Cai Tingting, Zhao Yifan, Zhang Tingyu, Yang Yun
Department of Chemical and Material Engineering, Lyuliang University, Lyuliang, China.
Department of Resource and Mechanical Engineering, Lyuliang University, Lyuliang, China.
Mikrochim Acta. 2025 Jul 18;192(8):504. doi: 10.1007/s00604-025-07334-3.
Three kinds of N-doped carbon dots (CDs) were synthesized via the solvothermal method using orange juice, lemon juice, and banana leaves as biomass precursors. These CDs exhibited different fluorescence of blue, green, and red with the fluorescence quantum yield (FLQYs) of 16.2%, 14.5%, and 8.4%, respectively. The structure and composition analysis showed that B-CDs and G-CDs were nitrogen doped by urea with the content of about 4%, improving the fluorescence intensity significantly. Notably, the FL of R-CDs were composed of a blue FL emission and a red FL emission, which were inferred to be related to the CDs and chlorophyll-derived porphyrin. Three corresponding CD-based fluorescent inks were prepared by mixing with the thickening agent of glycerol. The application on handwriting, screen printing, and official seal indicated the multilevel UV/visible light dual-mode encryption potential. Furthermore, flexible sensing films were fabricated by incorporating CDs into polyvinyl alcohol (PVA) matrices. Remarkably, the CD-embedded films exhibited significantly enhanced electrical signal responses during mechanical sensing. This work not only provides a novel strategy for high-value utilization of biomass resources but also opens innovative pathways for developing intelligent anti-counterfeiting materials and flexible electronic devices.
采用水热法，以橙汁、柠檬汁和香蕉叶为生物质前驱体，合成了三种氮掺杂碳点（CDs）。这些碳点分别呈现出蓝色、绿色和红色的不同荧光，荧光量子产率（FLQYs）分别为16.2%、14.5%和8.4%。结构和成分分析表明，B-CDs和G-CDs是由尿素进行氮掺杂的，掺杂量约为4%，显著提高了荧光强度。值得注意的是，R-CDs的荧光由蓝色荧光发射和红色荧光发射组成，据推测这与碳点和叶绿素衍生的卟啉有关。通过与甘油增稠剂混合，制备了三种相应的基于碳点的荧光油墨。在手写、丝网印刷和公章方面的应用表明了其具有多级紫外/可见光双模式加密潜力。此外，通过将碳点掺入聚乙烯醇（PVA）基质中制备了柔性传感薄膜。值得注意的是，嵌入碳点的薄膜在机械传感过程中表现出显著增强的电信号响应。这项工作不仅为生物质资源的高价值利用提供了一种新策略，也为开发智能防伪材料和柔性电子器件开辟了创新途径。
