Lithium–vanadium–tellurite glasses in the composition (V2O5)0.4–(Li2O)x–(TeO2)0.6−x; 0.10 ≤ x ≤ 0.50, were investigated for room temperature density and dc electrical conductivity in the temperature range 300 to 525K. The density increased with increasing Li2O up to 40mol% and then decreased for further doping of Li2O. Mixed electronic–ionic conduction was observed in the present set of glasses. The change-over of conduction mechanism from predominantly electronic to ionic was observed to be occurring at x = 0.4. The high temperature (T > θD/2) conductivity data obeyed Mott's small polaron hopping model and the low temperature (T < θD/2) conductivity was analyzed in the light of Motts variable-range hopping and Greaves variable-range hopping conduction models. Various physical parameters associated with theoretical models were estimated. It was the first time that Li-doped vanadotellurite glasses with the present composition had been investigated for density and dc conductivity, and the conductivity data for temperatures above and below (θD/2) were thoroughly analyzed in terms of theoretical models.

DC Conductivity in Some Alkali Doped Vanadotellurite Glasses. M.P.Kumar, T.Sankarappa: Solid State Ionics, 2008, 178[33-34], 1719-24