The development of multiple resonance thermally activated delayed fluorescence (MR-TADF) materials possessing narrow emission spectra has attracted significant attention as emitters for high colour purity organic light emitting diodes (OLEDs). In this work, a simple design strategy is introduced to construct an MR-TADF emitter, DDiKTa, through dimerization of the known MR-TADF emitter DiKTa. This design permits concentration quenching to be largely suppressed, which is a known weakness of previously reported MR-TADF emitters. OLEDs based on DDiKTa show an EQE_max of 19% at a doping concentration of 9 wt%. The electroluminescence spectrum is red-shifted into the green, producing a rare example of a green-emitting MR-TADF OLED.

中文翻译：

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基于多环胺/羰基体系的扩展多共振TADF发射体的设计

作为高色纯度有机发光二极管（OLED）的发射器，具有窄发射光谱的多重共振热激活延迟荧光（MR-TADF）材料的开发引起了广泛的关注。在这项工作中，一个简单的设计策略被引入到构建MR-TADF发射器，DDiKTa，通过已知的MR-TADF发射的二聚DiKTa。这种设计可以大大抑制浓度猝灭，这是以前报道的MR-TADF发射器的已知缺点。在9 wt％的掺杂浓度下，基于DDiKTa的OLED的EQE_最大值为19％。电致发光光谱从红移到绿，从而产生了发绿光的MR-TADF OLED的罕见例子。