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Mesoporous silicas SBA-15 are modified with β-Cyclodextrins (β-CD) by simple grafting method. β-CD functionalized SBA-15 was characterized by Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), nitrogen adsorption–desorption measurements, thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). Furthermore, the applicability of it is investigated through studying the adsorption properties of clenbuterol. It showed better adsorption capacities of clenbuterol than pure SBA-15. β-CD functionalized SBA-15 material has the potential applications in the treatment of clenbuterol contamination in food and environment science.

Thiol-functionalized three-dimensional (3D) mesoporous silica FDU-12 and SBA-15 with ordered pore were prepared. All the obtained materials were characterized by small angle X-ray scattering (SAXS), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Mesoporous silica FDU-12 (Fm3m) materials with various unit cell sizes, multifaceted pore were convenient for the interaction of subject and object; the 2D SBA-15 mesoporous silica materials with short and order pore channel were better than the traditional SBA-15 mesoporous silica, in which the pore channel can be used fully. 3D mesoporous silica FDU-12 is used as a sensing material to reconstruct QCM sensors to enhance the stability and this material is an ideal material to deal with heavy metal ions in water.

In this paper, ordered mesoporous SBA-15 silica was synthesized by the hydrothermal method, and then a series of CoFe₂O₄/SBA-15 nanocomposites were synthesized by a facile impregnation method. X-ray diffraction and N₂ adsorption–desorption isotherms were used to characterize the microstructure and morphology of SBA-15 and CoFe₂O₄/SBA-15 nanocomposites. CoFe₂O₄ nanoparticles presented spinel phase structure and existed in the mesopores of SBA-15. The magnetic response of CoFe₂O₄/SBA-15 nanocomposites was characterized with vibrating sample magnetometer (VSM). The adsorption efficiency of CoFe₂O₄/SBA-15 nanocomposites for methylene blue increased firstly with the increasing CoFe₂O₄ content, and then decreased. Sample-2 (SBA-15: CoFe₂O${}_4=1$: 0.1 in the precursor) not only presented the best adsorptive performance, but also could be separated and retrieved effectively by magnetic separation technique.

Mn K-edge absorption measurements were carried out on α-Mn₂O₃ and Mn₃O₄ nanocrystals supported on a mesoporous silica, SBA-15. The X-ray absorption near edge structure (XANES) spectra demonstrate the existence of the oxidation states of Mn (2+ and 3+) in Mn₃O₄ and Mn (3+) in Mn₂O₃, those ions were present in different octahedral environments. Meanwhile, XANES data demonstrate that some Mn atoms that are bonding to the inner wall of the channels as isolated species, may exist as Mn⁴⁺ in Mn₂O₃/SBA-15. In addition, the structure, texture, and electronic properties of nanocomposites were also studied using various characterization techniques including X-ray diffraction (XRD) and laser Raman spectroscopy (LRS). The formation of the hausmannite Mn₃O₄ and bixbyite Mn₂O₃ structures has been confirmed clearly by XRD. The prepared nanocomposites of MnO_x showed significant catalytic activity towards CO oxidation below 523 K.