Exciplex has drawn attention because of its great potential for use as a host in organic light‐emitting diodes (OLEDs). Here a novel exciplex host formed with 3,3′‐di(9H‐carbazol‐9‐yl) biphenyl (m‐CBP) and 4,6‐bis (3,5‐di(pyridin‐4‐yl) phenyl)‐2‐phenylpyrimidine (B4PyPPM) is achieved. By utilizing m‐CBP:B4PyPPM exciplex host, blue, cyan, green, and red phosphorescent OLEDs exhibit maximum external quantum efficiencies (EQEs) of 26.2%, 26.1%, 24.7%, and 26.5%, respectively. Moreover, single‐emitting layer (EML) white organic light‐emitting devices (WOLEDs) are achieved by doping blue and red phosphorescent emitters, which exhibit high maximum EQEs of 23.9% and 26.9%. Even at a practical brightness of 5000 cd m⁻², the two WOLEDs still keep high EQEs of 19.1% and 21.0%, respectively. Furthermore, multiple‐EML WOLEDs are also constructed with efficiencies of 18.9% and 21.0% at the practical brightness of 5000 cd m⁻². The devices show extremely stable white emission with small Commission Internationale de L'Eclairage (CIE) coordinate varying range of (±0.001, ± 0.000) from 100 to 100 00 cd m⁻². The outstanding features presented here can provide a good reference for future design of high‐performance WOLEDs.

中文翻译：

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基于Exciplex主机的白色OLED，在5000 cd m-2处的EQE为21％，并且具有超高的色彩稳定性

Exciplex因其在有机发光二极管（OLED）中用作宿主的巨大潜力而​​备受关注。这是由3,3'-二（9 H-咔唑-9-基）联苯（m-CBP）和4,6-双（3,5-二（吡啶-4-基）苯基）形成的新型激基复合物宿主实现了-2-苯基嘧啶（B4PyPPM）。通过使用m-CBP：B4PyPPM激基复合物主体，蓝色，青色，绿色和红色磷光OLED分别具有26.2％，26.1％，24.7％和26.5％的最大外部量子效率（EQE）。此外，通过掺杂蓝色和红色磷光发光体可实现单发光层（EML）白色有机发光器件（WOLED），其最大EQE分别高达23.9％和26.9％。即使在5000 cd m ^-2的实际亮度下，这两个WOLED仍然分别保持19.1％和21.0％的高EQE。此外，在实际亮度为5000 cd m ^-2的情况下，还构建了效率分别为18.9％和21.0％的多EML WOLED 。该设备显示出非常稳定的白光发射，并且从100到100 00 cd m ^-2的小国际照明委员会（CIE）坐标变化范围为（±0.001，±0.000）。此处介绍的出色功能可以为高性能WOLED的未来设计提供良好的参考。