Li Heyang, Ma Huili, Zhang Peng, An Zhongfu, He Xiaoming
Key Laboratory of Applied Surface and Colloid Chemistry (Ministry of Education), School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710119, P.R. China.
Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211800, P.R. China.
Angew Chem Int Ed Engl. 2025 Feb 10;64(7):e202419366. doi: 10.1002/anie.202419366. Epub 2024 Nov 27.
Developing pure organic materials with ultralong lifetimes and balanced quantum efficiency is attractive but challenging. In this study, we propose a novel strategy to investigate external heavy atoms by linking molecular emitters with halogen through a flexible alkyl chain. X-ray crystal analysis clearly reveal the halogen C-X-π interactions, which can be tuned by halogen donors, as well as the distance and geometry between them. Impressively, DOPTZ-C3Cl featuring a chloride atom as donor, exhibits a balanced long phosphorescence lifetime of 1351 ms and a phosphorescence quantum yield of 10.1 %. We also first demonstrate that Cl can induce more positive effect than heavier halogens (Br and I) on prolonging the lifetime. We envisage that the present study will expedite new molecular design to manipulate the room temperature phosphorescence via external heavy atom effect, and highlight a special C-Cl⋅⋅⋅π interaction for the development of ultralong phosphorescent materials.
开发具有超长寿命和平衡量子效率的纯有机材料既具有吸引力又具有挑战性。在本研究中，我们提出了一种新颖的策略，通过柔性烷基链将分子发射体与卤素相连来研究外部重原子。X射线晶体分析清楚地揭示了卤素C-X-π相互作用，其可由卤素供体调节，以及它们之间的距离和几何形状。令人印象深刻的是，以氯原子作为供体的DOPTZ-C3Cl表现出1351 ms的平衡长磷光寿命和10.1 %的磷光量子产率。我们还首次证明，在延长寿命方面，Cl比更重的卤素（Br和I）能产生更积极的效果。我们设想，本研究将加速通过外部重原子效应来操纵室温磷光的新分子设计，并突出一种特殊的C-Cl⋅⋅⋅π相互作用以用于超长磷光材料的开发。
