Preparation, structural and electrical characteristics of praseodymium modified lead titanate

Praseodymium modified lead titanate ceramics (Pb1-xPrxTi1-2yMoyFeyO3) with x = 0.02, 0.04, 0.06, 0.08 and 0.10 and y = 0.02 have been prepared by high temperature solid state reaction technique. Cold pressed pellets were sintered at 1100 degrees C for 2 h. Lattice parameters and crystal tetragonality was determined by X-ray diffraction analysis. All the synthesized samples show single phase with tetragonal structure. Tetragonality decreases and relative density increases with the increase in praseodymium substitution. Electrical characteristics which include dielectric properties and ac conductivity were studied as a function of temperature and frequency. Variation of dielectric constant with temperature shows a ferroelectric phase transition and transition temperature (T-C) decreases with increase in the praseodymium content. Nature of transition was studied and found to be diffused. Conductivity (sigma(ac)) was measured as a function of frequency in the range 10(3)-10(6) Hz at different temperature suggesting hopping mechanism. (C) 2011 Elsevier Ltd and Techna Group S.r.l. All rights reserved.