Handbook of Aggregation-Induced Emission, Volume 3

Increasing the efficiency of OLED devices is a complex and integrated challenge in the long term. As for the EMLs, they might have multiple photophysical mechanisms coexisting in the emitters both at the molecular levels and in the aggregated state, therefore the strategic design for the emitters was highly required. Apart from the influence of emitters, many other factors also play significant roles in determining the efficiency of OLED devices such as processing methods, doping, and lighting‐extraction. When it comes to the application of emitters from the laboratory to commercial, these factors, including cost, stability, and lifetime of the device cannot be ignored. From these points, AIE emitters have already been applied in nondoped OLEDs with evident advantages of high efficiency, low cost, and high stability. In spite of these achievement, there is still enough room for developing AIE emitters in OLEDs, such as improving the efficiency of OLEDs or designing novel AIE emitters with other high EUE mechanism of triplet–triplet annihilation (TTA) [130, 131], triplet exciton‐polaron annihilation (TPA) [33], or singlet fission [132]. Finally, we hope that OLED devices will profit more from AIE emitters both academically and commercially in the future.

This work is financially supported by the National Key R&D Program of China (2016YFB0401000, 2017YFE0106000), National Natural Science Foundation of China (21805296, 21876158, 51773212, 21574144 and 21674123), Zhejiang Provincial Natural Science Foundation of China (LR16b040002), Natural Science Foundation of Ningbo City (2018A610134), Ningbo Municipal Science and Technology Innovative Research Team (2015B11002 and 2016b10005), CAS Key Project of Frontier Science Research (QYZDB‐SSW‐SYS030), CAS Key Project of International Cooperation (174433KYSB20160065), and Zhejiang Provincial Natural Science Foundation of China (Grant No. LY20B040002).

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