Physical, structural and elastic properties of silicate lithium niobate vanadium tellurite glass system

Abstract

This thesis reports a concise study of physical, structural and elastic properties of tellurite based glasses in search of strong materials for improving their potentials as commercial glasses in wide range of applications. A series of glass samples with the composition (65.0-x)TeO2–14.9Li2O–15.0Nb2O5–5.0SiO2–(x)V2O5 with 0 = x = 6.0 mol% was prepared via melt quenching technique. These samples were characterized by X-ray diffraction (XRD), energy dispersive X-ray (EDX) spectroscopy, atomic force microscopy (AFM), differential thermal analysis (DTA), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, Vicker’s hardness and ultrasonic measurement. XRD pattern verified the true amorphous nature of the prepared glass and the EDX spectra detected the presence of right elements in the glass composition. The AFM analysis manifested the surface roughness of the glass sample which increased with the increase of V2O5 content, indicating its three-dimensional growth. The synthesized transparent samples revealed good thermal stability over a wide glass formation region. FTIR and Raman spectra showed the incorporation of vanadium slightly modified the glass structure due to the introduction of a small amount of vanadium content in the glass system. The Vicker’s hardness values and ultrasonic elastic properties were found to increase with the increase of vanadium content and this showed the glass structure was more rigid and contained the fewest non-bridging oxygen. The sound attenuation coefficients and internal friction of the glass system were found to decrease along with the increase of vanadium concentration due to the absorption and scattering phenomena. The inclusion of V2O5 in the tellurite based glass system was verified to improve its physical, structural and elastic properties and it promises a wider application in industries.