Impedance and a.c. conductivity studies of Ba(Pr1/2Nb 1/2)O3 ceramic

Abstract

Impedance and electrical conduction studies of Ba(Pr1/2Nb 1/2)O3 ceramic prepared through conventional ceramic fabrication technique are presented. The crystal symmetry, space group and unit cell dimensions were estimated using Rietveld analysis. X-ray diffraction analysis indicated the formation of a single-phase cubic structure with space group, Pm3m. EDAX and SEM studies were carried out to study the quality and purity of compound. To find a correlation between the response of the real system and idealized model circuit composed of discrete electrical components, the model fittings were presented using impedance data. Complex impedance as well as electric modulus analyses suggested dielectric relaxation to be of non-Debye type and negative temperature coefficient of resistance character. The correlated barrier hopping model was employed to successfully explain the mechanism of charge transport in Ba(Pr1/2Nb1/2)O 3. The a.c. conductivity data were used to evaluate density of states at Fermi level, minimum hopping length and apparent activation energy. © Indian Academy of Sciences.