Eur. Phys. J. Plus (2016) 131: 421
https://doi.org/10.1140/epjp/i2016-16421-y

Regular Article

Ionic-to-electronic conductivity of glasses in the P₂O₅-V₂O₅-ZnO-Li₂O system

Laboratoire de Physico-Chimie des Matériaux Minéraux et leurs Applications, Centre National de Recherches en Sciences des Matériaux, B.P. 95, 2050, Hammam-Lif, Tunisia

^* e-mail: sdirinasr@yahoo.fr

Received: 23 September 2016
Accepted: 10 November 2016
Published online: 6 December 2016

Abstract

Glasses having a composition 15V₂O₅-5ZnO-(80-x P₂O₅-xLi₂O (x = 5 , 10, 15 mol%) were prepared by the conventional melt quenching. Conduction and relaxation mechanisms in these glasses were studied using impedance spectroscopy in a frequency range from 10 Hz to 10 MHz and in a temperature range from 513 K to 566 K. The structure of the amorphous synthetic product was corroborated by X-ray diffraction (disappearance of nacrite peaks). The DC conductivity follows the Arrhenius law and the activation energy determined by regression analysis varies with the content of Li₂O. Frequency-dependent AC conductivity was analyzed by Jonscher's universal power law, which is varying as , and the temperature-dependent power parameter supported by the Correlated Barrier Hopping (CBH) model. For x = 15 mol%, the values of confirm the dominance of ionic conductivity. The analysis of the modulus formalism with a distribution of relaxation times was carried out using the Kohlrausch-Williams-Watts (KWW) stretched exponential function. The stretching exponent, , is dependent on temperature. The analysis of the temperature variation of the M” peak indicates that the relaxation process is thermally activated. Modulus study reveals the temperature-dependent non-Debye-type relaxation phenomenon.