Speakers

Prof. Dongge Ma received his B. S. degree from Liaoning University in 1989, and M.S. and Ph.D. degree from Jilin University in 1992 and 1995, respectively. From 1995-1998, he worked as a postdoct/associate professor at Changchun Institute of Applied Chemistry, Chinese Academy of Science. During 1998-2001, he became a visiting professor at Universidade Federal do Parana, Brazil, and a senior research fellow at Durham University and St Andrews University, UK. He joined State Key Lab of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Science as a full professor in 2001. Since 2016, he has been a full professor at State Key Laboratory of Luminescence Materials and Devices in South China University of Technology. He was highly cited scientist of Thomson Reuters (Clarivate) from 2014 to 2018. His research interests are on organic optoelectronic devices and physics, including organic light-emitting diodes (OLEDs) and its applications in lighting, organic photodetectors (OPDs), organic spintronics, organic lasers and exciton dynamics and electronic processes in organic semiconductors.

High Efficiency OLEDs Based on AIE Materials/ reference format

Abstract

Aggregation-induced emission (AIE) luminogens (AIEgens) have become an promising electroluminscence material in organic light-emitting diodes (OLEDs) due to the important characteristic of a strong emission with 100% photoluminescence (PL) quantum efficiency in solid film, which has been attributed to the highly twisted conformation and weak intermolecular interaction. In this report, we fabricated high efficiency of over 7% blue OLEDs based on non-doped AIEs as emitter, and further improved it to 10.2% by the design of device structure. More recently, we found that the EL emission of AIE materials exists severe singlet–triplet annihilation (STA), and the STA can be efficiently suppressed by doping a triplet-triplet annihilation up-conversion organic molecule, thus the efficiency of the resulting blue OLEDs was enhanced to 11.8% with CIE coordinates of (0.15, 0.07). The detailed mechanisms were studied by theory calculation, and photophysics and magnetic electroluminescence (MEL) measurements. In addition, we found that AIEs are also excellent host of red, green and yellow phosphors, thus high efficiency phosphorescence OLEDs can be fabricated. On this basis, we have successfully developed white OLEDs based on highly efficient blue AIE molecules. The power efficiency reaches about the maximum value of 100 lm/W and 72.1 lm/W at the luminance of 1000 cd/m2.

Figure 1. Device structure of two AIE materials doped OLEDs (left) and their EQE-luminance characteristics.

References

1. Xu, Z.; Gu, J.; Qiao, X. Qiao,; Qin, A.; Tang, B. Z.; Ma, D. ACS Photonics 2019, 6, 767.
2.  Guo, X.; Yuan, P.; Qiao, X.; Yang, D.; Dai, Y.; Sun, Q.; Qin, A.; Tang, B. Z.; Ma, D. Adv. Funct. Mater. 2020, 30, 908704.
3. Guo, X.; Yuan, P.; Fan, J.; Qiao, X.; Yang, D.; Dai, Y.; Sun, Q.; Qin, A.; Tang, B. Z.; Ma, D. Adv. Mater. 2021, 33, 2006953.
4. Lin, C.; Han, P.; Qu, F.; Xiao, S.; Li, Y.; Xie, D.; Qiao, X.; Yang, D.; Dai, Y.; Sun, Q.; Qin, A.; Tang, B. Z.; Ma, D. Mater. Horizon 2022, : DOI: 10.1039/d2mh00627h.