High-temperature electrical conductivity of the xNBT–(1-x)LMT ceramics: verification of Meyer-Neldel rule

Abstract

Electrical conductivity behaviour of x(Na0.5Bi0.5)TiO3-(1-x)La(Mg0.5Ti0.5)O3 ceramics with x ranging from 0.95 to 0.8 was analysed in the temperature range from 300 K to 800 K at microwaves (1MHz – 1GHz frequency region). Analysis of calculated DC conductivity parameters has shown that the activation energy changes at about 690 K which could be associated with the phase change in these materials. The logarithm of preexponential factor of DC conductivity changes linearly according to the activation energy, i.e. it follows Meyer-Neldel rule both below and above the phase transition point.