Fabrication and characterization of Ag-SiO2 composite hollow nanospheres

Ag-SiO2 composite hollow nanospheres were synthesized by impregnation of hollow silica nanospheres (HSNSs), which were prepared by templating CaCO3 nanoparticles, in [Ag(NH3)2]NO3 aqueous solution followed by heat treatment. The straightforward process generates composite materials containing Ag nanoparticles, with the average size of 6–10 nm in diameter, uniformly dispersed and mainly distributed on the shells or between the spaces of the HSNSs. The Ag-supported HSNSs were characterized through TEM, EDS, and XPS. Furthermore, ASS, XRD and UV-Vis analyses demonstrated that higher loading efficiency could be achieved under the optimum loading conditions of a silver precursor solution of 0.08 M, pH = 9.0 and HSNSs with a BET surface area of 830.4 m2/g. C 2006 Springer Science + Business Media, Inc.