| Mesoporous and zeolite molecular sieve materials are currently under intense investigation with respect to their utilities as industrial catalysts, adsorbents, environmental protection, drug carriers, optics, electrode materials and host-guest chemistry. As a catalyst carrier, the pore size of mesoporous material is too large and the pore size of zeolite is too small to show shape-and size-selective properties in some special catalyzed reactions. Therefore, the synthesis of supermicroporous materials with pore diameters falling between the upper limit for zeolites and the lower end of the mesopore size range (from 1.0 to 2.0 nm) is an interesting topic in the fields of separation and catalysis. It is expected to have the potential selectivity of size and shape for those organic molecules in the fields of separation and catalysis. The achievements made in this thesis are summarized as follows:1st. Highly ordered supermicroporous silica was synthesized using short chains cationic trimeric surfactant C10-2-10-2-10 as the structure-directing agent and tetraethyl orthosilicate as the precursor. The data showed that the pore structure of the supermicroporous materials belonged to the two-dimensional hexagonal structure (space group 2D-p6mm) with a pore size 1.8 nm. The high-quality supermicroporous silica was formed at a low molar ratio of C10-2-10-2-10 to tetraethyl orthosilicate (0.16:1), which indicated that the self-assembly ability of C10-2-10-2-10 was stronger than that of corresponding monovalent surfactant (Decylhexadecyl trimethylammonium bromide). With the increase of hydrothermal temperature, the ordering of the supermicroporous structure increased first then decreased, at the same time the pore size was enlarged.2nd. The methods of calculating surface area and pore size of supermicroporous materials were strictly compared. PSDs were calculated from nitrogen adsorption data using BJH method (DBJHads) and geometrical models (Dd). According to the previous method of calculating pore size, which is based on the length of the alkyl chain of the trimeric surfactant C10-2-10-2-10,DBJHads is reasonable and close to the value obtained by HRTEM (1.8 nm), if the framework shrinkage of supermicroporous silica caused by calcination is considered. Dd can overestimate the pore size due to the use of the bulk silica density in calculating the pore size. The surface area was found to be in the range of 910-1,135 m2 g-1 by the as plot method.3rd. Highly ordered two-dimensional hexagonal (space group 2D-p6mm) supermicroporous aluminosilicates materials were synthesized with high aluminum contant (atomic Si/Al ratio between 2 and 9.5) via direct mixed-gel synthesis. These materials synthesized with sodium aluminate as the sources of aluminum and short-chain cationic trimeric surfactant C10-2-10-2-10 as structure-directing agent have uniform pore sizes being in the range of supermicroporous (1.16-1.91 nm). With the increase of hydrothermal temperature, the ordering of the supermicroporous structure increased, at the same time the pore size was enlarged.27A1 MAS NMR shows that both tetrahedral and octahedral coordinate aluminum are present in the calcined and protonic products. The aluminosilicate supermicroporous materials show Br(?)nsted and Lewis sites as confirmed by the DRIFT spectroscopy of chemisorbed pyridine and have high acid content in the range of 0.75～1.07 mmol H+/g.4th. Highly ordered two-dimensional hexagonal (space group 2D-p6mm) supermicroporous aluminosilicates materials have been successfully synthesized via direct mixed-gel synthesis with Gemini surfactant C12-412as structure-directing agent. The obtained samples with high aluminum contant (atomic Si/Al ratio between 2 and 9.5) have uniform pore sizes being in the range of supermicroporous (1.18-1.90 nm). Increasing hydrothermal temperature can improve the ordering of the supermicroporous structure.
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