Abstract

Polycrystalline solid solutions of [Pb 1-x-yBa xSr y][Zr zTi 1-z] 1-(5k/4)-(m/2)Nb kZn mO 3 (PBSZZNT) substituted as [Pb 0.973Ba 0.015Sr 0.012][Zr 0.53Ti 0.47] 0.975-(m/2)Nb 0.02Zn mO 3 where m = 0, 0.5, 1.0 and 1.5 mol% have been synthesized through a solid-state reaction method and their dielectric and ferroelectric properties were investigated. X-ray diffraction patterns indicated that all compositions exhibit a single ferroelectric tetragonal phase (FE TET). The average grain growth increased to 1 mol% Zn (2.42 μm) while the density was promoted up to 1.5 mol% Zn (7.74 gm/cm 3) doped PBSZNT ceramics, respectively. Dielectric studies reveal that the room-temperature dielectric constant (ε RT) decreased constantly while the Curie temperature (T c) showed mixed behavior in Zn-doped PBSZNT ceramics, respectively. The optimum ferroelectric properties were observed in 1 mol% Zn doped PBSZNT where both A-site and B-site modification was evidently enhanced (P r = 33.12 μC/cm 2 and P s = 39.86 μC/cm 2) with relatively decreasing coercive field. The influence of Zn-modified compositions on the Ti-rich region (Zr/Ti = 53/47) in PBSZNT ceramics showed significant variations that are discussed. © 2007 WILEY-VCH Verlag GmbH & Co. KGaA.