洛阳师范大学马录芳团队报道了基于主-客体策略的光致变色金属-有机框架及不同紫外光衍生物用于有机胺传感和信息防伪。相关研究成果于2025年1月22日发表在国际顶尖学术期刊《德国应用化学》。

紫精衍生物在金属有机框架（MOFs）中的包封以构建主客体材料因其独特的空间排列和物理/化学性质而受到广泛讨论。

该文中，研究人员基于主客体策略，通过1,1,2,2-四（4-羧基苯基）乙烯（H4TCPE）配体和三种不同的紫精衍生物成功合成了三种新的光致变色MOFs（NWM-1-3）。值得注意的是，NWM-1-3在365nm紫外线照射下表现出从黄色到绿色的显著可逆光致变色变化。紫精中缺电子的N原子和富电子的羧酸盐氧之间的距离满足电子转移途径，因此在照射时发生电子转移（ET），产生分子间紫精自由基。NWM-1能够通过ET对不同的挥发性胺产生有色反应，并且肉眼可以识别。差分脉冲伏安法（DPV）分析和对比实验表明，主客体策略显著提高了紫精的电子接受能力，从而实现了优异的胺传感性能。NWM-2和3已经通过多种方法实现，如喷墨打印、指纹和用于防伪的二维码。

该项工作为设计高灵敏度光致变色材料和颜色可调发光材料提供了新的主客体策略，推动了组装光致变色物质的开发更接近商业化。

附：英文原文

Title: Photochromic Metal-organic Frameworks Based on Host-guest Strategy and Different Viologen Derivatives for Organic Amines Sensing and Information Anticounterfeiting

Author: Yi-Dan Li, Lu-Fang Ma, Guo-Ping Yang, Yao-Yu Wang

Issue&Volume: 2025-01-22

Abstract: The encapsulation of viologen derivatives in metal-organic frameworks (MOFs) to construct host-guest materials has been widely discussed owing to their distinctive spatial arrangement and physical/chemical properties. Herein, three new photochromic MOFs (NWM-1-3) have been successfully synthesized by 1,1,2,2-Tetra(4-carboxylphenyl)ethylene (H4TCPE) ligand as well as three different viologen derivatives based on host-guest strategy. Remarkably, NWM-1-3 exhibit a notable reversible photochromism change from yellow to green under 365 nm UV irradiation. The distance between the electron-deficient N atom in the viologens and the electron-rich carboxylate oxygens satisfies the electron transfer pathway, and thus electron transfer (ET) occurs upon irradiation, producing intermolecular viologen radicals. NWM-1 is able to produce colored responses to different volatile amines by ET and can be recognizable to the naked eye. Differential Pulse Voltammetry (DPV) analysis and comparative experiments have demonstrated that the host-guest strategy significantly enhances the electron-accepting ability of viologens, thereby achieving superior amine sensing performance. NWM-2 and 3 have been realized by multiple methods, such as inkjet printing, fingerprint, and QR codes for anti-counterfeiting. This work provides new host-guest strategy for designing highly sensitive photochromic materials and color-tunable luminescent materials, advancing the development of assembled photochromic materials closer to commercialization.

DOI: 10.1002/anie.202421744

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202421744