Structure and dielectric properties of (1-x)Bi0.5Na0.5TiO3–xBaTiO3 piezoceramics prepared using hydrothermally synthesized powders. Issue 7 (28th July 2021)

• Record Type: Journal Article
• Authors: Nesterović, Andrea; Vukmirović, Jelena; Stijepović, Ivan; Milanović, Marija; Bajac, Branimir; Tóth, Elvira; Cvejić, Željka; Srdić, Vladimir V.
• Is Part Of: Royal Society open science. Volume 8:Issue 7(2021)
• Publication Date: 2021-07-28
• Subjects: BNT-BT -- hydrothermal synthesis -- sintering -- perovskite -- dielectric properties; Science -- Periodicals; 500
• DOI: 10.1098/rsos.202365
• Languages: English
• ISSNs: 2054-5703

Abstract

Abstract : The influence of different processing parameters and various Ba 2+ addition (up to 10 mol%) on the structure and dielectric properties of Bi0.5 Na0.5 TiO3 -BaTiO3 (BNT-BT) ceramics was investigated. The powders were hydrothermally synthesized in the alkaline environment at 180°C for different time periods. X-ray diffraction confirmed the presence of dominant rhombohedral Bi0.5 Na0.5 TiO3 phase and a small amount of secondary pyrochlore Bi2 Ti2 O7 phase in the pure BNT powders. In addition, one-dimensional Na2 Ti2 O7 structure was also observed in the powder hydrothermally treated for a long time (i.e. 48 h). The amount of secondary pyrochlore phase in the BNT-BT powders increases with the increase of Ba 2+ content. The synthesized powders were pressed into pellets and finally sintered at various temperatures up to 1150°C. High density (more than 90%TD) was obtained in all BNT-BT sintered samples. Optimal sintering parameters were chosen in order to obtain dense ceramics with the optimal phase composition. The temperature dependence of dielectric properties for the BNT-BT ceramics was also studied. Relaxor behaviour of BNT-based ceramics and broad transition peaks are evident in all samples. Dielectric constant up to 400 as well as an acceptable low dielectric loss at temperatures lower than 200°C were obtained in BNT-BT ceramics.