Narrowband Emission from Organic Fluorescent Emitters with Dominant Low-Frequency Vibronic Coupling

作者：Qiu, Xu; Tian, Guangjun; Lin, Chengwei; Pan, Yuyu; Ye, Xiyun; Wang, Bohan; Ma, Dongge; Hu, Dehua^*; Luo, Yi^*; Ma, Yuguang^*

来源：Advanced Optical Materials, 2021, 9(4): 2001845.

DOI：10.1002/adom.202001845

• dominant low-frequency vibronic coupling
• narrowband emission
• organic fluorescent emitters
• organic light-emitting diodes
• small reorganization energy

Organic fluorescent emitters with narrowband emissions are highly desirable for high-resolution organic light-emitting diode (OLED) display technology. In principle, this can be achieved by specifically controlling the intrinsic structural relaxation and vibronic coupling in the excited state. Here, a design strategy to realize narrowband emission of organic fluorescent emitters is proposed by significantly enhancing the low-frequency vibronic coupling strength (Lambda) while simultaneously reducing the high-frequency. of the commonly involved stretching modes. The quinolino-[3,2,1-de]acridine-5,9-dione (QAO) species is found to be directly associated with this design principle. By introducing single bond-linked peripheral moieties into the QAO core, the constructed QAO derivatives are shown to exhibit better performance, by achieving a full width at halfmaximum of 23 nm/0.13 eV in toluene for the narrowest band as well as 27 nm/0.15 eV in doped devices, with negligible dependence on the doping concentrations. The maximum external quantum efficiency of the fabricated blue OLED is 17.5%.

• 单位
  y; 中国科学院; 燕山大学