Effect of mixed glass-formers in Ag2O.MoO3.TeO2 system

Abstract

A comprehensive study of the partial replacement of tellurium by molybdenum in Ag2O.TeO2 binary glass system resulting in yAg2O.(1-y[xMoO3.(1-x)TeO2] ternary system has been carried out through X-ray diffraction, differential scanning calorimetry, electrical conductivity, X-ray photoelectron spectroscopy and infrared spectroscopy measurements. The observed variations in the glass transition temperature with change in composition were correlated to the bond strength, cross-link density and closeness of packing in the glass network. The conductivity measured at 25 °C shows two maxima for y = 0.30 at x = 0.2 and 0.4 and for y = 0.40 at x = 0.3 and 0.5. The enhancement of conductivity with an increase in MoO3 content is about half an order of magnitude. The observed changes in conductivity were attributed to the structural modifications resulting in the creation of nonbridging oxygen atoms which were distinguished from the bridging oxygen atoms through the deconvoluted O 1s XPS spectra. The deconvoluted Te 3d XPS spectra were assigned to various tellurium based structural units. Copyright © 1997 Elsevier Science Ltd. All rights reserved.