Shao Juan, Chang Yongxin, Wang Hao, Qin Haijuan, Li Qiongya, Yang Ting, Tang Mingliang, Wang Guoxiong, Chen Shuai, Qing Guangyan
Research Center for Analytical Sciences, Department of Chemistry, College of Sciences, Northeastern University, Shenyang, 110819, P. R. China.
State Key Laboratory of Medical Proteomics, CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P. R. China.
Small. 2025 Aug;21(31):e2502383. doi: 10.1002/smll.202502383. Epub 2025 Jun 4.
Pursuing innovative modulation strategies and high asymmetry factors (g) remains a cornerstone in developing circularly polarized luminescence (CPL) materials. Conventional approaches employ either bottom-up chiral small molecule self-assembly or top-down co-assembly of achiral luminophores with supramolecular chiral templates (e.g., cellulose nanocrystals (CNCs), liquid crystals). These templates act as pre-engineered "molds" to align achiral emitters within chiral matrices. However, co-assembling chiral small molecules with such templates remains underexplored, challenged by complex protocols and limited assembly control, raising fundamental questions about supramolecular chiral interplay. Herein, we elucidate the co-assembly and interplay between chiral aggregation-induced emission (AIE) molecules (PN-Phe halides) and CNCs. Halide ions (F, Cl, Br, and PF ) profoundly modulate PN-Phe self-assembly, dictating distinct morphologies, packing, chiroptical signals, fluorescent quantum yields (QY), and lifetimes. PN-Phe-Cl exhibits the highest g (-4.1 × 10), versus PN-Phe-Br (-2.8 × 10). Strikingly, co-assembly into CNC-PVA-PN-Phe-X- (CPP-X-) composite films reverse this trend: CPP-Cl achieves an exceptional g of -0.43, contrasting sharply with CPP-Cl (-3.1 × 10). The multiple color variations and potential application in anti-counterfeiting demonstrate the advantages of this co-assembly strategy. This work highlights the significant role of assembly patterns in constructing advanced CPL materials, revealing that halide ions could serve as effective modulators for CPL.
追求创新的调制策略和高不对称因子（g）仍然是开发圆偏振发光（CPL）材料的基石。传统方法要么采用自下而上的手性小分子自组装，要么采用非手性发光体与超分子手性模板（如纤维素纳米晶体（CNC）、液晶）的自上而下的共组装。这些模板充当预先设计的“模具”，以使非手性发射体在手性基质中排列。然而，将手性小分子与此类模板共组装的研究仍未充分开展，受到复杂方案和有限的组装控制的挑战，这引发了有关超分子手性相互作用的基本问题。在此，我们阐明了手性聚集诱导发光（AIE）分子（PN-Phe卤化物）与CNC之间的共组装和相互作用。卤离子（F、Cl、Br和PF）深刻地调节PN-Phe的自组装，决定了不同的形态、堆积、手性光学信号、荧光量子产率（QY）和寿命。PN-Phe-Cl表现出最高的g（-4.1×10），而PN-Phe-Br为（-2.8×10）。引人注目的是，共组装成CNC-PVA-PN-Phe-X-（CPP-X-）复合膜则逆转了这一趋势：CPP-Cl实现了-0.43的优异g值，与CPP-Cl（-3.1×10）形成鲜明对比。多种颜色变化以及在防伪方面的潜在应用证明了这种共组装策略的优势。这项工作突出了组装模式在构建先进CPL材料中的重要作用，揭示了卤离子可作为CPL的有效调节剂。
