螯合性模板剂导向介孔基复合材料的分子设计与可控制备

The crystal lattice defects of pure mesoporous silica are so less that it can not be used directly as catalyst. Other mesoporous materials such as transition metal oxides and sulfides also have some problems, for instance, poor thermal stability and pore structure is easy to collapse. Therefore, with the help of the variable valence of metal ions, doping the metal ions into the channels of silica efficiently and uniformly is the efficient way to improve the catalytic performance. This project intends to EDTA and citric acid as chelating structure unit, introduced different structures and chain length of the hydrophobic segment in one of its groups, and as the chelating template of mesoporous composite materials based on the detailed study of the composition of product, multi-tooth coordination effect, stable parameters, solution properties and micellization behavior, the object precursor was introduced into the channels of mesoporous directionally, and the it can be realized the synchronization of doping and synthesis for mesoporous materials effectively. The effect of the object introduced quantity, the structure, composition and properties of mesoporous against to the concentration of template agent, pH value of solution, the type of help structure directing agent, seasoning time and calcination condition are going to explore. The completement of this project can provide theoretic evidence for the choose and synthesis of chelating agent, it also gives us an new way which features orderly structure, good stability, efficient reactivity, small and well distribution of object metal (oxide), it plays a significant role in the production and application of mesoporous composites.

纯介孔二氧化硅的晶格缺陷少，难以作为催化剂直接使用，而过渡金属氧化物和硫化物等介孔材料尚存在热稳定性较差、孔结构容易坍塌等问题。因而利用金属离子存在的可变价态，将其有效、均匀地掺杂到介孔二氧化硅孔道中是提高其催化等性能的有效途径。本项目以乙二胺四乙酸和柠檬酸等为螯合性结构单元，在其一个基团上定量引入不同结构与链长的疏水链，在详细研究其组成、多齿配位作用、稳定参数、溶液性质及胶束化行为的基础上，作为合成介孔复合材料的螯合性模板，将金属客体前驱体“定向”引入至介孔孔道中，有效实现介孔复合材料的合成与掺杂同步；探索模板剂的浓度、溶液的pH值、助结构导向剂类型、陈化时间及煅烧条件等对客体引入量、介孔结构、组成与物性的影响。项目的完成可为螯合性模板剂的选择与合成提供理论依据，构建结构有序、稳定性好，客体纳米金属（氧化物）粒径均匀分布和反应活性高的新方法，对介孔复合材料的制备与应用具有重要的理论意义

纯介孔二氧化硅的晶格缺陷少，难以作为催化剂直接使用，而过渡金属氧化物和硫化物等介孔材料尚存在热稳定性较差、孔结构容易坍塌等问题。因而利用金属离子存在的可变价态，将其有效、均匀地掺杂到介孔二氧化硅孔道中是提高其催化等性能的有效途径。首先，我们详细研究了模板剂的组成、多齿配位作用、稳定参数、溶液性质及胶束化行为，以螯合型表面活性剂N-月桂酰基乙二胺三乙酸LED3A为模板剂，利用其与金属Co2+的配位作用，将其“定向”引入介孔孔道，一步法制备了Co3O4介孔SiO2复合体，实现介孔复合材料的合成与掺杂同步。并在此基础上，研究了模板剂的浓度、溶液的pH值、助结构导向剂类型、陈化时间和煅烧条件等对客体引入量、介孔结构、组成与物性的影响。本项目为螯合性模板剂的选择与合成提供理论依据，构建结构有序、稳定性好，客体纳米金属（氧化物）粒径均匀分布和反应活性高的新方法，对介孔复合材料的制备与应用具有重要的理论意义。