Optical and other structural properties of some zinc vanadate semiconducting glasses

In this paper we have reported the optical and other structural properties for different compositions of xV2O5–(1−x)ZnO (x = 0.5–0.8) semiconducting glasses. It has been observed that the density and the glass-transition temperature increase, while the molar volume decreases with the decrease of the V2O5 content in the compositions. It has also been observed from the analysis of FT-IR spectra that the network structure of these glasses consists of VO4-polyhedra. The fundamental absorption edge for the present glasses has been analyzed using the theory proposed by Davis and Mott. It has been observed that the fundamental absorption edge and cut-off wavelength shift towards red with the increase in V2O5 content. The composition dependence of the optical gap is consistent with that of the activation energy for the dc electrical conductivity.