Ye Qiang, Zheng Feng, Zhang Enqi, Bisoyi Hari Krishna, Zheng Shuyuan, Zhu Dandan, Lu Qinghua, Zhang Hailiang, Li Quan
Key Laboratory of Polymeric Materials and Application Technology of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, School of Chemistry, Xiangtan University Xiangtan 411105 China.
Advanced Materials and Liquid Crystal Institute, Chemical Physics Interdisciplinary Program, Kent State University Kent OH 44242 USA
Chem Sci. 2020 Aug 17;11(36):9989-9993. doi: 10.1039/d0sc04179c.
Development of functional materials capable of exhibiting chirality tunable circularly polarized luminescence (CPL) is currently in high demand for potential technological applications. Herein we demonstrate the formation of both left- and right-handed fluorescent helical superstructures from each enantiomer of a chiral tetraphenylethylene derivative through judicious choice of the solution processing conditions. Interestingly, both the aggregation induced emission active enantiomers exhibit handedness inversion of their supramolecular helical assemblies just by varying the solution polarity without any change in their molecular chirality. The resulting helical supramolecular aggregates from each enantiomer are capable of emitting circularly polarized light, thus enabling both right- and left-handed CPL from a single chiral material. The left- and right-handed supramolecular helical aggregates in the dried films have been characterized using spectroscopy, scanning electron microscopy, and transmission electron microscopy techniques. These new chiral aggregation induced emission compounds could find applications in devices where CPL of opposite handedness is required from the same material and would facilitate our understanding of the formation of helical assemblies with switchable supramolecular chirality.
目前，对于潜在的技术应用而言，开发能够展现手性可调圆偏振发光（CPL）的功能材料的需求很高。在此，我们通过明智地选择溶液加工条件，证明了由手性四苯基乙烯衍生物的每种对映体形成左旋和右旋荧光螺旋超结构。有趣的是，这两种聚集诱导发光活性对映体仅通过改变溶液极性就可使其超分子螺旋组装体的手性发生反转，而其分子手性并无任何变化。每种对映体产生的螺旋超分子聚集体能够发射圆偏振光，从而使单一手性材料能够实现左旋和右旋CPL。已使用光谱学、扫描电子显微镜和透射电子显微镜技术对干膜中的左旋和右旋超分子螺旋聚集体进行了表征。这些新型手性聚集诱导发光化合物可应用于需要同一材料产生相反手性CPL的器件中，并将有助于我们理解具有可切换超分子手性的螺旋组装体的形成。
