Abstract

[Pb 0.961La 0.012Ba 0.015 Sr 0.012][Zr 0.53Ti 0.47] 0.967-(h/2)Nb 0.02Zn 0.01 Mn hO 3 (PLBSZZMNT) nano-ceramics where h = 0, 0.5. 1 and 1.5 mol% fabricated through solid state reaction method has been investigated for phase formation, microstructure, density, dielectric and piezoelectric properties. X-ray diffraction studies indicated that all the samples exhibited a single-phase perovskite tetragonal structure which had strongly intensified due to the acceptor Mn content increment in the series. Our investigation with reference to isovalent (Ba 2+ and Sr 2+) on the A-site, pentavalent donor (Nb 5+) and acceptor (Zn 2+ and Mn 4+) dopants on the B-site in PLZT perovskite with the stoichiometric compositional formulation tailored for dielectric and piezoelectric properties has been clearly explained. As Mn concentration increased, the grain growth enhanced, and the inter-diffusion between multiple ions promoted densification in the PLBSZZMNT nano-ceramics. TEM studies revealed an average particle size ranging from 20 to 72 nm. Dielectric characterization revealed that the ε RT enhanced till 1.5 mol% Mn (2946) while the Curie temperature and dielectric loss at room temperature (T c and Tanδ RT) decreased, respectively. Mn doping in PLBSZZNT induced the piezoelectric parameters (k p = 0.567) and (d 33 = 486 pC/N) till 1.5 mol% Mn. Thus, 1.5 mol% Mn modified PLBSZZNT exhibits optimum dielectric and piezoelectric properties, which are suitable for possible sensor and actuator applications. © Springer Science+Business Media, LLC 2007.