新型染料/金属有机框架复合材料的可控组装及其发光性能研究

Research on luminescent metal-organic frameworks (MOFs) has been a hot topic in the field of chemistry and materials science. Serving as host matrices, MOFs offer a unique platform to encapsulate organic fluorescent dyes, leading to novel and tunable luminescence behavior. However, the assembly process of the dyes in the pores of MOF materials is still difficult to effectively control, and the influence mechanisms of the luminescence properties have been scarcely reported. Aimed on these key scientific problems, a serial of porous MOFs with excellent ion-exchange ability will be designed and synthesized in this proposal, and then the organic dyes will be introduced into the channels as guest molecules through the ion exchange method to form the dye/MOF composites. The assembly and encapsulation of dyes into MOFs can be rationally tuned and controlled utilizing the strong ion force between the MOF and dye and the pore confinement effect. Through the implementation of this proposal, the relationship between luminescent properties and aggregate state, packed structure, and dipolar orientation of dye molecules will be discovered. In addition, the influence of the molecular interaction, electron transfer and energy transfer on luminescent properties will be investigated. Thus, the design theories and controllable assembly of dye/MOF composites with excellent luminescent properties will be established. It is believed that the results will further facilitate the exploration of such dye/MOF composites as new types of functional materials for applications in the fields of fluorescence sensing, optical information storage and light-emitting display.

发光金属－有机框架材料是当前化学和材料科学领域的一个热点课题，在其孔道中组装引入有机荧光染料为获得新的发光性能和实现发光性能调控提供了新的途径。然而，目前还难以有效控制染料客体在金属－有机框架材料孔道中的组装过程，对影响发光性能的各种因素和协同作用机制也缺乏深入研究。围绕这些关键科学问题，本项目将设计合成具有优良离子交换特性的多孔金属－有机框架材料，并通过离子交换方法在框架孔道内引入发光性能优良的有机染料组装染料/框架复合材料，利用框架材料与染料之间较强的离子作用力并结合框架孔道结构的调变来控制染料分子在框架材料中的组装与堆积过程，阐明染料分子的聚集形态和堆积结构与发光性能的构效关系，揭示框架材料中有机配体、金属中心与染料分子之间的相互作用、电子转移和能量传递过程对复合体系发光性能的影响和机理，获得一批发光性能优异的染料/框架复合材料，并探索在荧光传感、光信息存储和发光显示等领域的应用。

围绕金属-有机框架材料的结构设计与可控制备等关键问题，设计合成了一批新型金属-有机框架材料，实现了离子密度可调、作用位点多样的离子型金属-有机框架材料的可控制备，完善了金属-有机框架材料的设计理论，建立了具有预期结构的金属-有机框架材料的可控组装方法。研究了有机染料在金属-有机框架材料孔道中的进入、分布与排列堆积过程，深入研究揭示了孔道结构和孔径大小与有机染料分子定向排列的关联与机理，阐明了框架材料与染料客体之间的相互作用对染料分子堆积排列的影响和控制规律，研究了染料分子的堆积结构和聚集形态与发光性能之间的关联关系，探索了染料/框架复合体系在荧光传感、发光显示、信息存储和非线性光学等领域的应用研究，为金属-有机框架材料实现新的光子功能应用提供了设计思路和组装方法。