School of Chemical Sciences, National Centre for Sensor Research, Dublin City University Glasnevin, Dublin 9, Ireland.
Institute of Physics and Applied Computer Science, Faculty of Applied Physics and Mathematics, Gdańsk University of Technology, Narutowicza 11/12, 80233, Gdańsk, Poland.
Chemistry. 2023 Apr 25;29(24):e202300239. doi: 10.1002/chem.202300239. Epub 2023 Mar 29.
BODIPY heterochromophores, asymmetrically substituted with perylene and/or iodine at the 2 and 6 positions were prepared and investigated as sensitizers for triplet-triplet annihilation up conversion (TTA-UC). Single-crystal X-ray crystallographic analyses show that the torsion angle between BODIPY and perylene units lie between 73.54 and 74.51, though they are not orthogonal. Both compounds show intense, charge transfer absorption and emission profiles, confirmed by resonance Raman spectroscopy and consistent with DFT calculations. The emission quantum yield was solvent dependent but the emission profile remained characteristic of CT transition across all solvents explored. Both BODIPY derivatives were found to be effective sensitizers of TTA-UC with perylene annihilator in dioxane and DMSO. Intense anti-Stokes emission was observed, and visible by eye from these solvents. Conversely, no TTA-UC was observed from the other solvents explored, including from non-polar solvents such as toluene and hexane that yielded brightest fluorescence from the BODIPY derivatives. In dioxane, the power density plots obtained were strongly consistent with TTA-UC and the power density threshold, the I value (the photon flux at which 50 % of ΦTTAUC is achieved), for B2PI was observed to be 2.5x lower than of B2P under optimal conditions, an effect ascribed to the combined influence of spin-orbit charge transfer intersystem crossing (SOCT-ISC) and heavy metal on the triplet state formation for B2PI.
BODIPY 生色团，在 2 位和 6 位不对称取代了苝和/或碘，被制备并作为三重态-三重态湮灭上转换（TTA-UC）的敏化剂进行了研究。单晶 X 射线晶体学分析表明，BODIPY 和苝单元之间的扭转角在 73.54 和 74.51 之间，尽管它们不是正交的。这两种化合物都表现出强烈的、电荷转移吸收和发射谱，这一点通过共振拉曼光谱得到了证实，并且与 DFT 计算结果一致。发射量子产率取决于溶剂，但发射谱仍然是所有探索溶剂中 CT 跃迁的特征。两种 BODIPY 衍生物都被发现是有效的 TTA-UC 敏化剂，在二氧六环和 DMSO 中有苝湮灭剂。在这些溶剂中观察到强烈的反斯托克斯发射，肉眼可见。相反，在其他探索的溶剂中没有观察到 TTA-UC，包括非极性溶剂，如甲苯和己烷，这些溶剂从 BODIPY 衍生物中产生最亮的荧光。在二氧六环中，获得的功率密度图与 TTA-UC 非常一致，并且 B2PI 的功率密度阈值（I 值，即达到 50% ΦTTAUC 的光子通量）观察到比 B2P 低 2.5 倍，这一效应归因于自旋轨道电荷转移系间窜越（SOCT-ISC）和重金属对 B2PI 三重态形成的综合影响。
