Electrical properties of V2O5-doped TlI

This paper reports the effect of heterogeneously doped vanadia on the ionic conductivity of thallium iodide (TlI). These compounds have been prepared and studied by X-ray diffraction, differential scanning calorimetry, scanning electron microscopy and electrical conductivity. The materials were found to be binary phase systems with the vanadia particles dispersed in the grains of TlI. The electrical conductivity shows an upward trend in the composition range x=0.1–0.5; however, with further increase in vanadia content, conductivity decreases. This behavior is attributed to disordering phenomena at interface boundaries and space-charge layers formed in the bulk grains of TlI. In addition to this, the increased content of vanadia in the system leads to the disappearance of the β?α phase transition of TlI, which is usually observed in the pure compound.