Mao Zhu, Yang Zhan, Xu Chao, Xie Zongliang, Jiang Long, Gu Feng Long, Zhao Juan, Zhang Yi, Aldred Matthew P, Chi Zhenguo
PCFM Lab , GDHPPC Lab , Guangdong Engineering Technology , Research Center for High-performance Organic and Polymer Photo-electric, Functional Films , State Key Laboratory of OEMT , School of Chemistry , Sun Yat-Sen University , Guangzhou 510275 , PR China . Email:
Key Laboratory of Theoretical Chemistry of Environment , Ministry of Education , School of Chemistry & Environment , South China Normal University , Guangzhou 510006 , PR China.
Chem Sci. 2019 Jun 24;10(31):7352-7357. doi: 10.1039/c9sc02282a. eCollection 2019 Aug 21.
Due to inefficient molecular design strategies, two-photon-excited ultralong organic room temperature phosphorescence (TPUOP) has not yet been reported in single-component materials. Herein, we present an innovative design method by dual-channel triplet harvesting to obtain the first bright TPUOP molecule with a lifetime of 0.84 s and a quantum efficiency of 16.6%. In compound the donor and acceptor units are connected at the position of benzophenone, showing intramolecular space charge transfer. Therefore, the two-photon absorption ability is improved due to the enhanced charge transfer character. Moreover, the small energy gap boosts dual-channel triplet harvesting ultralong thermally activated delayed fluorescence and H-aggregation phosphorescence, which suppresses the long-lived triplet concentration quenching. Through two-photon absorption, a near-infrared laser (808 nm) is able to trigger the obvious ultralong emission under ambient conditions. This research work provides valuable guidance for designing near-infrared-excited ultralong organic room temperature phosphorescence materials.
由于分子设计策略效率低下，单一组分材料中尚未报道双光子激发的超长有机室温磷光（TPUOP）。在此，我们提出了一种通过双通道三重态捕获的创新设计方法，以获得首个具有0.84秒寿命和16.6%量子效率的明亮TPUOP分子。在化合物中，供体和受体单元在二苯甲酮的位置相连，呈现分子内空间电荷转移。因此，由于电荷转移特性增强，双光子吸收能力得到提高。此外，小的能隙促进了双通道三重态捕获、超长热激活延迟荧光和H聚集磷光，从而抑制了长寿命三重态浓度猝灭。通过双光子吸收，近红外激光（808 nm）能够在环境条件下触发明显的超长发射。这项研究工作为设计近红外激发的超长有机室温磷光材料提供了有价值的指导。
