Microstructure, thermal, optical and dielectric properties of new glass nanocomposites of SrTiO3 nanoparticles/clusters in tellurite glass matrix

Abstract

New glass nanocomposites (GNCs) of the nominal compositions [(100-x) TeO2–xSrTiO3] with x=5, 10 and 15 (in mol%) were prepared. The glassy phase in the GNCs samples was established by X-ray diffraction (XRD) and Differential thermal analysis (DTA) studies. The SrTiO3 nanoparticles/clusters embedded in tellurite glass matrix for GNCs were identified by transmission electron microscopic (TEM) and confirmed by Fourier transform infrared (FTIR) study. The optical transmission (at x=5) and the electron spin resonance (ESR) studies for the GNCs samples indicated that the presence of Ti3+ ions in tetragonal distorted octahedral sites. The variation of the thermal, density (ρ) and the molar volume (Vm) of the GNCs samples with increasing SrTiO3 were discussed in terms of the structural modifications that take place in the glass matrix. The dielectric properties and ac conductivity of the GNCs samples cannot be explained on the basis of the proportion of Ti3+ ions only.