Aerosol-Assisted Synthesis of Thiol-Functionalized Mesoporous Silica Spheres with Fe3O4 Nanoparticles

Thiol-functionalized mesoporous silica spheres having Fe3O4 nanoparticles are fabricated in one-pot by aerosol-assisted synthesis. A TEM image shows that Fe3O4 nanoparticles are successfully embedded within the mesoporous silica spheres. SEM images and SAXS profiles reveals that the encapsulating Fe3O4 nanoparticles do not affect the ordering of a mesoporous structure. The spherical morphologies are also well retained. The presence of cage-type mesopores with uniform size is confirmed by N-2 adsorption-desorption isotherms and TEM observations. The spray-dried thiol-functionalized particles with Fe3O4 nanoparticles effectively adsorb mercury (II) ions due to their strong interaction to thiol groups embedded in the framework. The particles with the amount of Fe3O4 nanoparticles (3.5 wt%) show a saturated magnetization (over 1.0 emu/g). This magnetic property is useful for practical collection with magnet.