| Title | Crystal-state quad-mode triplet emissions of D-A-A '-AIEE and visible-light-excited persistent phosphorescence |
| Authors | Liu, Jianwei Ma, Zhimin Li, Zewei Liu, Yan Fu, Xiaohua Jiang, Hong Ma, Zhiyong Jia, Xinru |
| Affiliation | Beijing Univ Chem Technol, Coll Chem Engn, Beijing State Key Lab Organ Inorgan Composites, Beijing 100029, Peoples R China Natl High Tech Ind Dev Zone Jingdezhen, Jingdezhen 333000, Peoples R China Peking Univ, Minist Educ, Coll Chem & Mol Engn, Beijing Natl Lab Mol Sci,Key Lab Polymer Chem & P, Beijing 100871, Peoples R China |
| Issue Date | Apr-2021 |
| Publisher | DYES AND PIGMENTS |
| Abstract | Herein, we succeed in finding crystal-state quad-mode triplet emissions through the concept of integration of thermally activated exciton release from T-1* and introducing intramolecular electron coupling. Two new D-A-A'D type carbazol-nicotinamide isomers (P1 and P2) with the pyridine ring as the core are synthesized. The crowded D-A-A'-D structure makes P1 and P2 in a highly twisted state, which is conducive to lowering the Delta E-ST and E-TD. Excitingly, P1 and P2 achieve the crystal-state quad-mode triplet emissions, including ultralong room temperature phosphorescence from T-1*, TADP from T-1 via thermally activated exciton release (TAER), the original molecular phosphorescence from T-1 and TADF from S-1 via TAER and reverse intersystem crossing (RISC). Especially, the long-lived emissions of P1 have a rather high quantum yield of 34.3%. The intramolecular electron coupling is observed in the single crystal, verifying the original T-1 phosphorescence. The Delta E-ST and E-TD of the crystals can be calculated experimentally to be 0.19/0.18 eV and 0.19/0.20 eV, respectively, for P1 and P2. And the TAER and RISC process is validated by temperature-dependent experiment. Besides, the P2 crystals manifest fascianting visible-light-excited persistent phosphorescence and P1 shows remarkable AIEE property. To the best of our knowledge, it is the first time to find crystal-state quad-mode triplet emissions at mom temperature experimentally. This study is a breakthrough in the development of multi-mode phosphorescence mechanism. |
| URI | http://hdl.handle.net/20.500.11897/609377 |
| ISSN | 0143-7208 |
| DOI | 10.1016/j.dyepig.2021.109178 |
| Indexed | SCI(E) |
| Appears in Collections: | 化学与分子工程学院 高分子化学与物理教育部重点实验室 |
