基于荧光金属-有机框架的仿生结构色材料的构筑及性能研究

Aiming at the traditional fluorescent anti-counterfeit materials are easily to be deciphered and imitated, this project proposes to take the advantages of metal-organic frameworks (MOFs) bionic structural color materials in optics, further using bionics principles, and periodically arrange them in space to construct structural color films, and develop dual anti-counterfeiting systems that are easy to identify and difficult to counterfeit. We will design excellent luminescence MOFs nanomaterials on molecular level as the building blocks to construct fluorescent structural color films on different substrates. We aim to explore the assembly rule of MOFs, make optical adjustment from perspectives of both electron and photon level, study the transition mechanism of electrons as well as the propagation path of photons in MOFs structure, and elucidate the effect of the fine structure of MOFs on their fluorescence emission. Finally, we intend to create new anti-counterfeit materials with structural color and fluorescent through coordination and integration of the MOFs with fluorescence emission and the construction of structural color. We hope to provide new insights and experimental foundation for construction and application of new types of multiple anti-counterfeit materials through studying the nature as well as the essence relationship between materials structural color and fluorescence.

针对传统荧光防伪材料容易被破译以及仿冒等问题，本项目拟利用荧光金属-有机框架（MOFs）纳米材料在光学方面的优势，进一步借助仿生学原理，将其在空间上进行周期性排列构筑结构色薄膜，发展易于识别、难于伪造的双重防伪体系。为此，在分子水平上设计、合成具有优异发光性能的MOFs纳米材料，并以此为构建基元，在不同基底上构建荧光结构色薄膜。探索材料的组装规律，从电子和光子层面同时对结构色材料进行光学调控，研究电子在MOFs构建基元中的跃迁机理及光子在MOFs纳米阵列中的传播路径，揭示结构色材料精细结构对MOFs构建基元荧光发射的影响规律，通过研究材料结构色-荧光性能之间的内在本质关系，深刻认识此类材料的优势和局限性，为新型光学防伪材料的设计合成提供新的思路与方法以及在开发应用上提供理论和实验依据。

本项目通过选择不同有机配体与金属离子反应设计合成了一系列配位聚合物，测试并解析了它们的晶体结构，并利用红外、热重、元素分析、粉末衍射等对其进行了表征，并对部分配合物的催化、吸附、光学等性能进行了研究。在前期研究的基础上，筛选出部分具有优异发光性能的MOFs纳米材料，并以此为构建基元，采用溶剂挥发垂直沉降自组装法，得到了由荧光MOF纳米颗粒规则排列的条纹阵列。系统地研究了MOFs纳米颗粒尺寸形貌、悬浮液浓度、体系温度湿度、不同基底对MOFs基结构色薄膜带隙的影响。在项目实施过程中，还尝试了从光的各向异性角度出发，研究材料的偏振光特性，进一步从空间尺度实现了多重功能的结构色防伪材料。为定向构筑新型功能材料提供新的思路与方法。项目执行期间项目成员新获批国家自然科学基金青年项目2项，项目负责人作为主要参加者获河南省科技进步二等奖1项，河南省自然科学三等奖1项；在Adv. Opt. Mater, Rare Metals, Inorg.Chem., Cryst. Growth. Des., Front. Chem.等国内外期刊发表SCI收录论文14篇，培养硕士研究生2名。