PREPARATION AND CHARACTERIZATION OF Ag(CORE)/SiO2(SHELL) NANOPARTICLES

Ag nanoparticles were synthesized by using thermal decomposition of Ag+–oleate complex. The mean size of Ag nanoparticle was confirmed as 10 nm with transmission electron microscopy (TEM). The crystal structure and optical property of Ag nanoparticles were studied with X-ray powder diffraction (XRD) and UV–vis spectroscopy, respectively. The Ag nanoparticles were used as seeds for Ag(core)/SiO2(shell) nanocomposite particles. TEM images of Ag(core)/SiO2(shell) nanocomposite particles showed that silver core was coated with 15 nm thickness of SiO2 shell. The thickness of SiO2 shells could be conveniently controlled by changing the concentration of sol–gel precursor or reaction time. The composition of Ag(core)/SiO2(shell) nanocomposite particle was investigated with energy-dispersive X-ray (EDX) spectrometer.