Preparation of Ag nanocrystals embedded silicate glass by field-assisted diffusion and its properties of optical absorption

Ag nanocrystals embedded silicate glass was successfully prepared by solid-state field-assisted diffusion, combined with post-annealing process. The changes of glass structure, the chemical states of Ag and O species, the microstructures of Ag nanocrystals, as well as the properties of optical absorption were studied for the as-diffused and post-annealed samples. The result showed that after the field-assisted diffusion process, some Ag⁺ ions replaced the alkaline ions in the glass matrix. Meanwhile, other Ag⁺ ions were reduced to Ag⁰ atoms occupying the interspaces of the network and Ag⁰ atoms clusters with small size were formed. This caused the relaxation of the glass network and the deceasing of force constant for Si–O linkage. After post-annealing process, bigger size of Ag nanoparticles were formed, which caused the peak corresponding to the surface plasmon resonance (SPR) observed.