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 m(2)/g. (c) 2006 Springer Science + Business Media, Inc.