Gadolinium doping of vanadate-tellurate glasses and glass ceramics

In order to further elucidate the local structure of ternary xGd2O3(100 - x)[0.7TeO2 0.3V2O5] glasses with x = 0, 5, 10, 15, 20 mol%, FTIR spectroscopy, XRD diffraction and density measurement were performed. FTIR and density data show that by increasing the gadolinium ions content of the samples the excess of oxygen may be accommodated by the inter-conversion of some [VO4] into [VO5] structural units and of [TeO3] into [TeO4] units. The composition of the heat-treated glasses was found to consist mainly of the Te2V2O9 crystalline phase. Varying x between 15 and 20 mol% Gd2O3 produces structural modification having as result an increase of the glass network polymerization degree. Accordingly, the gadolinium ions play a particular role related to the improvement of the homogeneity of the glasses and in accommodating the glass network with the excess of oxygen.