Superbasic sites have been generated on the mesoporous silica materials for the first time, through a new strategy to prepare the MgO-modified SBA-15 in one-pot synthesis and then to disperse KNO3, possessing the good textural structure of the host and the high basic strength (H -) of 27.0. The in situ coated Mg species passivated the silanol groups on the surface of siliceous SBA-15 so that the mesostructure of SBA-15 could be reserved after the composite was loaded with KNO3 and activated at high temperature. Existence of the special protection layer of MgO on the surface of SBA-15 was also beneficial for decomposition of KNO3 to form superbasic sites on the mesoporous silica. The influence of coating amount of MgO on the protection of the textural properties of SBA-15 is examined and discussed in terms of consuming surface silanol groups. Dispersion and decomposition of KNO3 on the MgO layer is also explored. Other metal oxides such as CaO, ZnO, and Al2O3 are in situ coated on the surface of SBA-15 through one-pot synthesis and their function of protecting SBA-15 is evaluated for comparison with MgO.

Aluminum‐containing plugged mesoporous silica has been successfully prepared in an aqueous solution that contains triblock copolymer templates, nitrates, and silica sources but without using mineral acid. The acidity of the solution can be finely tuned from pH 1.4 to 2.8 according to the amount of the introduced aluminum species which ranged from an Al/Si molar ratio of 0.25/1 to 4.0/1. The aluminum nitrate additive in the starting mixture, along with the weak acidity produced by the nitrates, contributes to the formation of plugged hexagonal structures and the introduction of different amounts of aluminum species into the mesostructure. Characterization by X‐ray diffraction, transmission electron microscopy, and N2 sorption measurements show that the Al‐containing plugged silicas possess well‐ordered hexagonal mesostructures with high surface areas (700–860 m2 g–1), large pore volume (0.77–1.05 cm3 g–1) and, more importantly, combined micropores and/or small mesopores in the cylindrical channels. Inductively coupled plasma–atomic emission spectrometry results show that 0.7–3.0 wt % aluminum can be introduced into the final samples. 27Al MAS NMR results display that about 43–60% aluminum species are incorporated into the skeleton of the Al‐containing silicas and the amount of the framework aluminum increases as the initial added nitrates rises. Scanning electron microscopy images reveal that the directly synthesized Al‐containing plugged silica has a similar morphology to that of traditional SBA‐15. Furthermore, the Al‐containing plugged samples have excellent performances in the adsorption and the catalytic decomposition of isopropyl alcohol and nitrosamine. Finally, the direct synthesis method is used to produce plugged mesoporous silicas that contain other metals such as chromium and copper, and the resultant samples also show good catalytic activities.

Solid‐state grinding is a simple and effective method to include guest species into the channels of ordered mesoporous materials with a different degree of filling. After calcination, a monolayer or several monolayers of guest species can not only form highly dispersed oxide species and other surface species on the hosts whether the template is occluded in the channels or not, but the guest species can also fill the mesoporous channels in the host and thus lead to nanowires or nanoarrays. Solid‐state salt inclusion is faster and more convenient than other inclusion routes. The absence of a solvent not only saves the time otherwise needed for evaporation but also leads to a higher degree of filling through a simple inclusion step as the void space in the pores is not occupied by the solvent. Also, the lack of competitive adsorption of solvent molecules enhances the interaction between the guest species included and the silica wall, which facilitates the high dispersion of oxide species. However, host–guest interactions that are too strong may disturb the self‐crystallization of guest species in the mesopores leading to imperfect nanocasting of the mesostructure.

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The adsorption and catalytic degradation of nitrosamines by zeolite A with cesium, potassium, sodium, or calcium cation was systemically studied in the research reported in this article. The results of instantaneous adsorption, temperature-programmed surface reaction, and in situ Fourier transform infrared spectroscopy measurements proved the adsorption of the bulky nitrosamines, N′-nitrosonornicotine (NNN) and Nnitrosopyrrolidine, on the zeolite A with a pore diameter of only 0.2-0.5 nm. Moreover, thermogravimetricmass spectrometry analysis revealed the different adsorption and degradation manners of NNN on various samples of zeolite A, which will be discussed in terms of electrostatic attraction and geometric confinement provided by the zeolite.

Mesoporous silica with Ia3d structure has been successfully prepared utilizing a triblock copolymer (EO20PO70EO20)−acetate mixture for structure direction in aqueous solution over a wide pH range, even above the isoelectric point of silica, where the pH value could be finely tuned by varying the concentration of HCl and/or acetate. Characterization by XRD, TEM, and N2 sorption measurements show that the cubic Ia3d materials possess high surface areas (about 900 m2/g), large pore volumes (about 1.2 cm3/g), and uniform pore diameters (about 9.2 nm). Further, the phase diagram in the SiO2−P123−ZnAc2−H2O−HCl system is drawn to map the range of cubic mesophase. Salt effect has been investigated during the phase transformation process, which reveals that the nature and concentration of cations can also determine the mesostructure. In addition, when two different acetates are introduced into the solution at one time, metal oxides-modified cubic mesoporous silica can be directly synthesized. Among others, copper-modified cubic samples, prepared by this direct method, display superior properties in the NO2-TPD experiments. The lower acid concentration in the acetate-modulated synthetic system favors the direct incorporation of metal oxide species and this discovery may offer us a new perspective to better understand the formation mechanism of ordered mesoporous materials.

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