Silver nanoclusters formation in ion-exchanged waveguides by annealing in hydrogen atmosphere

Abstract

Light waveguides containing silver, introduced by ion-exchange process in soda-lime glass, has been annealed in hydrogen atmosphere at temperatures in the 120-250 degrees C range. Annealings cause a near-surface precipitation of metallic silver to form nanometer-size clusters with good uniformity in size and spatial distribution. Hydrogen permeation and ion-exchange between hydrogen and sodium (which remains in the glass matrix after silver-for-sodium exchange) are steps of the annealing process. A further step is the diffusion of silver ions towards the surface, and its eventual precipitation, with an activation energy close to that measured for silver-sodium interdiffusion in glasses of comparable composition

Clustering of silver atoms in hydrogenated silver-sodium exchanged glasses

“…In glass matrices the metal cluster formation, which results from the combined techniques of ion-exchange and thermal treatments in reducing atmosphere ( [1] and references therein), may be regarded as a multistep process in which each step must to be overcome in order to allow the next one to occur. In our previous paper [2], we evidenced the process sequences and we showed how the ionic interdiffusion phenomenon that takes place constitutes the basic process for the formation of nanosized clusters.…”

Studies of copper–silver glass–metal nanocomposites

“…This completely corresponds to wileyonlinelibrary.com/journal/sia both the theoretical predictions [9] and known experimental data related to silver nanoparticles formation in glass. [10] Comparing AC04 and AC06 profiles, one can see that additional treatment in hydrogen leads to the appearance of one more minor peak corresponding to copper nanoparticles.…”

The remarkable transformation of nanoripples in glass-metal nanocomposite

“…Silver nanoparticles were formed in the subsurface layer of 1 mm thick soda-lime glass slides using Ag + -Na + ion exchange technique 15,16 in the Ag 0.5 Na 0.95 NO 3 bath at the temperature of 325 • C for 20 minutes. After the ion exchange, the samples were annealed in hydrogen at atmospheric pressure for 10 minutes at 250 • C. During the annealing, the silver ions in the subsurface region of the glass were reduced to neutral atoms, which aggregated into nanoparticles 17,18 with the diameter of a few nanometers.…”