Hopping Mechanism and Impedance Properties of Mg Doped NBT-KBT Solid Solution near Ambient Temperature

Abstract

Solid state reaction route has been utilized to synthesize Na0.42K0.08Bi0.50Mg0.05Ti0.95O3−δ solid solution. Impedance plots are used to examine electrical attributes as a function of frequency (100 Hz –1 MHz) and temperature (10 °C–50 °C). The existence of bulk and grain boundary contributions in the impedance has been revealed by the nature of Nyquist plots. The presence of conductivity relaxation in the sample is indicated by the merging of normalized plots of modulus ( M ″ ) profile. The ac conductivity follows Jonscher’s Power law, and suggested the correlated barrier hopping (CBH) conduction mechanism, whereas, the dc conductivity is found to be Arrhenius dependent. The activation energies computed from the conductivity and relaxation patterns are nearly identical which are 1.30 eV and 1.39 eV respectively.