Silver nanocluster formation in soda-lime silicate glass by X-ray irradiation and annealing

Silver nanocluster formation and dissolution was observed in a soda-lime silicate glass with 0.02 wt% of silver after X-ray irradiation followed by annealing. Absorption spectrometry and electron spin resonance measurement results indicated that the silver ions transferred to silver atoms after irradiation. The silver atoms diffused and then aggregated to become nanoclusters after annealing at high temperatures (such as > 300 degrees C). The nanoclusters grew during the first 15 min at 420 degrees C, and then slowly dissolved over a longer period. The mean nanocluster size estimated based on Mie theory was similar to 4 nm at 420 degrees C for 1 h, decreasing to similar to 2 nm after heating for 48 h. The induced defects trapped electrons from silver nanoclusters, and the dissolution of silver nanoclusters to form silver ions results in a net loss in the system energy. The nanoclusters dissolved completely at 560 degrees C for 1 h. (C) 2007 Elsevier B.V. All rights reserved.