SYNTHESIS AND CHARACTERIZATION OF CaCO ₃ @SiO ₂ @AG CORE–SHELL COMPOSITES

CaCO 3 @SiO 2 @Ag core–shell composites were successfully synthesized in a two-step process. The silica shell layers were first prepared by Stöber method in the liquid mixture of CaCO 3 . Then, silver shell particles were subsequently obtained by reducing AgNO 3 in the liquid mixture of CaCO 3 @SiO 2 . The products were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), respectively. It was found that CaCO 3 @SiO 2 @Ag core–shell composites were successfully obtained. The SiO 2 was confirmed as amorphous with 2–10[Formula: see text]nm, which acted as a bridge between CaCO 3 and Ag.