雪莲果皮衍生多模式碳量子点的制备及其防伪应用

以生物质废弃物雪莲果皮为碳源，乙二胺为氮源，采用一步水热法制备蓝色荧光氮掺杂碳量子点(N-CQDs)，并探索其在防伪中的应用。实验结果表明：N-CQDs为球形形貌，平均粒径约为1.88 nm；N-CQDs具有类石墨烯结构，表面富含氨基、羧基等官能团；N-CQDs的荧光对Fe³⁺及pH值具有响应性。以PAA为基质，将N-CQDs制备成丝网油墨，印制的图案在自然光下隐形，在紫外光下显示出蓝色荧光图案，移除紫外光后，呈现绿色磷光图案。此外，在图案上喷涂Fe³⁺溶液或碱液，其荧光被明显淬灭。基于响应性荧光碳量子点的防伪图案可实现静态、动态两种模式的信息存储，信息安全性与防伪等级更高。

Preparation of Snowdrop Peel-Derived Multimodal Carbon Quantum Dots and Its Anti-Counterfeiting Applications

Blue fluorescent nitrogen-doped carbon quantum dots (N-CQDs) were prepared by one-step hydrothermal method using biomass waste snowdrop peel as the carbon source and ethylenediamine as the nitrogen source, with their application in anti-counterfeiting explored. The results showed that N-CQDs were spherical in shape with a particle size of about 1.88 nm, and had a graphene-like structure with amino and carboxyl groups on the surface. The fluorescence of the N-CQDs was responsive to Fe3+ and pH value. PAA was used as a substrate to prepare N-CQDs into screen inks, and the printed patterns were invisible under natural light, showing blue fluorescent patterns under UV light, and showing green phosphorescent patterns when UV light was removed. In addition, the fluorescence luminescence was significantly quenched by spraying Fe3+ solution or alkali solution on the pattern. This anti-counterfeiting pattern based on responsive fluorescent carbon quantum dots can achieve two modes of information storage: static and dynamic, which can provide higher information security and anti-counterfeiting level.