The influence of 1H-benzo[f]indole (Bd) and its derivatives on room temperature phosphorescence (RTP) has raised great concern since they were found to significantly affect RTP of the extensively studied carbazole (Cz) derivatives. However, the role of Bd itself existing in Cz-based or other doping systems was still unclear. In order to clarify its intrinsic phosphorescent property, Bd was introduced as a guest into different organic matrixes including substituted Cz derivatives and polymers. The phosphorescence located in 560–620 nm was confirmed to be derived from Bd itself, which can be detected whatever Bd was doped in the crystal or amorphous state of Cz derivatives. The suitable energy gap between Cz derivatives and Bd is the key to achieve ultralong RTP of Bd. Additionally, when doped in polymers with plenty of hydrogen bonds, RTP of Bd with lifetime over 280 ms was easily obtained. Among them, Bd@PHEMA (poly(hydroxyethyl methacrylate) exhibited superior phosphorescence, with yellow afterglow lasting for over 2.5 s. Therefore, this work demonstrated that a new organic RTP phosphor, Bd, is discovered, and ultralong RTP of Bd can be achieved not only doped in Cz derivatives but also in polymers as the hosts.

1 H -benzo[ f的影响]吲哚 (Bd) 及其衍生物对室温磷光 (RTP) 的影响引起了人们的极大关注，因为它们被发现会显着影响广泛研究的咔唑 (Cz) 衍生物的 RTP。然而，Bd 本身在基于 Cz 或其他掺杂系统中的作用仍不清楚。为了阐明其固有的磷光特性，将 Bd 作为客体引入不同的有机基质中，包括取代的 Cz 衍生物和聚合物。位于 560-620 nm 的磷光被证实来自 Bd 本身，无论 Bd 掺杂在 Cz 衍生物的晶体或非晶态中，都可以检测到。Cz衍生物与Bd之间合适的能隙是实现Bd超长RTP的关键。此外，当掺杂在具有大量氢键的聚合物中时，很容易获得寿命超过 280 毫秒的 Bd RTP。其中，Bd@PHEMA（聚（甲基丙烯酸羟乙酯））表现出优异的磷光，黄色余辉持续时间超过 2.5 s。因此，这项工作证明了一种新的有机 RTP 荧光粉 Bd 的发现，并且可以实现 Bd 的超长 RTP不仅掺杂在 Cz 衍生物中，而且还掺杂在作为主体的聚合物中。