Structural, Optical, Dielectric And Thermal Properties Of Molybdenum Tellurite And Borotellurite Glasses

Molybdenum tellurite and borotellurite glasses were prepared and structure-property correlations were carried out by density, X-ray diffraction, dielectric measurements, differential scanning calorimetry, UV-visible, infrared, Raman and B11 Magic Angle Spinning Nuclear Magentic Resonance studies. The short-range structure of molybdenum tellurite glasses consists of TeO4, TeO3 and MoO6 structural units. Increase in MoO3 concentration from 20-50 mol% decreases the Te-O coordination from 3.48 to 3.26 and lowers the glass transition temperature (Tg) due to increase in the concentration of weaker Mo-O bonds at the expense of stronger Te-O bonds. Refractive index of molybdenum tellurite glasses increases while the dielectric constant decreases with increase in MoO3 concentration. The addition of B2O3 in the tellurite network enhances Tg and suppresses the tendency towards crystallization.