联萘基手性发光材料的圆偏振发光

Circularly polarized luminescence of binaphthalyl chiral luminescent materials

本文综述了近年来基于联萘基结构的圆偏振发光材料的研究工作.从光致发光和电致发光两方面总结了不同体系下联萘基材料的圆偏振发光,为相关领域的研究者提供了设计思路,并对圆偏振发光材料的研究发展方向进行了展望.

Circularly polarized light(CPL) refers to the phenomenon that a chiral luminescence system emits left-handed or right-handed circularly polarized light when it is excited. It has great application prospects in three-dimensional display, chiral sensors, organic light-emitting diodes, spin information communication, biological detection and chemical probes. As early as 1948, the Soviet physicist Samoylov was the first to observe the CPL signal of the F-F electron energy level transition in sodium uranate crystals at liquid helium temperature. Professor Oosterhoff of Leiden University in the Netherlands applied CPL to the detection of molecular excited state structures for the first time. Since then, people have invested a lot of money and energy to develop circularly polarized luminescent materials. Early research mainly focused on the study of chiral rare earth metal complexes. Subsequently, the research gradually expanded to the fields of chiral non-lanthanide transition-metal complexes, chiral organic small molecules, chiral polymers and chiral supramolecular systems. Axial chiral binaphthyl compounds play an important role in the biological activity of many natural products, and they are also an important class of optically active compounds. Axial chirality is the distribution of two or more groups around the axis, and its distribution is such that the molecule can′t overlap with its mirror image, resulting in chirality. The biaryl skeleton is the most classic axial chiral molecule. This type of biaryl derivative has both axial chirality and electron-rich π-conjugated skeleton, so the molecule itself has CPL properties. When a luminophore with more special photoelectric properties is introduced into the biaryl skeleton, it is possible to further design and synthesize chiral luminescent molecules with better performance. This article reviews the research progress of binaphthyl chiral luminescent material CPL from two aspects: photoluminescence and electroluminescence. In the first part of the article, we introduced in detail the latest research progress of binaphthyl photo-circularly polarized luminescence system from chiral metal-organic complex materials and pure organic materials, and discussed the influence mechanism of binaphthyl group on circularly polarized luminescence under different systems. The study found that the conformation of the binaphthyl group, the micro-environment and the aggregation state of the system are important factors that affect the luminescence of CPL. The second part introduces the research progress of electro-circularly polarized luminescence, focusing on the two circularly polarized electroluminescence(CPEL) materials of aggregated chiral aggregation-induced emission luminophores(AIEgens) and chiral thermally active delayed fluorescence(CP-TADF) small molecules. And the corresponding molecular design strategies provide design ideas for researchers in related fields. Finally, the future research and development directions of circularly polarized luminescent materials are prospected.