Synthesis, Aggregation-Induced Emission, and Liquid Crystalline Structure of Tetraphenylethylene–Surfactant Complex via Ionic Self-Assembly

A novel tetraphenylethylene material with liquid crystalline (LC) helical structure and aggregation-induced emission (AIE) property was prepared by ionic self-assembly (ISA). The AIE activity, phase behavior, self-assembly structure, and molecular packing behavior of the complex were then elucidated via a combination of different experimental techniques such as UV–vis absorption spectra, photoluminescence spectra, differential scanning calorimetry, polarized optical microscopy, one- and two-dimensional X-ray diffraction, and Fourier transform infrared spectroscopy. The experimental results reveal that the ISA complex possesses high-efficiency luminescent property with quantum yield as high as 46% in solid state. Meanwhile, the complex could self-assemble into different interesting structures which are sensitive to peripheral chain motions. During heating, the complex takes a low-ordered helical supramolecular structure at ambient temperature and then forms another LC phase with high-ordered helical molecular stacking. These ordered hierarchical structures, in combination with the liquid crystallinity and excellent AIE property of the ISA complex, make it a promising material for fabrication of luminescent devices.