报告题目：Iso-structural Induced Ultralong Organic Phosphorescence  

报 告 人：新加坡国立大学Bin Liu教授

报告时间：2024年3月29日（周五）上午10点

报告地点：科技园1号楼发光国重N308报告厅

报告摘要：Commercial carbazole (Cz) has been widely used to synthesize organic functional materials, which are entwined with recent breakthroughs in ultralong organic phosphorescence, thermally activated delayed fluorescence, organic luminescent radicals, and organic semiconductor lasers. Recently, we discovered that different from commercial Cz, the fluorescence of lab-synthesized-Cz (Lab-Cz) is blue-shifted by 54 nm and the well-known room-temperature ultralong phosphorescence almost disappears. Detailed studies reveal the presence of a Cz isomer as the impurity, which is widespread in commercial Cz sources with <0.5 mol%. Ten representative Cz derivatives were resynthesized from the Lab-Cz and all failed to show the reported ultralong phosphorescence in the same crystal states. However, even 0.1 mol% isomer doping can recover the reported ultralong phosphorescence. The presence of the isomer in commercial carbazole tiggers us to re-examine the structure-property of many optically active materials. Interesting results have also been obtained for molecules with thermally activated delayed fluorescence and organic photosensitizers. 

报告人简介：Professor Bin Liu is Tan Chin Tuan Centennial Professor at the National University of Singapore (NUS). Bin graduated with bachelor’s degree from Nanjing University and a Ph.D. in Chemistry from NUS. She had postdoctoral training at the University of California, Santa Barbara before joining NUS in late 2005. Bin has been well-recognized for her contributions to polymer chemistry and organic nanomaterials for energy and biomedical applications. She is an international member of the US National Academy of Engineering. Since 2019, she has served as the Deputy Editor to launch and develop ACS Materials Letters, a flagship materials journal of the American Chemical Society.