Acta Phys. -Chim. Sin. ›› 2015, Vol. 31 ›› Issue (8): 1621-1628.doi: 10.3866/PKU.WHXB201506121

• PHYSICAL CHEMISTRY OF MATERIALS • Previous Articles     Next Articles

ThermallycFluorescence Materials Based on Triphenylamine/Diphenyl Sulfone

Bin. HUANG1,2,Yu. DAI2,Xin-Xin. BAN1,Wei. JIANG1,*(),Zhao-Hang. ZHANG1,Kai-Yong. SUN1,Bao-Ping. LIN1,Yue-Ming. SUN1,*()   

  1. 1 School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, P. R. China
    2 Department of Chemical and Pharmaceutical Engineering, Chengxian College, Southeast University, Nanjing 210088, P. R. China
  • Received:2015-04-07 Published:2015-08-12
  • Contact: Wei. JIANG,Yue-Ming. SUN E-mail:101011462@seu.edu.cn;sun@seu.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(51103023, 21173042);National Key Basic Research Program ofChina (973)(2013CB932900);Natural Science Foundation of Jiangsu Higher Education Institutions, China(14KJB150003)

Abstract:

A series of thermally activated delayed fluorescence (TADF) materials (1-3) based on triphenylamine/diphenyl sulfone were synthesized by Suzuki cross-coupling reactions. The optical, electrochemical, delayed fluorescence, and thermal properties of these materials were characterized by UVVis spectroscopy, time-resolved fluorescence spectroscopic measurements, cyclic voltammetry (CV), theoretical calculations, thermal gravimetric analyses, and differential scanning calorimetry. Materials 1-3 are bipolar compounds based on intramolecular charge transfer (ICT), and they have small energy gaps between the singlet and triplet (ΔEST) of 0.46, 0.39, and 0.29 eV, respectively. The results of fluorescent quantum yields and fluorescent lifetime indicate that these materials can emit delayed fluorescence, and material 3 has the greatest potential as a TADF emitter among materials 1-3. The highest occupied molecular orbital (HOMO) energy levels of materials 1-3 were estimated to be -4.91, -4.89, and -4.89 eV, respectively. From the HOMO energy levels and the optical bandgap (Eg) values, the lowest unoccupied molecular orbital (LUMO) energy levels were estimated to be -1.74, -1.89, and -1.94 eV for materials 1-3, respectively. Thermal gravimetric analysis results reveal that materials 1-3 have high thermal decomposition temperatures (Td), corresponding to 5% weight loss at 436, 387, and 310 ℃, respectively.

Key words: Triphenylamine, Diphenyl sulfone, Bipolar, Intramolecular charge transfer, Energy gap between singlet and triplet, Thermally activated delayed fluorescence

MSC2000: 

  • O644