Crystal Structure, Microstructure, Piezoelectric and Dielectric Properties of Piezoceramic Bi7Sr2TiNb5O27

A new layered perovskite-like oxide Bi7Sr2TiNb5O27 was synthesized by the method of high-temperature solid-state reaction, in which partial substitution of bismuth (Sr2+) atoms in the dodecahedra of the perovskite layer (A-positions) by Bi3+ ion took place. X-ray structural studies have shown that compound was single-phase and had the structure of Aurivillius-Smolensky phases (ASPs) with close parameters of orthorhombic unit cell, corresponding to space group A21am. The dependence of the relative permittivity ε/ε0, the tangent of loss tan σ at different frequencies on temperature and piezoelectric constant d33 were measured.