IR and Raman investigation on the structure of (100-x)[0.33B2O3-0.67ZnO]-xV2O5 glasses

Glasses with molar composition of (100-x)[0.33B(2)O(3)-0.67ZnO]-xV(2)O(5), x = 0, 5, 10, 15 and 20, were prepared, and the effect of V2O5 on the structure of the glass was investigated by IR and Raman spectroscopy, TEM and DTA. This investigation shows that [BO3], [BO4] and [VO4] structural units are the predominant coordination polyhedra in the borovanadate glass. From the vanadium-free zinc borate glass, meta-, di-, pyro- and orthoborate groups were observed. Adding V2O5 leads to the random substitution of [BO3] or [BO4] units in these borate groups by the [VO4] units, forming corresponding borovanadate groups. With increasing V2O5 content, the transition temperature of the glass decreases, that comes from the decrease of the interconnection of the structure units and the substitution of O-B-O by weaker O-V-O linkages. (c) 2006 Elsevier B.V. All rights reserved.