Zhang Jiawei, Wang Zhijun, Huo Xiaoxue, Wang Yu, Yang Zhiping, Wang Dawei, Zhao Jinxin, Li Panlai
National-Local Joint Engineering Laboratory of New Energy Photoelectric Devices, Hebei Key Laboratory of Optic-electronic Information and Materials, College of Physics Science & Technology, Hebei University, Baoding 071002, China.
Hebei Key Laboratory of Semiconductor Lighting and Display Critical Materials, Baoding 071000, China.
Dalton Trans. 2022 Aug 16;51(32):12137-12146. doi: 10.1039/d2dt01617f.
Fluorescent materials have gradually become a hot spot in the field of anti-counterfeiting. Multifunctional phosphors used in anti-counterfeiting designs still have the problems of disordered reading sequences, difficulty in detection, and easy forging. To resolve these problems, we propose a new flexible dual-mode anti-counterfeiting design using a series of phosphors CaAlGeO:Cr (CAG) with deep red persistent luminescence peaking at 722 nm. By adjusting the doping concentration of Cr from 2% to 6%, deep red persistent luminescence with different afterglow intensities and durations can be achieved. By performing a series of thermoluminescence (TL) experiments under different conditions, the defects in materials were comprehensively and systematically analyzed. The defects contributed to the deep and shallow traps; this led to an obvious improvement in its long persistent luminescence (LPL). Such a dual-mode system with flexibility and simplicity properties is a good choice not only for anti-counterfeiting, but also for multi-layer information encryption, and a series of demo experiments based on the digital tube, Moss code, QR code, bar-code, school celebration pattern, and love letter information encryption design were implemented. Their dynamic anti-counterfeiting applications have been demonstrated, which provides a new way to rationally design multi-functional luminescent materials.
荧光材料逐渐成为防伪领域的一个热点。用于防伪设计的多功能磷光体仍然存在读取顺序混乱、检测困难和易于伪造等问题。为了解决这些问题，我们提出了一种新的柔性双模式防伪设计，使用一系列在722 nm处具有深红色持续发光峰值的磷光体CaAlGeO:Cr（CAG）。通过将Cr的掺杂浓度从2%调整到6%，可以实现具有不同余辉强度和持续时间的深红色持续发光。通过在不同条件下进行一系列热释光（TL）实验，对材料中的缺陷进行了全面系统地分析。这些缺陷导致了深浅陷阱的形成；这使其长余辉发光（LPL）得到了明显改善。这种具有灵活性和简易性的双模式系统不仅是防伪的良好选择，也是多层信息加密的良好选择，并且基于数码管、摩尔斯电码、二维码、条形码、校庆图案和情书信息加密设计进行了一系列演示实验。它们的动态防伪应用已经得到了证明，这为合理设计多功能发光材料提供了一种新方法。
