Relation among optical, thermal and thermo-optical properties and niobium concentration in tellurite glasses

Abstract

In this work, optical, thermal, thermo-optical and spectroscopic properties of the 80TeO(2)-(20-x)Li(2)O-xNb(2)O(5) (x=5, 10 and 15 mol%) glasses were investigated by using the thermal lens spectrometry, X-Ray diffraction, Raman spectroscopy, modulated differential scanning calorimetry and Brewster angle method. The influence of Nb(2)O(5) in the glass structure was interpreted by the thermal diffusivity, specific heat, thermal conductivity, temperature coefficient of the optical path length, refractive index and band gap energy. The calculated optical basicity and polarizability allowed bettering understanding the obtained results, reinforcing the assumption on the glass structural change. Crown Copyright (C) 2010 Published by Elsevier B.V. All rights reserved

Optical and thermal properties of TeO2–B2O3–Gd2O3 glass systems

“…Thermal diffusivity of gadolinium borotellurite glass achieves the maximum at x = 1.0 mol% with the value of 2.46902 × 10 −7 m 2 s , which is lower than that of window glass 3.4. The values of thermal diffusivity obtained in the present work are lower as compared with the results obtained for other tellurite glasses, 2.7 × 10 −7 m 2 /s to 3.0 × 10 −7 m 2 /s and from 3.1 × 10 −7 m 2 /s to 3.4 × 10 −7 m 2 /s as reported in the literature [35,36]. Previously in [37] it has been reported that the maximum in thermal diffusivity corresponds to the minimum molar volume.…”

Fluorescence quantum yield of Yb3+-doped tellurite glasses determined by thermal lens spectroscopy

“…2. The WeO À and W]O bonds of WO 4 and WO 6 units are observed around 920 cm À1 , defining the phonon energy of TW glass [5], while for TL glass the phonon energy is around 750 cm À1 , corresponding to the stretching vibrational mode of TeeO in the trigonal-pyramid units [20]. From the spectra it can be noted that the ratio of the intensities of absorptions associated to the TeO 4 trigonal bipyramid units (at 670 cm À1 ) and TeO 3þ1,3 trigonal pyramid units (at~750 cm À1 ) is higher in TW than TL glass, what is also related to the observed red shift in the fundamental absorption band.…”

Effects of Fe2O3 replacement of ZnO on elastic and structural properties of 80TeO2–(20−x)ZnO–xFe2O3 tellurite glass system

“…In addition, tellurite glass is non-hygroscopic compared to phosphate and borate glasses [9,10]. As a conditional glass former, tellurium oxide needs a modifier such as alkali metal, alkaline earth metal oxide and transition metal oxide (TMO) or other glass modifiers [11,12] in order to form glass. Interestingly, TeO 2 glass is able to maintain a lower melting point range [10,13] and shows increase in glass transition temperature (T g ) when combined with some modifiers [4,14].…”

“…A number of intermediate oxides have been doped into tellurite glass systems and showed behaviour of either a glass former which is incorporated in the glass network [4,[21][22][23] or as a modifier which is not part of the glass network [4,12,21] but with increased formation of non-bridging oxygen (NBO) [11]. ZnO in particular has acted as a network former both in binary (1 − x)TeO 2 -xZnO [24] and ternary (90 − x)TeO 2 -10Nb 2 O 5 -(x)ZnO [25] glass systems.…”