稀土上转换发光纳米材料的防伪安全应用

Anticounterfeiting and Security Applications of Rare-Earth Upconversion Nanophosphors

与有机荧光染料、量子点等传统发光材料相比,稀土上转换发光纳米材料(UCNPs)具有反斯托克斯位移大、发光谱带多且狭窄、荧光寿命长、光化稳定性高、无光闪烁和光漂白等独特优势,将其与图形编码、防伪印刷技术结合可获得难以仿冒的隐形荧光图案,这已经成为防伪安全领域的应用研究热点。本文首先介绍了UCNPs的上转换发光机理及其合成方法,然后阐述近年来UCNPs在防伪安全领域的研究现状,归纳总结出上转换防伪安全图案的四种形式(NIR单波长激发、NIR双波长激发、NIR/UV双波长激发以及三波长激发)。最后,本文指出UCNPs应用于防伪安全领域所面临的问题与挑战,并对未来的发展方向进行了展望。

Compared with the traditional luminescent materials such as organic dyes and quantum dots,rareearth upconversion nanophosphors(UCNPs)have the unique advantages of large anti-Stokes shift,shaper and multicolor emission bands,long fluorescence life,high photostability and chemical stability,no photoblinking and photobleaching.The combination of UCNPs,graphical coding and anticounterfeiting printing technologies enables the formulation of invisible fluorescent patterns that are difficult to counterfeit.This has become a research hotspot in the field of anticounterfeiting and security.In this paper,the upconversion mechanism and synthetic methods of UCNPs are first introduced.Afterwards,the research status of UCNPs in the field of anticounterfeiting and security is elaborated,and four forms of upconversion anticounterfeiting and security patterns are summarized(i.e.NIR single-wavelength excitation,NIR dual-wavelength excitation,NIR/UV dualwavelength excitation and three-wavelength excitation).Finally,the problems and challenges that UCNPs are facing in the field of anticounterfeiting and security,and future development directions are also proposed.