Crystalline structure, ferroelectric properties, and electrical conduction characteristics of W/Cr co-doped Bi4Ti3O12 ceramics

W/Cr co-doped BIT (BTWC) ceramics {Bi4Ti3-xWxO12+x + 0.25 wt% Cr2O3 (x = 0-0.1)} with a strong ferroelectricity and a high electrical resistivity were prepared by a conventional ceramic process, and effects of W doping content on their crystalline structures, ferroelectric properties and electrical conduction characteristics were also explored. By the co-doping of W/Cr, the crystallographic evolution happened in BTWC ceramics, and then the degree of the lattice distortion of BTWC ceramics decided on their spontaneous polarization and influenced their electrical resistivity. Moreover, both the increased applied field and measurement temperature can improve the P-r. The great improvement in remanent polarization and resistivity of BTWC ceramics were mainly attributed to the decreased concentration of oxygen vacancies by doping W6+. The Bi4Ti2.95W0.05O12.05 + 0.25 wt% Cr2O3 ceramic possessed a large P-r of 16 mu C/cm(2) and a high rho(dc) (600 degrees C) of 2.94 x 10(6) Omega cm, respectively, which makes it a promising candidate for high-temperature applications. (C) 2014 Elsevier B.V. All rights reserved.