| Mesoporous SiO2 have unique structure such as extremely high surface area,narrow poer size distribution and large adjustable pore sizes(2-50nm), these have made such materials the focus of great interesting. They might be applied in various fields especially as adsoprtion and separation, ion exchange, catalysis, molecular host, optoelectronic and so on.In this paper, different surfactants were used to synthesis mesoporous silica and the adsorption properties of mesoporous silica after modefied by organic silane (KH550) were investigated. The formation mechanism of the mesoporous MOx-SiO2 composites was studied. This thesis includes the following sections:In the first part, mesoporous silica was prepared by hydrothermal method using the mixed anion-cationic surfactants as template. The structures of samples were influenced by the reaction conditions including amount of acid (pH of the solution), the mass ratio of alcohol/water and the calcination temperature. The experimental results showed that anion-cationic surfactants could also be used to get mesoporous silica materials with ordered pore structure. The samples with narrow pore distribution and a higher surface area could be synthesized under reaction conditions: t= 40℃, pH= 4.0, m(CH3CH2OH)/m(H2O)=3:1.Then mesoporous silica after calcined or ethanol extraction was modified by organic amino-silane. These products were characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, thermogravimetric analysis, nitrogen adsorption-desorption methods and so on. Adsorbability of modified samples on copper ions in the aqueous solution was studied. The results showed that the modified samples prepared from extracted SiO2 showed a better adsorbability. When the grafting rate was 7.8%, the adsorbability was the best. When the amount of surface modifier was increased too much, amino-alkyl chains of organic silane associated might block the pores of mesoporous SiO2, so that the adsorption capacity of the mesoporous materials greatly reduced.In the second part, CuO/SiO2 mesoporous materials or MnOx/SiO2 were prepared by one-pot hydrothermal method under different pH values, using tri-block copolymer (P123) as template agent and tetraethyl orthosilicate (TEOS) as silica source. The samples were characterized by N2 adsorption isotherm-desorption, X-ray diffraction (XRD), Fourier transform infrared (FT-IR), high resolution transmission electron microscopy (HRTEM) and inductively coupled plasma emission spectroscopy (ICP-AES). The results showed that:CuO/SiO2 synthesized in the case of pH<1.0 showed bimodal-mesoporous structure calculated from the desorption branch. When the pH value was gradually becoming higher(pH=1.5-4.0), CuO/SiO2 changed into single-mesoporous structure and pore diameter became larger. But the pore blocking existed when pH= 1.5-2.0. The bimodal-mesoporous structure of Mn loaded samples could be seen at pH values of 0.5 to 2.0. But the ink bottle type pore structure was appeared until pH=4.0 which was different from CuO/SiO2. The experiment results showed that the composites with different pore structures could be obtained by adjusting the pH values of the solution and the addition of different ions.
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