Exceptionally efficient deep blue anthracene-based luminogens: design, synthesis, photophysical, and electroluminescent mechanisms

作者：Guo, Runda; Liu, Wei; Ying, Shian; Xu, Yuwei; Wen, Yating; Wang, Yaxiong; Hu, Dehua; Qiao, Xianfeng; Yang, Bing; Ma, Dongge^*; Wang, Lei^*

来源：Science Bulletin, 2021, 66(20): 2090-2098.

DOI：10.1016/j.scib.2021.06.018

• Anthracene derivative
• Deep blue luminogen
• Hot excitons
• Triplet-triplet annihilation up-conversion
• Non-doped device

Achieving high-efficiency deep blue emitter with CIEy < 0.06 (CIE, Commission Internationale de L'Eclairage) and external quantum efficiency (EQE) >10% has been a long-standing challenge for traditional fluorescent materials in organic light-emitting diodes (OLEDs). Here, we report the rational design and synthesis of two new deep blue luminogens: 4-(10-(4'-(9H-carbazol-9-yl)-2,5-dimethyl-[1,1'-biphe nyl]-4-yl)anthracen-9-yl)benzonitrile (2M-ph-pCzAnBzt) and 4-(10-(4-(9H-carbazol-9-yl)-2,5-dimethyl phenyl)anthracen-9-yl)benzonitrile (2M-pCzAnBzt). In particular, 2M-ph-pCzAnBzt produces saturated deep blue emissions in a non-doped electroluminescent device with an exceptionally high EQE of 10.44% and CIEx,y (0.151, 0.057). The unprecedented electroluminescent efficiency is attributed to the combined effects of higher-order reversed intersystem crossing and triplet-triplet up-conversion, which are supported by analysis of theoretical calculation, triplet sensitization experiments, as well as nanosecond transient absorption spectroscopy. This research offers a new approach to resolve the shortage of high efficiency deep blue fluorescent emitters.

• 单位
  华中科技大学; 吉林大学