The influence of A-site strontium ion in controlling the microstructure and electrical properties of P1−<i>x</i>S<i>x</i>ZNZT ceramics

Abstract

A Pb1−xSrx(Zn1/3Nb2/3)0.2(Zr0.5Ti0.5)0.8O3 (P1−xSxZNZT, 0.00 ≤ x ≤ 0.10) system was prepared through a conventional solid oxide process. Increasing addition of Sr2+ was found to induce a continuous decrease in grain size from 2.46 μm to 1.14 μm, accompanied by a phase transformation from coexisting rhombohedral and tetragonal phases to tetragonal phase only. The underlying mechanism of the evolution of dielectric and ferroelectric behavior in the P1−xSxZNZT ferroelectric ceramics was ascribed to the synergy between the grain size effect and the dilution of Pb-O covalency. Additionally, the grain size effect on domain wall displacement was found to be the main origin of the superior permittivity and piezoelectricity of the ceramics at intermediate grain size. The optimal electrical properties achieved for the P0.95S0.05ZNZT specimen at a grain size of about 1.79 μm, d33 = 465 pC/N, d33 × g33 = 11 047 × 10−15 m2/N make this material promising for multilayer energy harvesting device applications.