红色固态荧光碳量子点的制备及在指纹检测中的应用

Preparation of red solid carbon quantum dots and its application in fingerprint detection

荧光碳量子点是一种新型的光致发光纳米材料,由于其具有稳定的发光性能、丰富的表面官能团、安全无毒、生物相容性好、成本低廉等优势,在潜指纹检测和识别领域有着极大的应用前景。潜指纹是指人的手指分泌物留在固体接触面上靠肉眼难以分辨的痕迹,需要借助物理或化学方法以有效地显现和提取。到目前为止,关于碳量子点显影潜指纹并与计算机技术结合精确识别指纹的研究鲜有报道。以邻苯二胺为前驱体,以草酸锌为修饰剂,采用一步溶剂热法成功合成了红色荧光碳量子点,将红色荧光碳量子点与聚乙烯吡咯烷酮混合,干燥研磨后制备出均匀分散、量子产率高达27%的红色固态荧光碳量子点,并成功应用于多种基底上潜指纹的增强检测。为了精确评价显影潜指纹与目标对照指纹之间的相似度,通过结构相似度算法进行相似度分析,锡纸上潜指纹的匹配度高达90.5%,表明红色固态荧光碳量子点结合数字处理程序能很好地显影和精确识别潜指纹,在刑事侦查领域具有极大的应用前景。

Fluorescent carbon quantum dots(CQDs)are a new type of photoluminescent nanomaterials.Due to their stable luminescent properties,abundant surface functional groups,safety,non-toxicity,good biocompatibility and low cost,they have great application prospects in the field of latent fingerprint detection and recognition.Latent fingerprints refer to the traces of human finger secretions left on the solid contact surfaces that are difficult to distinguish with the naked eyes,which require effective physical or chemical methods to effectively display and extract.So far,there are few reports on the development of latent fingerprints using CQDs and their precise identification in combination with computer technology.In this paper,red CQDs were successfully synthesized by one-step solvothermal method using o-phenylenediamine as the precursor and zinc oxalate as the modifier.The prepared red CQDs were mixed with polyvinylpyrrolidone,dried and ground to prepare red solid luminescent CQDs with uniform dispersion and quantum yield up to 27%,which were successfully applied to enhance the detection of latent fingerprints on various substrates.In order to accurately evaluate the similarity between the developed latent fingerprint and the target reference fingerprint,the structural similarity algorithm was used for similarity analysis.The matching degree of the latent fingerprint on the tin foil was as high as 90.5%,indicating that the combination of red solid fluorescent CQDs with digital processing programs can effectively develop and accurately identify latent fingerprints,which has great application prospect in the field of criminal investigation.