Characterization of V-MCM-41 Mesoporous Materials

阅读量：

作者：

展开

摘要：

A series of vanadosilicate V-MCM-41 mesoporous materials with various compositions have been synthesized using vanadium sulfate as the source of vanadium. Hexadecyltrimethylammonium bromide was used as a surfactant in the synthesis. The samples were characterized with nitrogen sorption, X-ray diffraction, framework FTIR , diffuse reflectance UV-visible spectroscopy, differential thermal analysis, thermogravimetric analysis, scanning electron microscopy and transmission electron microscopy. The results show that the solid products had the MCM-41 structure and contained only atomically dispersed vanadium consistent with framework vanadium in V-MCM-41. N 2 sorption measurements and TEM demonstrated the high mesoporosity of V-MCM-41. The incorporation of vanadium into MCM-41 decreased the surface area to some extent. The morphology of V-MCM-41 was plate with stepped and smooth surfaces. TEM reveals a regular hexagonal array of uniform channels with curved and rectilinear morphologies. The hexagonal array structure of uniform pore size was observed by TEM. It is proved that the pores were highly aligned.

展开

关键词：

Bibliography, Experimental/ crystal microstructure differential thermal analysis Fourier transform spectra heat treatment infrared spectra materials preparation noncrystalline structure porosity porous materials reflectivity scanning electron microscopy sorption transmission electron microscopy ultraviolet spectra visible spectra X-ray diffraction/ Na 2O-VO 2-SiO 2 mesoporous materials hexadecyltrimethylarnmonium bromide surfactant synthesis N 2 sorption measurements mesoporosity morphology stepped surfaces smooth surfaces regular hexagonal array uniform channels X-ray diffraction framework Fourier transform infrared spectroscopy diffuse reflectance ultraviolet-visible spectroscopy differential thermal analysis thermogravimetric analysis characterization curved morphology rectilinear morphology hexagonal array structure uniforrn pore size scanning electron microscopy transmission electron microscopy atomically dispersed V Na 2O-VO 2-SiO 2 N 2/ A6140 Structure of amor