Barrier layer formation and PTCR effect in (1-x) Pb(Fe1/2Nb1/2)O3]-xPbTiO3 (x = 0.13) ceramics

TL;DR

This paper investigates the dielectric and resistive properties of PFN-xPT ceramics, revealing barrier layer formation and a PTCR effect, with implications for high dielectric applications and thermistor design.

Contribution

It demonstrates the occurrence of barrier layer formation and PTCR effect in PFN-xPT ceramics with x=0.13, providing new insights into their electrical behavior.

Findings

High dielectric constant at low frequencies due to barrier layers

Resistivity shows a PTCR effect beyond the Curie temperature

Diffuse phase transition observed in the ceramics

Abstract

(1-x)Pb(Fe1/2Nb1/2)O3-PbTiO3(PFN-xPT)Ceramics with x = 0.13 sintered at 1473K show diffuse phase transition and very high dielectric constant at lower frequencies.The high value of dielectric constant at lower frequencies is shown to be due to the barrier layer formation.The resistivity of the PFN-xPT ceramics, obtained by complex impedance analysis, initially decreases with temperature and then shows an upward trend beyond the ferroelectric Curie point reminiscent of BaTiO3 based thermistors with PTCR effect.