Aggregation-induced emission enhancement materials with large red shifts and their self-assembled crystal microstructures
作者:Qing Dai、Weimin Liu、Lintao Zeng、Chun-Sing Lee、Jiasheng Wu、Pengfei Wang
DOI:10.1039/c1ce05035d
日期:——
Two simple intramolecular charge transfer compounds (BzBMN and BzFAN), derived from 2-benzyloxy-4-diethylaminobenzaldehyde, have been synthesized. Unlike typical AIEE molecules, the enhanced emission of these compounds in the solid state is accompanied by large red shifts in emission wavelength. Absorption and photoluminescence (PL) spectra of the compounds in solution, film and the X-ray single crystal structures were investigated to understand the mechanism of enhanced emission in the solid state. The results indicate that the bathochromic shift excimer-like emissions originated from dimers induced by the dipole–dipole interaction and long-range ordered arrangement (e.g. J-aggregation), and the enhanced emission is attributed to the restriction of intramolecular rotations caused by multiple intermolecular hydrogen bonding interactions. In addition, it was also observed that BzBMN and BzFAN can facilely form single crystal microbelts and microtubes by a simple reprecipitation method.
我们合成了两种简单的分子内电荷转移化合物(BzBMN 和 BzFAN),它们来自 2-苄氧基-4-二乙氨基苯甲醛。与典型的 AIEE 分子不同,这些化合物在固态下增强的发射伴随着发射波长的大幅红移。研究人员对溶液、薄膜和 X 射线单晶结构中化合物的吸收光谱和光致发光(PL)光谱进行了研究,以了解固态下发射增强的机理。结果表明,浴色偏移的准分子样发射源于偶极-偶极相互作用和长程有序排列(如 J-聚集)诱导的二聚体,而发射增强则归因于分子间多种氢键相互作用导致的分子内旋转限制。此外,还观察到 BzBMN 和 BzFAN 可通过简单的再沉淀法方便地形成单晶微带和微管。