无机孔材料的可控合成与结构性质研究

Inorganic porous materials have attracted enormous interest due to their wide applications in catalysis, separation and ion exchange. One of the difficulties which hint their even wider applications is that the synthesis strategies of inorganic porous materials are not well developed. In the traditional synthesis routes, new inorganic porous materials are normal synthesized after a large amount of trials and errors and the experience of the success in synthesizing one cannot be easily transferred to the synthesis of the others. Inspired by the synthesis of metal-organic frameworks, we will develop a new synthesis route for inorganic porous materials. Normally, this type of materials are synthesized by using single ion polyhedra as building units, and due to the flexibility of the ion polyhedra, it is very difficult to predict what will be obtained. Instead, we will use big clusters as building units in this project. According to the functional groups and their distribution in different clusters, we will choose the suitable metal polyhedra as linkers to assemble them into three-dimensional frameworks. Since the big clusters have fixed internal structure and functional groups, this synthesis route is more controllable than the traditional synthesis methods. In the project, we will also develop new structure determination methods to solve structures of the obtained porous materials which is normally in a powder form with huge unit cell dimensions. We will also use various techniques to study the crystal growth mechanism by tracking the formation/assembly of the cluster, growth/dissolving of the porous material crystal, which will provide important knowledge for the new designed synthesis.

无机孔材料由于其在催化，分离，离子交换等方面广泛的工业应用，一直是各个国家的研究热点。但其应用的最大的障碍之一是其合成方法不具有普遍性，一般一个新型无机孔材料的发现需要大量的实验尝试，而这些尝试的经验往往不能轻易的移植到别的体系中。由金属有机骨架材料的合成方法获得启发，本项目将集中发展新的无机孔材料的合成方法。传统的无机孔材料合成一般以单个的离子配位多面体为结构单元，由于其多变性，一般很难预测产物的结构，因此本项目将使用大的离子簇作为结构单元。针对离子簇具有的官能团及其官能团分布的不同，通过选择合适的简单金属多面体将它们连接成三维骨架，由于离子簇结构的确定性，这样的合成思路更具有可控性。课题中将发展新的结构确定方法以解决粉末状态下具有超大单胞的孔材料结构，还将通过不同的技术追踪离子簇的形成和聚集，晶体的生长和溶解等过程，从而为更理性的设计新的合成提供基础。