| Microporous zeolite materials with uniform and molecular-size pores have been widely used in many fields such as ion-exchange, adsorption and separation, and industrial catalysts. However, they cannot effectively deal with large molecules due to the limitation of the micropore size. Mesoporous molecular sieves show great potential applications and attract much attention because of their uniform and larger mesopores. However, when compared with microporous zeolite, mesoporous materials show poor hydrothermal stability and weaker catalytic activity, which seriously limit their extensive uses.With the great progress gained in the field of the mesoporous materials research, the synthesis of mesoporous materials is not limited in the alkaline media. Stuky et al have synthesized SBA-15 series materials in strong acid media. Such materials have more advantages than the materials (MCM-series materials) synthesized in alkaline media, such as the thicker mesoporous pore walls, the larger pores and the more ordered channels. However, the synthesis of heteroatoms contained SBA-15 is difficult, because the metals will only exist in the cationic form other than their corresponding oxo species in the strong acid media. Consequently they can not enter the silica framework by condensation with silicon species and therefore it is difficult to directly prepare heteroatom-containing mesoporous silicas under strong acidic media. As we all have known, pure silica materials cannot provide catalysis sites. Only the heteroatoms can provide them. Moreover, the heteroatoms introduced into the mesoporous walls can improve the hydrothermal stability of the materials.Generally, there are two kinds of methods for the incorporation of heteroatoms, "direct-synthesis" and "post-synthesis". For"direct-synthesis" method, the operation of it is relatively simple, however, the amount of the heteroatoms introduced into the mesoporous walls is little though there may be a large amount of the heteroatoms added in the initial gel. For "post-synthesis" method, the amount of heteroatoms introduced is larger, however, the operation is so complicated, sometimes glovebox is necessary because some metals are easy to oxygenate when they are exposed to water and oxygen. Once the oxygen is formed, it will jam the channels and limit their application. On the other hand, the procedure is easy to destroy the structure of the ordered mesoporous material.We find that heteroatoms can be effectively introduced into the framework of mesoporous silica by using "seed solution" as precursors. This is because heteroatom species have been fixed in the framework of the zeolite primary units when the seed solution is prepared and with the self-assembly of the zeolite primary units surrounding the surfactant, heteroatom species are directly introduced into the mesostructure. Here we synthesize mesoporous aluminosilicate MAS-7 and MAS-9 and titanosilicate MTS-9 by using Beta, ZSM-5 and TS-1zeolite seed solution as inorganic precursor respectively and triblock copolymer surfactant as template. MAS-7 and MAS-9 are proved containing the structure units of zeolite in their wall and they show greatly improved hydrothermal stability compared to conventional mesoporous materials. When treated in boiling water for 120 h, the decrease of their surface areas is less than 20% and the well-difined mesopore size distributions are maintained. Moreover, MAS-7 and MAS-9 show stronger acidity than conventional mesoporous aluminosilicates and better catalytic activity in cracking especially for bulky molecules. MTS-9 also possesses better hydrothermal stability than conventional mesoporous materials. In phenol hydroxylation and styrene epoxidation, MTS-9 shows activity and selectivity similar to those of TS-1. In 2,3,6-trimethylphenol hydroxylation, MTS-9 exhibits its special ability for bulky molecule reaction over TS-1 due to its larger pore. It has been proved by various spectra technology e.g. Uv-vis and Uv-Raman, etc that the heteroatoms introduced by "seed so...
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