Ye Zi, Xia Wen, Wang Guangming, Wu Guoyi, Gao Hongxin, Xu Biao, Zhang Kaka
State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis, Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules, Ningbo Zhongke Creation Center of New Materials, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, P. R. China.
Adv Sci (Weinh). 2025 Jun 30:e01558. doi: 10.1002/advs.202501558.
Organic long persistent luminescence (OLPL) materials feature power law emission decay and minutes-/hours-long afterglow durations because of retarded charge recombination. Unlike conventional room-temperature phosphorescence (RTP) and thermally activated delayed fluorescence (TADF) afterglow, the emergence of OLPL must include a charge separation process in its photophysical mechanism; consequently, the reported OLPL examples are much fewer than conventional afterglow materials. The incorporation of an electron donor or acceptor is conceived to interact with the long-lived excited state in conventional afterglow system, aiming to induce charge separation. Here, the study first builds two-component RTP/TADF afterglow systems composed of difluoroboron β-diketonate (BFbdk) dopants and organic crystalline matrices, and then introduces an electron-donating component into the two-component BFbdk-matrix systems to enable the charge separation processes. The resultant three-component materials exhibit visible-light-excitable OLPL afterglow lasting for several hours under ambient condition. Leveraging the efficient harvesting of singlet/triplet excitons by BFbdk and the protective environment provided by the crystalline matrix, the three-component materials exhibit an estimated OLPL efficiency of ≈10% and display OLPL brightness comparable to inorganic SrAlO/Eu, Dy materials. Furthermore, the obtained OLPL materials show promising applications in afterglow displays and information storage, marking a significant step toward practical implementations of organic afterglow materials.
有机长余辉发光（OLPL）材料由于电荷复合延迟而具有幂律发射衰减和持续数分钟/数小时的余辉持续时间。与传统的室温磷光（RTP）和热激活延迟荧光（TADF）余辉不同，OLPL的出现必须在其光物理机制中包含电荷分离过程；因此，已报道的OLPL实例比传统余辉材料少得多。在传统余辉体系中引入电子供体或受体被认为可以与长寿命激发态相互作用，以诱导电荷分离。在此，该研究首先构建了由二氟硼β-二酮（BFbdk）掺杂剂和有机晶体基质组成的双组分RTP/TADF余辉体系，然后将给电子组分引入双组分BFbdk-基质体系中以实现电荷分离过程。所得的三组分材料在环境条件下表现出可见光激发的OLPL余辉，持续数小时。利用BFbdk对单重态/三重态激子的高效捕获以及晶体基质提供的保护环境，三组分材料的OLPL效率估计约为10%，并且其OLPL亮度与无机SrAlO/Eu、Dy材料相当。此外，所获得的OLPL材料在余辉显示和信息存储方面显示出有前景的应用，标志着有机余辉材料实际应用迈出了重要一步。
