Preparation and morphology control of magnetic mesoporous silica via metalorganic amphiphiles self-assembly

A facile method, which was based on the cationic surfactant self-assembly and oxidation, was designed to fabricate magnetic mesoporous silica (MMS). Three types of metalorganic amphiphiles with a terminal ferrocene moiety were synthesized and used as structure-directing agents and iron source to prepare magnetic mesoporous silica. Among all the surfactants, FcC11PyBr (11-[(ferrocenyl carbonyl)oxy]-undecyl pyridinium bromide) exhibited the best ability to produce mesopores with tetraethoxysilane at a suitable molar ratio. Using FcC11PyBr as the structure-directing agent, it was also easy to control the morphology of MMS, which was turned from irregular powder to smooth sphere. After the oxidation reaction at 573 K, the MMS material showed an obvious magnetic property, with a large surface area and pore volume. The MMS was characterized by X-ray diffraction, N2 adsorption–desorption isotherms, SEM, TEM, SQUID magnetometry and X-ray photoelectron spectrometry. The MMS was found to have a good absorptivity and used as magnetic adsorbent to remove some dye pollutants in water.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Magnetic mesoporous silica was prepared via metalorganic amphiphiles self-assembly. ► The morphology of magnetic mesoporous silica could be turned from powder to sphere. ► Magnetic mesoporous silica had good removal property by external magnetic field.