摘要
解决静态光学防伪材料信号显示单一、且极易被解密的问题，本文提出一种基于Cs₂ZrCl₆:20%Tb量子点与光致变色分子TINS的光控能量转移体系，通过紫外光调控实现动态荧光防伪。通过热注射法合成Cs₂ZrCl₆量子点，系统研究Tb3+在Cs₂ZrCl₆量子点中的掺杂浓度，确定20%为最佳掺杂比例。此时荧光强度达到最高，荧光量子产率达8.35%。进一步将Cs₂ZrCl₆:20%Tb量子点与TINS分子复合制备光响应荧光墨水，验证二者之间高效的能量转移过程，经过5次循环实验荧光强度无明显衰减。利用荧光墨水在特定紫外光激发下实现信号可逆切换的特点，设计动态光学编码。本工作的创新在于构建了一种具有高稳定性和良好可逆性的光控荧光防伪体系，为动态信息加密与高级防伪技术提供了新材料与新思路，显著提升了光学加密的安全等级与实用潜力。
关键词： 无铅钙钛矿量子点；能量转移；离子掺杂；光学防伪
Abstract
To address the issues of single signal display and easy decryption of static optical anti-counterfeiting materials, this paper proposes a light-controlled energy transfer system based on Cs2ZrCl6:20%Tb quantum dots and photochromic molecules TINS, achieving dynamic fluorescence anti-counterfeiting through ultraviolet light regulation. Cs2ZrCl6 quantum dots were synthesized by hot injection method. The doping concentration of Tb3+ in Cs2ZrCl6 quantum dots was systematically studied, and 20% was determined as the optimal doping ratio. At this point, the fluorescence intensity reaches its peak, and the fluorescence quantum yield reaches 8.35%. The photoresponsive fluorescent ink was further prepared by combining Cs2ZrCl6:20%Tb quantum dots with TINS molecules to verify the efficient energy transfer process between them. After five cycles of experiments, there was no significant attenuation of fluorescence intensity. Dynamic optical coding is designed by taking advantage of the feature that fluorescent ink can achieve reversible signal switching under specific ultraviolet light excitation. The innovation of this work lies in the construction of a light-controlled fluorescent anti-counterfeiting system with high stability and good reversibility, providing new materials and new ideas for dynamic information encryption and advanced anti-counterfeiting technology, and significantly enhancing the security level and practical potential of optical encryption.
Key words： Lead-free perovskite quantum dots; Energy transfer; Ion doping; Optical anti-counterfeiting
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