6533b871fe1ef96bd12d1939

RESEARCH PRODUCT

Normal and relaxor ferroelectric behavior in the Ba1−xPbx(Ti1−yZry)O3 solid solutions

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Abstract Polycrystalline samples of Ba 1−x Pb x (Ti 1−y Zr y )O 3 (BPTZ) with x = 0.025 & 0.1 and 0.10 ≤ y ≤ 0.50 have been synthesized by high-temperature solid-state reaction technique. X-ray diffraction reveals the formation of single phase with tetragonal or cubic structure. Dielectric investigations were carried out in the temperature range from 80 to 445 K with frequencies range from 10 2 to 10 6  Hz. A broad dielectric anomaly coupled with the shift of dielectric maxima toward a higher temperature with increasing frequency indicates either a diffuse phase transition or relaxor behavior in some of these ceramics. Whatever lead content, when zirconium is substituted by titanium, T C and e’r max decreases while ΔT m(f)  = [T m (10 6  Hz)−T m (10 2  Hz)] and tgδ increase. The diffuse phase transition parameters were estimated from a linear fit of the modified Curie–Weiss law. A good fit to the Vogel–Fulcher relation further corroborates such a relaxor nature.