The sliver-silica composite grains with different concentrations were prepared by sol-gel technology. The feature, structure, and optical absorption properties of silver nanoparticles were characterized by transmission electron microscope (TEM), X-ray diffraction (XRD), and ultraviolet visible near infrared (UV-Vis-NIR) absorption spectrometer. The results indicate that the silver nanoparticles (15～20 nm) have face-centered cubic crystal structure and are homogenously distributed on the surface of silica. It was found that the peak of plasma resonant absorption locates at about 410 nm for silver nanoparticles, and the intensity of absorption increases with that of the silver concentration.

silver nanoparticles; silica; sol-gel technology