| "No materials, no progress"means that science of materials is very important for the modern science and technology and also for the development of the society. The research of new materials with novel structures and outstanding properties is also a hot research subject for materials scientists. For all of the material researchers, tremendous efforts have been made in developing porous materials for their potential applications as advanced catalysts, adsorbents, sensors, optical waveguides, dielectrics, and bioreactors. The main works of my thesis are devoted to the design, syntheses, and characterization of porous materials with single-sized and/or hierarchical pores and their significant properties.As we know, porous materials contain normal materials with the unique pores of single-size and hierarchical porous materials. Unique porous materials with single pore sizes, such as zeolite A, X, ZSM-5 et al, have been researched for about two hundreds years and have been applied to manufacturing production in industry. Although the mesoporous materials which are also one of the important unique porous materials with single pore sizes, have been investigated for only 20 years, this kind of materials have been attracted much attentions due to their novel features, such as high regularity and unique tunable nanometer pore sizes, high surface areas, large pore volumse, and tailorable surface chemical properties. The main contents of mesoporous molecular sieves range from synthesis, morphology, modification, and assembly, and great progress have been made in the field of catalysis, adsorption, separation, purification, optics, preparation of nano-materials et al. Now, a lot of mesoporous materials with different pore structures have been prepared, but the methods to synthesize different meso-structures by controlling the formation of meso-structure phases are not fully-fledged and difficult to be achieved. The current situation seriously limits the application of mesoporous materials in industry. Furthermore, the pore sizes of the current mesoporous materials are a limitation for their application to bio-chemistry, especially for bio-molecules with macro-size. Thus, mesoporous materials with ultra-large pores are always greatly expected. Some strategies have been reported to obtain large-pore materials, but it is still a big challenge to develop a facile method to control the pore sizes of the porous materials between 20nm and 50nm. In the first part of my thesis, due to the problems existed that are mentioned above for mesoporous materials, we obtained mesoporous silicate with different pore structure by controlling of mesostructure phases with a very simple method, and by controlling the pore size method, we synthesized a series of mesoporous silica with ultra-large pores.With the development of society and the investigation of the porous materials, the materials with only one pore-size could just acted as an appointed role in the multi-applications due to the unique pore-size, which hinders the application in hierarchical catalysis. In the second part of the thesis, great efforts were made on the design and syntheses of hierarchically porous zeolite catalysts. We have firstly succeeded to obtain different kinds of hierarchically porous catalysts with micro-meso-macro pores system constructed by different.The thesis contains two parts. The first part is the design and synthesis of porous silica with different pore structure and ultra-large pore system respectively(Chapter two and Chapter three). The second part is the design and syntheses of hierarchical porous matetials constructed by different zeolites (Chapter four, Chapter five and Chapter six).For the first part, Chapter one is the control and synthesis of mesoporous silica with Ia3d structure using P123 as template under HNO3 condition. Interestingly, we found that only by changing the quantity of acid added in the starting gel, the meso-phases of the obtained sample could change from 2D hexagonal phase to 3D cubic phase. Then we got the mesoporous silica with different meso-structures. XRD and TEM were used for characterizing the process of the mesostructure phase changes. Furthermore, by change the quantity of the salt added in the starting gel, the mesostructure phases of our samples could also be controlled. In chapter two, we present a facile, reproducible, high-yield synthesis of mesoporous silica biomaterials with uniform and tunable pores of 20 to 40 nm in a neutral pH system of Brij-Ester-APS-H2O-SiO2 (Brij-n polyethylene alkyl ether, APS, 3-aminopropyl- trimethoxy silane) at room temperature. Here, we find the mesoporous materials with ultra-large pore can also be obtained when using small organic molecule (ethyl acetate) as additive. By using different templates and additives, mesoporous silica with ultra-large pore size, 20nm, 33nm, and 40nm respectively, were synthesized. We have explored the potential applications of our new materials in selective adsorption of biomacromolecules by the mesopore space limitation. The products have shown efficient performance of size selective adsorption of biomacromolecules, demonstrating great potentials in biomacromolecular separation.The second part of the thesis is the design and syntheses of hierarchically porous materials constructed by zeolites. In this part, we design a novel system using glycerin as medium, to make a transformation from the amorphous nanoparticles of the meso-macro hierarchically porous materials to crystalline zeolite nanoparticles by a transfer crystallization process. The transfer crystallization process has been investigated. Interestingly, the micro-meso-macro hierarchical porous materials composed of zeolites are synthesized for the first time.Micro-meso-macro hierarchically porous material constructed by Beta zeolite was synthesized in Chapter four. By the transfer crystallization process, we have success to transfer the amorphous nanoparticles of meso-macro hierarchical porous aluminosilicates to crystalline Beta zeolite. In chapter five, we design and synthesis of micro-meso-macro hierarchically porous constructed by TS-1 zeolite. The strategy is similar as the synthesis of micro-meso-macro hierarchical porous Beta. Moreover, micro-meso-macro hierarchically porous constructed by TS-1 zeolite with twin crystal structure and single crystal structure respectively were obtained by change the quantity of zeolite seed solution. The last chapter describes the design and synthesis of micro-meso-macro hierarchical porous composed of Zr-Silicalite-1. Using the similar strategy, it is the first time we get the hierarchically porous with micro-meso-macro pore structure constructed by Zr-Silicalite-1.
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