Preparation and Characterization of Mesoporous Silica-Supported and Encapsulated Nano-Metal Particles

Metal nanoparticles supported on the core-shell particles with SiO2 as core and mesoporous SiO2 as shell and mesoporous SiO2-encapsulated metal nano particles supported on SiO2 particles were prepared in this work.The results showed that SiO2 particles as cores could be coated by mesoporous SiO2 shell with aid of CTAB template and the direction of mesoporous channels was perpendicular to the surface of SiO2 core.Pt nanoparticles could be homogeneously supported on the surface of mesoporous SiO2 shell with aid of PVP.SiO2 particles functionalized with APS could support metal nanoparticles.The further study indicated that the mesoporous SiO2-encapsulated metal nanoparticles supported on SiO2 particles could be prepared with SiO2 particles-supported metal nanoparticles as cores,NH3·H2O,ethanol and water as dispersant,CTAB as template and TEOS silica precursor.It was also found that the thickness of mesoporous SiO2 shell could be controlled by the content of TEOS.