitting layer exhibits a turn-on voltage(Von) of 3.5 V, the maximum external quantum efficiency of 5.63%, and the International Commission on Illumination(CIE) coordinates of (0.18, 0.26). At 1000 cd/m2 brightness, the non-doped OLED device possesses a very low(7.1%) efficiency roll-off, good color stability, and a narrow full width at half maxima(FWHM) of 72 nm. The research results showed that the introduction of methyl modification between the receptors of traditional TADF molecules was beneficial to the development of D-A-D type TADF molecules with AIE characteristics and higher efficiency, which supplied a new route to OLED emitter fabrication based on AIE-TADF molecules.

Key words: Thermally activated delayed fluorescence, Aggregation-induced emission, Carbazolyl diphenyl sulfone derivative, Organic light emitting diode, Non-doped device

CLC Number: 

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