EFFECT OF MIXED GLASS-FORMERS IN AG2O.MOO3.TEO2 SYSTEM

A comprehensive study of the partial replacement of tellurium by molyb denum in Ag2O.TeO2 binary glass system resulting in yAg(2)O.(1-y[xMoO( 3).(1-x)TeO2] ternary system has been carried out through X-ray diffra ction, differential scanning calorimetry, electrical conductivity, X-r ay photoelectron spectroscopy and infrared spectroscopy measurements. The observed variations in the glass transition temperature with chang e in composition were correlated to the bond strength, cross-link dens ity and closeness of packing in the glass network. The conductivity me asured at 25 degrees 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 structura l modifications resulting in the creation of nonbridging oxygen atoms which were distinguished from the bridging oxygen atoms through the de convoluted O 1s XPS spectra. The deconvoluted Te 3d XPS spectra were a ssigned to various tellurium based structural units. Copyright (C) 199 7 Elsevier Science Ltd.