Preparation of Blue Light Carbon Dots Composite Fluorescent Powder and Its Application in Fingerprint Detection

以富含花青素的桑葚为碳源，通过水热法成功制备了氮掺杂蓝色荧光碳点(N-CDs)，并将其分别与淀粉、壳聚糖、纤维素等基质复合制备了蓝光复合荧光粉。通过TEM、FTIR、XPS、PL和UV-Vis对N-CDs的形貌、表面结构及光学性质进行了表征分析，结果表明，N-CDs表面富含羟基、氨基等亲水性官能团，具有优异的蓝光发射性能。淀粉基复合荧光粉在紫外光照射下也呈现明亮的蓝色，将其应用在指纹检测中时，能清晰呈现指纹的指突终点、起点等细微特征。本研究不仅提供了一种生物质自掺杂碳点的制备方法，还解决了固态荧光淬灭问题，为开发环保型指纹检测材料提供了参考。Nitrogen doped blue fluorescent carbon dots (N-CDs) were prepared by hydrothermal method using mulberries as carbon source, and blue light composite fluorescent powders were prepared by compounding them with starch, chitosan and cellulose. The morphology, surface structure and optical properties of N-CDs were characterized and analyzed by TEM, FTIR, XPS, PL and UV-Vis. The results show that the surface of N-CDs is rich in hydrophilic functional groups such as hydroxyl and amino groups, and has excellent blue light emission performance. Starch-based composite phosphors also present a bright blue color under ultraviolet light. When applied in fingerprint detection, they can clearly show the subtle features such as the end and beginning points of fingerprints. This study not only provides a preparation method for green preparation method for biomass self-doped carbon dots, but also solved the problem of solid-state fluorescence quenching, offering a reference for the development of environmentally friendly fingerprint detection materials.