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Porous material in accordance with the definition of the International Union of Pure and Applied Chemistry (IUPAC), the aperture in the material between the 2 ~ 50nm called the mesoporous material, less than 2nm called microporous material. The materials generally ultramicropore refers to a pore size between the microporous and mesoporous critical interval, i.e. within the porous material in the range of 1.0-2.0nm, and its synthesis, material properties similar to the mesoporous material. Preparation of ordered mesoporous materials is mainly based on the self-assembly of the surfactant system as a template to complete by the sol - gel chemistry. Ordered mesoporous materials having the following characteristics: (1) having a regular pore structure; (2) of the narrow pore size distribution, and can be adjusted between 2-50nm; (3) The large surface area; (4) having good thermal Stability and hydrothermal stability; (5) of the particles have a colorful appearance. Therefore, ordered mesoporous materials in the petrochemical, biocatalysis, adsorption separation, photocatalysis, environmental protection, pharmaceutical carriers, photoluminescence materials, electrode materials and host-guest chemistry exists an attractive prospect, caused by physical, chemical great concern and materials science and other fields to become one of the hot spots of interdisciplinary research. In this paper, a novel surfactant-Gemini surfactant (12-4-12 · 2Br - ,12-6-12 · 2Br - ) and imidazole-based ionic liquids (1 - alkyl-3 - methyl - imidazolium such as IL8, IL12, IL14, IL16) as template, successfully prepared high order, specific surface area, great ultramicropore mesoporous silica; In addition, it is also prepared superhydrophobic inorganic - organic hybrid mesoporous silica preliminary modified mesoporous silica. Samples using small-angle X-ray diffraction, N 2 adsorption - desorption, high-resolution transmission electron microscopy techniques, characterization. Studied the different structure of the surface active agent, the surface active agent with a silicon source, the proportion of the pore structure of the mesoporous materials, the specific surface area, pore size distribution, the influence of the pore volume and other properties. This is the first to contain longer join groups Gemini (Structure as the [C 12 H 25 N (CH 3 ) 2 - (CH 2 ) s -N (CH 3 ) 2 C 12 the H 25 ] · 2Br - s = 4 or 6, recorded as 12-4 -12 · 2Br - ,12-6-12 · 2Br - ) surfactant micelles as a template synthesis the the pore structure ultramicropore silica material. When the proportion of the surfactant with the silicon source is between 0.16:1 to 0.33:1, the synthesized product as well ordered hexagonal phase MCM-41 structure. When the synthesis of porous silica as the template 12-4-12 · 2Br - N 2 adsorption isotherms - desorption experiment results show that: type type Ⅳ samples with a high degree of order is the most probable pore size of about 1.67nm, BET surface area up to 1242m 2 / g. Nitrogen adsorption and high-resolution transmission electron microscopy results consistently demonstrate that the sample aperture around 1.7nm, belonging to the areas ultramicropore; 12-6-12 · 2Br - for template agent synthesis of porous silica N 2 adsorption isotherms - desorption experiment results show that: type Ⅳ type, degree of order higher sample the most probable pore size of about 1.4nm, BET surface area of ??up to 1178 m < sup> 2 / g. HRTEM (1.3-1.5nm) is basically the same, the description of the resulting material for ultrafine pore silica. The same time, we found that the orderliness of the pore structure, specific surface area increased with the increase in the proportion of surfactant and sodium silicate, when the proportion of surfactant and a silicon source is greater than 0.08:1 can be obtained high quality ultrafine mesoporous silica. Appears the type Ⅳ between isothermal line in the gas adsorption - desorption curve. At a relative pressure P / P 0 = 0.5-1 at H 1 -type hysteresis loop, which is caused by the capillary condensation of the voids between the material particles. Article also take advantage of the new alkyl imidazolium ionic liquid as a template, sodium metasilicate as the silicon source, the successful preparation of highly ordered hexagonal mesoporous materials, and the use of small-angle X-ray diffraction, N 2 adsorption - desorption, HRTEM characterized synthetic materials, research results show that when the silicon source with the ionic liquid (IL16) ratio of 2:1, four very high levels in the small-angle range of the XRD the diffraction peak (corresponding to the crystal plane of the hexagonal structure 100,110,200,210 four), specific surface area of ??up to 1727m 2 / g, pore size distribution is relatively uniform, with the ratio of silicon source, and ionic liquids (IL16) changes sample aperture between 2.03-2.88. Focuses on the pore structure of mesoporous materials change surfactant, changing the pH and a change in the ratio of surface active agent with a silicon source, a specific surface area, pore size distribution, pore volume and other properties of the impact, the study found that the self-assembly of ionic liquids The ability to order: IL8 IL12 - template agent, dodecyl trimethoxy silicon and TEOS common source of silicon, the successful synthesis of inorganic - organic hybrid mesoporous silica, the contact angle of about 152 ° superhydrophobic, but ordered pore structure deteriorate. Meanwhile, the experiments also showed that over reducing the silicone content in the product of the hydrophobicity of the product is significantly weakened.
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