Preparation of novel magnetic hollow mesoporous silica microspheres and their efficient adsorption.

Magnetic hollow mesoporous silica microspheres (MHMSs) were successfully prepared by employing yolk-shell magnetic silica spheres as the template together with the coating of tetraethoxysilane (TEOS)/hexadecyl trimethoxysilane (C(16)TMS) hybrid. The microstructure and properties of MHMSs were studied by TEM, SEM, XRD, BET, and VSM characterizations. The average diameter of MHMSs was about 300 nm and the mesoporous shell thickness was totally around 70 nm. The 11 nm magnetite nanoparticles were homogeneously embedded in the mesoporous silica shell. Meanwhile, the adsorption and separation process of Rhodamine B were carried out to demonstrate that the material could be used for the adsorbent.