The development of polymer‐based luminescent materials with efficient photoactivated ultralong organic phosphorescence (UOP) is of great importance but very challenging. Herein, a new class of organic phosphorescent luminogens is constructed by attaching phenyl rings and/or ethyl benzoates to the nitrogen atoms of a planar aromatic heterocycle pyrrolodiindole (PDI). The compounds show a significant elevation in phosphorescence emission capability after incorporating the ester group(s). However, they cannot produce room‐temperature phosphorescence in the crystalline state. These observations are identified to be associated with the formation of dimers and excimers and the motions of substituents within the molecules. In this context, the PDI derivatives are doped into epoxy polymers with compact and permanent 3D covalent networks. The resulting polymer films show reversible photoactivated UOP under ambient conditions, with quantum yields and lifetimes of up to 24.4% and 2.03 s, respectively, thereby enabling high‐quality and erasable light printing and multi‐level anti‐counterfeiting applications. In addition, they also exhibit excellent water and chemical resistance. This work is conducive to understanding the generation and decay mechanisms of the triplet excitons of organic luminophores with planar aromatic heterocycles in the crystalline state and provides a direction for the development of high‐performance photoactivated UOP materials.

中文翻译：

---

阐明结晶引起的磷光淬灭机制，以实现高质量光打印的高效光激活持久发光

开发具有高效光活化超长有机磷光（UOP）的聚合物基发光材料非常重要，但也非常具有挑战性。本文中，通过将苯环和/或苯甲酸乙酯连接到平面芳香杂环吡咯二吲哚（PDI）的氮原子上构建了一类新型有机磷光发光剂。该化合物在掺入酯基后显示出磷光发射能力的显着提高。然而，它们不能在结晶状态下产生室温磷光。这些观察结果被认为与二聚体和准分子的形成以及分子内取代基的运动有关。在这种情况下，PDI 衍生物被掺杂到具有紧凑且永久的 3D 共价网络的环氧聚合物中。所得聚合物薄膜在环境条件下表现出可逆光活化UOP，量子产率和寿命分别高达24.4%和2.03秒，从而实现高质量、可擦除的光印刷和多级防伪应用。此外，它们还具有出色的耐水性和耐化学性。该工作有利于理解晶态平面芳香杂环有机发光体三线态激子的产生和衰变机制，为高性能光活化UOP材料的发展提供方向。