Electrical impedance spectroscopy and aging behavior of glasses containing silver oxide and metallic silver nanoparticles

In this study we present the data on the observed electrical behavior of glasses in the xAg2O(1 − x)PbO3B2O3 [0 ⩽ x ⩽ 1] system with the underlying aim of analyzing the contribution of silver nanoparticles in these glasses. We measured the dielectric response in the frequency region 10 Hz–30 MHz at room temperature and at 1 kHz in the temperature region of 10–300 K; dc conductivity was measured in the region of 80–300 K. Analysis of the data shows that the parameters that describe the properties do not vary linearly with the content of Ag2O (parameter x) and the relative contribution of crystalline precipitates of Ag2O and that of Ag nanoparticles must be taken into consideration. Therefore, we interpret the electrical data in conjunction with the structural information obtained by X-ray diffraction, scanning electron microscopy (SEM) and photoluminescence (presented elsewhere) and show how the electrical properties reveal the presence of silver nanoparticles. Our data show that there is a clear break in the trend at x = 0.5; at this composition SEM micrographs show a large amount of silver nanoparticles dispersed in the body of the glass. We also describe changes in the glasses that we observe when they are exposed to air for a long period.