Thermoanalytical, structural and ionic conductivity studies on 50Li <inf>2</inf>O-45P <inf>2</inf>O <inf>5</inf>-5Nb <inf>2</inf>O <inf>5</inf> glass

Thermal, structural and ionic conduction characteristics of lithium niobophosphate glass (mol% 50Li 2O-45P 2O 5-5Nb 2O 5) are reported and compared with the characteristics of lithium metaphosphate glass (mol% 50Li 2O-50P 2O 5). The presence of the second glass former (Nb 2O 5) not only improves the chemical durability and thermal stability but also enhances the conduction characteristics of lithium metaphosphate glass. The ionic conductivity measurements are reported in the extended temperature range i.e. above the glass transition temperature (T g) where a non-Arrhenius temperature dependence of the ionic conductivity has been observed. The ion conduction process below T g is governed by a well-defined activation energy whereas the conduction process above T g is activated by at least two different phenomena discussed in the light of the structural relaxation and crystallization. © 2012 Elsevier B.V.