Silver nanoclusters formation in ion-exchanged glasses by thermal annealing,UV-laser and X-ray irradiation

The Ag-exchanged commercial soda-lime silicate glasses were treated by three methods: thermal annealing, UV-laser irradiation, and X-ray irradiation, in order to promote the silver nanoclusters formation. Absorption spectrometry and electron spin resonance measurement results indicated that the silver ions transferred to silver atoms after the above three treatments. The silver atoms diffused and then aggregated to become nanoclusters after thermal annealing in air, or after UV-laser irradiation. However, X-ray irradiation, which induced defects and reduction of Ag⁰ atoms, would not promote the silver nanocluster formation. After annealing at 600 °C for 45 h, the spherical nanoclusters with a diameter of 3–8 nm were formed. The nanoclusters with a diameter of about 2 nm were formed after 30 min UV-laser irradiation without subsequent heating. The surface plasmon resonance peak position of silver nanoclusters changed from 411 nm after thermal annealing to 425 nm after UV-laser irradiation. The peak position shift was due to the nanoclusters size difference.