Enhanced strain and reduced dielectric loss in a bismuth-based high-TC ternary solid solution system of BiScO3-Pb(Sc1/2Nb1/2)O3-PbTiO3

Abstract

To design novel materials suitable for high-temperature electromechanical applications, a bismuth-based ternary solid solution system, (1-x-y)BiScO3-yPb(Sc1/2Nb1/2)O3-xPbTiO3, with compositions situated around the morphotropic phase boundary, were designed and synthesized in the form of ceramic. The crystal structure, microstructure, dielectric, ferroelectric and piezoelectric properties, and the local polar domain structure of the ceramics were investigated in detail. The examined ceramics exhibit large grain sizes ranging from 20 μm to 45 μm, along with noteworthy characteristics, including a relatively large strain of 0.21 %, a high large-signal piezoelectric coefficient (d33* = 368 pm/V), a low dielectric loss (tanδ = 1.7 %), and a high Curie temperature (TC ∼ 423 °C). These enhanced properties signify the suitability of the designed ternary ceramics for future high-temperature electromechanical applications. This work demonstrates an effective approach for designing ferro-/piezoelectric materials characterized by substantial strain and low dielectric loss.