TAILIEUCHUNG - Synthesis and characterization of MCM-41 containing CeO2
The characteristics of all samples were investigated by ThermoGravimetric - Differential Thermal Analysis (TG-DTA), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Energy-Dispersive X-ray spectrometry (EDX) and nitrogen adsorption-desorption isotherms. The results indicated that: particles are sphere, uniform and pore size is about 50 nm; the pore systems are hexagonal structure, ordered arrangement; the samples have high surface area (> 600 m2 /g) with narrow pore size distribution curve. Results of EDX showed that the SiO2/CeO2 molar ratios of samples were very similar to the molar ratios in gel. | Journal of Chemistry,Vol. 45 (2), P. 245 - 249, 2007 SYNTHESIS AND CHARACTERIZATION OF MCM-41 CONTAINING CeO2 Received 10 July 2006 PHAM ANH SON, NGUYEN DINH BANG, NGO SY LUONG Faculty of Chemistry, HaNoi University of Science, VietNam National University SUMMARY MCM-41 and cerium containing MCM-41 mesoporous materials were obtained by hydrothermal method under atmospheric pressure (the molar ratio SiO2/CeO2= x, x = 160, 80, 40, 20). The characteristics of all samples were investigated by ThermoGravimetric - Differential Thermal Analysis (TG-DTA), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Energy-Dispersive X-ray spectrometry (EDX) and nitrogen adsorption-desorption isotherms. The results indicated that: particles are sphere, uniform and pore size is about 50 nm; the pore systems are hexagonal structure, ordered arrangement; the samples have high surface area (> 600 m2/g) with narrow pore size distribution curve. Results of EDX showed that the SiO2/CeO2 molar ratios of samples were very similar to the molar ratios in gel. I - INTRODUCTION Porous materials, which have high surface area, high thermal and hydrothermal stability, are widely used in many fields: catalyst for oil refining, petrochemistry and chemical synthesis; adsorbents [1, 2]. Since 1930, microporous materials, especially zeolites, have attracted strong attention as solid acids, base and redoxcatalysts. However, zeolites present limitations when large molecules are involved. In 1992, researchers at Mobil Research and Development Corporation synthesized a type of mesoporous materials designated M41S. These of materials have highly ordered hexagonal array of unidimensional pores with a very narrow pore size distribution [3, 4]. They are interesting materials. In this paper, we report the results of studies concerning syntheses of MCM-41 and cerium containing MCM-41 mesoporous materials by hydrothermal method in which sodium silicate and cetyltrimethylammonium bromide were used as
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