Han Xiao, Xia Chunlei, Wu Han, Xie Yadian, Li Rui, Sui Bowen, Yu Yue, Wang Bo, Yang Bai
State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
Angew Chem Int Ed Engl. 2025 Mar 17;64(12):e202422822. doi: 10.1002/anie.202422822. Epub 2025 Jan 21.
Carbonized polymer dots (CPDs) are a class of exceptional fluorescent materials with diverse applications. However, their photoluminescence (PL) mechanism remained enigmatic and controversial, hindering further development and application. While molecular fluorophores explain primary fluorescence in some CPDs, the overall PL of CPDs still cannot be fully explained, such as their excitation-dependent behaviors, let alone the modulation of PL. Besides, the extracted molecular fluorophores are dissociative, raising questions including the purity of CPDs and whether the PL of CPDs nanoparticles come from these molecular fluorophores. Here, the emission around 510 nm of citric acid-ethylenediamine CPDs (CA-EDA CPDs) was proved to be contributed by a molecular fluorophore, which evolved from another molecular fluorophore following the quantum confinement effect. Further research revealed the whole PL mechanism of CA-EDA CPDs to be the evolution and synergistic PL of multiple molecular fluorophores linked on CPDs nanoparticle. The evolution of molecular fluorophores had also been observed in another two systems, indicating the universality of this mechanism, and a new approach for regulating the optical properties of CPDs was put forward inspired by this mechanism. This study not only refined the PL mechanism but also paved the way for future advancements of CPDs.
碳化聚合物点（CPDs）是一类具有多种应用的特殊荧光材料。然而，它们的光致发光（PL）机制仍然神秘且存在争议，这阻碍了其进一步的发展和应用。虽然分子荧光团解释了某些CPDs中的主要荧光，但CPDs的整体PL仍无法得到充分解释，例如它们的激发依赖行为，更不用说PL的调制了。此外，提取的分子荧光团是解离的，这引发了包括CPDs的纯度以及CPDs纳米颗粒的PL是否来自这些分子荧光团等问题。在此，柠檬酸 - 乙二胺CPDs（CA - EDA CPDs）在510 nm附近的发射被证明是由一种分子荧光团贡献的，该荧光团遵循量子限制效应从另一种分子荧光团演化而来。进一步的研究揭示了CA - EDA CPDs的整个PL机制是CPDs纳米颗粒上连接的多个分子荧光团的演化和协同PL。在另外两个体系中也观察到了分子荧光团的演化，表明了该机制的普遍性，并受此机制启发提出了一种调节CPDs光学性质的新方法。这项研究不仅完善了PL机制，也为CPDs的未来发展铺平了道路。
