Relaxation dynamics in superionic glass nanocomposites

Abstract

We have studied the structural and electrical properties of several glass nanocomposite systems. The formation of nanowires, nanoparticles, and nanorods embedded in heat-treated xAg₂O-(1-x)MoO₃(x=0.2, 0.3, and 0.4) glass matrix and the growth of α-AgI nanocrystals and ZnO nanoparticles in the 0.7AgI-0.15Ag₂O-0.15(xZnO-(1-x)MoO₃) (x=0.05, 0.20, and 0.30) glass matrix and α-AgI nanocrystals in the xAgI-(1-x)(0.5Ag₂O-0.5MoO₃) (x=0.70, 0.75, and 0.80) glass matrices have been confirmed from X-ray diffraction and high-resolution transmission electron microscopic studies. We have investigated the electrical conductivity of these glass nanocomposites in a wide frequency and temperature range, and correlated them with their structures. We have analyzed the ac conductivity using a power law model. It has been observed that mobile ion concentration is independent of composition as well as temperature. It was also observed that the conductivity depends on the size of the nanoparticles grown in the host glass matrix. The scaling of the conductivity spectra reveals that the relaxation dynamics of Ag⁺ ions is independent of temperature and is also independent of composition at higher frequencies.