Effect of Fe doping on dielectric, ferroelectric and pyroelectric properties of PLZT (8/65/35)

Abstract

Fe modified Pb0.92La0.08(Zr0.65Ti0.35)O3 (PLZT) was prepared by the conventional method based on the solid state reaction of mixed oxides. The x-ray analysis clearly shows the formation of a PLZT single rhombohedral phase. The crystallite size calculated from Sherrer's equation and the grain size determined from microstructures were found to decrease with Fe doping up to 4%. Calculations carried out for the peak intensity of the x-ray diffraction analysis suggest that Fe occupied the A site up to 4% doping and beyond that it occupied both A and B sites in the ABO3 perovskite structure. Dielectric and pyroelectric measurements show a peak at around the Curie transition temperature. The width of the peaks was found to increase with Fe doping along with decreasing peak dielectric and pyroelectric maxima up to 4%. The P–E loop measurements of PLZT samples with Fe doping up to 6% have shown saturated single loops. Pr and EC from the P–E loop were found to increase with increasing applied field and reached saturation at higher applied fields (25 kV cm−1). However, 8% and 10% Fe doped PLZT have shown double unsaturated hysteresis loops. This anti-ferroelectric phase in Fe doped PLZT samples beyond 8% doping is expected to be due to the occupation of Fe in the B site replacing the Ti atom in the ABO3 perovskite structure.