Ai Lin, Xiang Wenjuan, Li Zhan-Wei, Liu Huimin, Xiao Jiping, Song Haoqiang, Yu Jingkun, Song Ziqi, Zhu Kai, Pan Zhuohan, Wang Haolin, Lu Siyu
College of Chemistry, Pingyuan Laboratory, Zhengzhou University, 450001, Zhengzhou, China.
Angew Chem Int Ed Engl. 2024 Dec 2;63(49):e202410988. doi: 10.1002/anie.202410988. Epub 2024 Oct 30.
Circularly polarized luminescence (CPL) has numerous applications in optical data storage, quantum computing, bioresponsive imaging, liquid crystal displays, and backlights in three-dimensional (3D) displays. In addition to their competitive optical properties, carbon dots (CDs) benefit from simple and low-cost preparation, facile post-modification, and excellent resistance to photo- and chemical bleaching after carbonization. Combining the superior optical performance with polarization peculiarities through hierarchical structure engineering is imperative for the development of CDs. In this study, hydrophobic interactions of aromatic ligands, which participate in the surface-ligand post-modification process on the ground-state chiral carbon core, are employed to drive the oriented assembly. Furthermore, the residual chiral amides on CDs form multiple hydrogen bonds during gradual aggregation, causing the assembled materials to form an asymmetric bending structure. Superficial ligands interfere with the optical dynamics of the exciton radiation transition and stabilize the excited state of the assembled materials to achieve a circularly polarized signal. The linkage ligands overcome the frequent aggregation-induced quenching phenomenon that present difficulties in conventional CDs, facilitate the assembly of self-supporting films, and improve chiral optical expression. The full-color and white CPL are manipulated by simply adjusting the functional groups of the ligands, which also illustrates the versatility of the post-modification strategy. Finally, large chiral flexible films and multicolor chiral light-emitting diodes based on the stable chiral powder phosphors were constructed, thereby providing feasible materials and technical support for flexible 3D displays.
圆偏振发光（CPL）在光学数据存储、量子计算、生物响应成像、液晶显示器以及三维（3D）显示器的背光灯等领域有众多应用。除了具有优异的光学性能外，碳点（CDs）还具有制备简单、成本低、易于后修饰以及碳化后具有出色的抗光漂白和化学漂白性能等优点。通过分级结构工程将优异的光学性能与偏振特性相结合对于碳点的发展至关重要。在本研究中，利用参与基态手性碳核表面配体后修饰过程的芳香族配体的疏水相互作用来驱动定向组装。此外，碳点上残留的手性酰胺在逐渐聚集过程中形成多个氢键，导致组装材料形成不对称弯曲结构。表面配体干扰激子辐射跃迁的光学动力学并稳定组装材料的激发态以实现圆偏振信号。连接配体克服了传统碳点中常见的聚集诱导猝灭现象，促进了自支撑膜的组装，并改善了手性光学表达。通过简单地调整配体的官能团来操控全色和白色CPL，这也说明了后修饰策略的通用性。最后，基于稳定的手性粉末磷光体构建了大型手性柔性薄膜和多色手性发光二极管，从而为柔性3D显示器提供了可行的材料和技术支持。
