近日，华南农业大学庄健乐及其团队用纳米晶体中的碳点在溶液中实现室温磷光。相关论文于2025年2月5日发表在《德国应用化学》杂志上。

在该研究中，小组报告了通过高温共沉淀法一步将柠檬酸盐衍生的碳点（CDs）包封到NaYF₄纳米晶体中，从而在溶液中实现了自发磷光。综合表征表明，CDs的三重态发射与CDs中C=O的丰度、CDs周围离子键网络的形成以及NaYF₄纳米晶体的空间约束和猝灭抑制作用有关。

值得注意的是，通过对NaYF₄纳米晶体进行简单的表面调制，可以很容易地实现CDs@NaYF₄从疏水性到亲水性的转变，这使得CDs的室温磷光（RTP）可以在极性或非极性溶剂中保持。此外，CDs@NaYF₄在不同的pH环境下均表现出稳定的余辉，表明其具有优异的稳定性。

最后，该课题组人员演示了CDs@NaYF₄在3D打印、油性防伪图案和细胞成像中的应用。他们的工作可以为液相RTP材料的可控制备及其各种应用提供服务。

据了解，碳点在构建室温磷光（RTP）材料方面引起了越来越多的兴趣。然而，在CDs的溶液中，由于溶解氧和溶剂分子的强烈猝灭作用，获得高效稳定的磷光发射仍然是一个挑战。

附：英文原文

Title: Achieving Room-Temperature Phosphorescence in Solution Phase from Carbon Dots Confined in Nanocrystals

Author: Xiaoyan He, Weilan Huang, Yihao Zheng, Xiaokai Xu, Haopeng Wei, Ping Liang, Xianfeng Yang, Chaofan Hu, Xuejie Zhang, Bingfu Lei, Xingcai Zhang, Jianting Ye, Yingliang Liu, Jianle Zhuang

Issue&Volume: 2025-02-05

Abstract: Carbon dots (CDs) have attracted growing interest in the construction of room-temperature phosphorescent (RTP) materials. However, in the solution phase of CDs, it is still challenging to obtain efficient and stable phosphorescent emission due to the intense quenching effect by dissolved oxygen and solvent molecules. Herein, we report robust phosphorescence in the solution phase, achieved by encapsulating citrate-derived CDs into NaYF4 nanocrystals via a one-step method of high-temperature coprecipitation. Combined characterizations show that the triplet emission from CDs is related to the abundance of C=O in the CDs, the formation of ionic-bond networks around the CDs, and the spatial confinement and quenching inhibition effects of NaYF4 nanocrystals. Notably, the transition of CDs@NaYF4 from hydrophobicity to hydrophilicity can be easily achieved by simple surface modulation of NaYF4 nanocrystals, which allows the RTP of CDs to be maintained in either polar or nonpolar solvents. In addition, CDs@NaYF4 exhibits stable afterglow in different pH environments, suggesting its excellent stability. Finally, we demonstrated the application of CDs@NaYF4 in 3D printing, oily anti-counterfeiting patterns, and cell imaging. Our work can serve the controllable preparation of solution-phase RTP materials and their various applications.

DOI: 10.1002/anie.202423388

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202423388