Thermally activated delayed fluorescent (TADF) emitters are usually designed as donor–acceptor structures with large dihedral angles, which tend to incur low fluorescent efficiency, and therefore, through molecular design various strategies have been proposed to increase the efficiency of emitters; however, few studies have compared these strategies in one TADF system. In this study, a novel TADF molecule, [4‐(9,9‐diphenylacridin‐10‐yl)phenyl](phenyl)methanone (BP‐DPAC), was designed as a prototype, and two derivatives, BP‐Ph‐DPAC and DPAC‐BP‐DPAC, were also prepared to represent two common approaches to enhance TADF performance. Compared with the maximum external quantum efficiency (EQE) of 6.82 % for BP‐DPAC, organic light‐emitting diodes (OLED) devices based on DPAC‐BP‐DPAC exhibited enhanced TADF properties with the highest maximum EQE of 18.67 %, owing to an additional diphenylacridine donor, whereas BP‐Ph‐DPAC showed non‐TADF properties and exhibited the lowest EQE of 4.25 %, owing to the insertion of a phenyl ring between donor and acceptor.

中文翻译：

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通过分子构成调节A啶-二苯甲酮衍生物热活化延迟荧光性能的方法学研究

通常将热激活延迟荧光（TADF）发射器设计为具有大二面角的施主-受体结构，这往往会导致较低的荧光效率，因此，通过分子设计，已提出了各种策略来提高发射器的效率。但是，很少有研究在一个TADF系统中比较这些策略。在这项研究中，一个新的TADF分子[4-（9,9-二苯基ac啶啶-10-基）苯基]（苯基）甲酮（BP-DPAC）被设计为原型，并且两个衍生物为BP-Ph-DPAC和DPAC-BP-DPAC也准备代表两种常见的增强TADF性能的方法。与BP‐DPAC的最大外部量子效率（EQE）为6.82％相比，基于DPAC-BP-DPAC的有机发光二极管（OLED）器件表现出增强的TADF性能，最大的最大EQE为18.67％，这归因于额外的二苯基ac啶供体，而BP-Ph-DPAC显示出非TADF性能并表现出由于在供体和受体之间插入苯环，所以EQE最低，为4.25％。