Formation mechanism of highly [0 0 1]c textured Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 relaxor ferroelectric ceramics with giant piezoelectricity

Abstract

We investigated the synthesis mechanism and giant piezoelectricity of highly [001]c textured Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 (PIN-PMN-PT) relaxor based ferroelectric ceramics (texture fraction ∼94%) with BaTiO3 (BT) templates. The onset of texture occurred at ∼88% relative density (RD), and rapid increase in texture fraction happened with RD>94%. A PbO-rich grain boundary liquid of ∼6–13nm thickness, detected at oriented crystalline interfaces, facilitated epitaxial nucleation and subsequent [001]PIN-PMN-PT||[001]BT growth of textured grains on BT templates. Interfaces between BT templates and PIN-PMN-PT textured grains were found to be coherent and defect-free at the atomic scale, and there was almost no barium diffusion across the interfaces during the texturing process. Nanodomains were clearly visible in the oriented grains. [001]c poling ordered the domain structures of textured ceramics and resulted in a more uniform domain size of several hundred nanometers. The textured ternary PIN-PMN-PT ceramics exhibited ∼200% improvement in piezoelectric response relative to their random counterparts, as a result of their piezoelectric anisotropy and engineered domain status along with higher mobility of domain walls.