Hu Wenbin, Fan Mingyue, Zhang Xian-Fu, Li Mengmeng, Li Guoying
Department of Chemical Engineering, Hebei Normal University of Science and Technology, Qinhuangdao, Hebei Province 066004, China.
Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong Province 518055, China; MPC Tech, MPC Technologies, Hamilton, ON L8S 3H4, Canada.
Spectrochim Acta A Mol Biomol Spectrosc. 2023 Mar 15;289:122222. doi: 10.1016/j.saa.2022.122222. Epub 2022 Dec 7.
meso-RNH (R = CH, CH, PhCH, H, and Ph) substituted BODIPY compounds have been prepared to examine their photophysical properties and photosensitizing abilities. We have measured the UV-vis absorption, steady state and time resolved fluorescence, excited triplet state formation using laser flash photolysis, singlet oxygen generation ability using chemical trapping method. The results show that the presence of meso-RNH leads to large blue shift of absorption and emission wavelength, remarkable decrease in fluorescence quantum yield and lifetime values, and significant increase in singlet oxygen formation quantum yield. Quantum chemical calculation also reveals the photoinduced charge transfer (PCT) mechanism. We conclude that property changes are due to: 1) S and S geometry, 2) ground state structural isomerization, and 3) intramolecular PCT. These results and mechanisms are helpful for designing new functional materials.
已制备了中位-RNH（R = CH、CH、PhCH、H和Ph）取代的BODIPY化合物，以研究其光物理性质和光敏能力。我们测量了紫外可见吸收、稳态和时间分辨荧光、使用激光闪光光解测定激发三重态的形成、使用化学捕获法测定单线态氧生成能力。结果表明，中位-RNH的存在导致吸收和发射波长发生大幅蓝移，荧光量子产率和寿命值显著降低，单线态氧形成量子产率显著增加。量子化学计算也揭示了光诱导电荷转移（PCT）机制。我们得出结论，性质变化归因于：1）S和S几何结构，2）基态结构异构化，3）分子内PCT。这些结果和机制有助于设计新型功能材料。
