Ferroelectric phase transition in Pb(Cd1/2Mo1/2)O-3 ceramics

The effects of Cd-doping on structural, dielectric and electrical propertie s of lead molybdate (PbMoO3) have been investigated. Polycrystalline sample s of Cd-doped lead molybdate Pb(Cd1/2Mo1/2)O-3 were synthesized by solid-st ate reaction technique. The structural study of the compound, carried out b y X-ray diffraction (XRD), shows the formation of a single-phase compound. Detailed studies of relative dielectric constant (epsilon (r)) and loss tan gent (tan delta) of the compound both as a function of frequency (10(3)-10( 4) Hz) and temperature (30-320 degreesC) at 10 kHz suggest that the compoun d undergoes a phase transition at 66 degreesC. Activation energy of the com pound was found to be 0.90 eV in the paraelectric phase. The temperature va riation of resistivity of the compound suggests that the compound has negat ive temperature coefficients of resistivity (NTCR). (C) 2001 Elsevier Scien ce B.V. All rights reserved.