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Long-Persistent Circularly Polarized Luminescence from a Host-Guest System Regulated by the Multiple Roles of a Gold(I)-Carbene Motif |
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| Authors: | Fei-Hu Yu Rui Jin Dr Xiaoyong Chang Dr Kai Li Prof?Dr Ganglong Cui Prof?Dr Yong Chen |
| Institution: | 1. Key Laboratory of Photochemical Conversion and Optoelectronic Materials &, CAS-HKU Joint Laboratory on New Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190 P.R. China
University of Chinese Academy of Sciences, Beijing, 100049 P.R. China;2. Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, Chemistry College, Beijing Normal University, Beijing, 100875 P.R. China;3. Department of Chemistry, Southern University of Science and Technology, Shenzhen, 518055 P.R. China;4. Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518055 P.R. China;5. Key Laboratory of Photochemical Conversion and Optoelectronic Materials &, CAS-HKU Joint Laboratory on New Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190 P.R. China |
| Abstract: | The promotion of intersystem crossing (ISC) is critical for achieving a high-efficiency long-persistent luminescence (LPL) from organic materials. However, the use of a transition-metal complex for LPL materials has not been explored because it can also shorten the emission lifetime by accelerating the phosphorescence decay. Here, we report a new class of LPL materials by doping a monovalent Au-carbene complex into a boron-embedded molecular host. The donor-acceptor systems exhibit photoluminescence with both high efficiencies (>57 %) and long lifetimes (ca. 40 ms) at room temperature. It is revealed that the Au atom promotes the population of low-lying triplet excited states of the host aggregate (T1*) which can be converted into the charge-transfer (CT) state, thereby resulting in afterglow luminescence. Moreover, the use of a chirality unit on the guest molecule results in the LPL being circularly polarized. This work illustrates that transition-metal complexes can be used for developing organic afterglow systems by exquisite control over the excited state mechanism. |
| Keywords: | Charge Transfer Heavy Atom Effect Host-Guest System Long-Persistent Luminescence Spin-Orbit Coupling |