多功能金属铟有机框架材料的合成及其性能研究

As one new class of inorganic-organic hybrid materials, metal-organic frameworks (MOFs) are hydrothermally or solvothermally obtained from the self-assembly of metal ions or metallic clusters and organic linkers. Owing to extra large specific surface areas and porosity, and tunable pore environments, these porous coordination polymers are of great potentials to many applications, such as gas storage, selective sorption and separation, chemical sensing, drug delivery and release, host-guest recognition etc. Under the direction of the idea of superamolecule self-assembly, this project is mainly focused on the exploration and development of novel main group metallic indium-based organic frameworks, compared to conventional metal-organic materials based on transition metals or lanthanide metals. As usually, these indium-organic frameworks (InOFs) are structurally stable and composed of discrete microporous, mesoporous or even macroporous cages and/or 1-dimensional nano-sized channels. According to our previous preliminary research on InOF system, what we are going to do in this project are listed as follows: 1, owing to three kinds of typical indium-based secondary building blocks, namely, [In(CO2)4], In(OH)(CO2)2] and [In3O(CO2)6]，we plan to prepare highly porous and functionalized InOF materials; 2, meanwhile, we are now developing new method for the synthesis of new InOF materials by using the ligand-oriented Bifunctional Method. Case one: for aromatic N-containing ligands, COO--affinitive In(III) cations only bind to carboxylate groups while the N-affinitive metallic counterparts only to N-centers; Case two: for pure multicarboxylic ligands, In(III) cations connect to one part of carboxylate groups, and the other COO--affinitive metallic components connect to the remaining carboxylate groups. It has been confirmed to be valid to synthesize intriguing heterometallic structures that essentially derive from different affinity between various metallic ions and N/O-donor centers; 3, last but not least, we also try to study the mutual interaction between the host framework and gas molecules and/or small guest molecules and to study the multifunction of heterometallic InOF materials as well, including gas sorption, luminescence and magnetism and so on. Furthermore, InOF structures and measurements have been fully characterized by single-crystal X-ray diffraction, X-ray powder diffraction, infrared spectroscopy, elemental analysis, thermo-gravimetric analysis, and single component gas sorption experiment. In summary, this project wishes to provide theoretical and experimental support for developing new InOF materials for practical applications. This project is going to publish 4~6 papers and 1 patent.

金属有机框架化合物（MOFs）是由无机金属结点与有机配体自组装而成的一类新型杂化材料,在气体吸附和分离领域有着广泛应用。而基于三价主族金属铟离子的、有着稳定结构的金属铟有机框架化合物（InOFs）是研究主客体相互作用的理想平台，但是因其较强的亲氧性、极少的配位方式得到较少的关注。基于我们前期对InOFs体系的研究基础，本项目拟从以下三个方面进行研究：1、利用三种典型铟为基的次级构筑单元，来构筑官能团修饰的多孔InOFs材料；2、利用配体导向的“双功能方法”，加入竞争性金属组分或非竞争性金属组分来构筑多功能的异金属InOFs材料；3、研究框架与功能气体分子、客体小分子之间的相互作用极其作用机理，同时研究异金属InOFs材料的多功能性，包括吸附、荧光、磁性等性能。本项目有助于进一步揭示InOFs材料的合成规律，阐明结构与性能之间的关系，并为开拓新型多功能MOFs材料及其相关应用打下坚实的基础。

主族三价金属铟离子基稳定结构的金属铟有机框架化合物（InOFs）是研究主客体相互作用的理想平台，但因其较强的亲氧性、极少的配位模式得到较少的关注。本项目以我们前期对InOFs体系的研究基础，拟从以下三个方面进行研究：1、利用三种典型铟为基的次级构筑单元来构筑官能团修饰的多孔InOFs材料；2、利用配体导向的“双功能方法”，加入竞争性金属组分或非竞争性金属组分来构筑多功能的异金属InOFs材料；3、研究特定框架与功能气体分子、客体小分子之间的相互作用及其机理，同时研究异金属InOFs材料的多功能性，包括吸附、荧光、磁性等性能。我们发现了羟基或吡啶基团修饰的金属铟有机型框架化合物有较高的二氧化碳分子吸附能力，阐明了主客体分子间相互作用机制。具体来讲，我们发现二氧化碳分子O=C=O通过与顺式构型的羟基cis-μ2-OH配位，形成了一个端基end-on模式O=C=O...HO，该部分基团通过附近苯环上的氢键来共同起到稳定框架的作用。同时我们也发现，MOF-1系列中（M=Al, Ga, In）的AlOF-1与二氧化碳是具有最强的结合能。另外我们也合成一例新型的三维多孔InOF-15，它是一个稳定、刚性的金属有机框架化合物，它拥有路易斯碱的吡啶氮位点，同时也含有三核In3O端基配位的甲醇分子去除掉后的金属开放位点。两种位点协同作用导致了较高的IAST选择性吸附。综上，本项目有助于进一步揭示InOFs材料的合成规律，阐明结构与性能之间的关系，并为开拓新型多功能MOFs材料及其相关应用打下坚实的基础。