Microstructure and texture dependence of the dielectric anomalies and dc conductivity of Bi3TiNbO9 ferroelectric ceramics

Abstract

Ceramics of composition Bi 3 TiNbO 9 ͑BTN͒ and perovskite-layered structure ͑Aurivillius type͒ ͓B. Aurivillius, Ark. Kemi 1, 463 ͑1949͔͒ were processed by natural sintering and hot pressing from amorphous precursors. Precursors were obtained by mechanochemical activation of stoichiometric mixtures of oxides. These materials are in general interesting for their use as high-temperature piezoelectrics. Among them, BTN possesses the highest ferroparaelectric phase-transition temperature ͑Ͼ900°C͒. The transition temperature establishes the working limit of the ceramic and the electric properties, especially the dc conductivity, affect on its polarizability. In this work, dielectric studies of BTN ceramics with controlled texture and microstructure have been made at 1, 100 KHz, and 1 MHZ and in the temperature range from 200°C up to the ferroparaelectric transition temperature. Values of Јϳ 250 at 200°C are achieved in ceramics hot pressed at temperatures as low as 700°C for 1 h.

Structural and Electrical Properties of W6+‐Doped Bi3TiNbO9 High‐Temperature Piezoceramics

“…The resistivity of BTNO is only about 10 7 Ω·cm below 400°C, 9 for example. Most of the studies reported on BTNO have concentrated on the crystal structure, 3,8,10,11 synthesis, and electrical properties of pure bulk BTNO ceramics, 12–15 Other studies have focused on the properties of intergrowth compounds such as (Bi 3 TiNbO 9 ) x (SrBi 2 Nb 2 O 9 ) 1− x 16 and (Bi 3 TiNbO 9 ) x (Bi 4 Ti 3 O 12 ) 1− x 17 . Only a few works have addressed the properties of cation‐modified BTNO‐based ceramics.…”

Textured Ca0.85(Li,Ce)0.15Bi4Ti4O15 ceramics for high temperature piezoelectric applications

“…In order to enhance the piezoelectric properties, A and B site modification are commonly used [5][6][7][8]. Texturing technologies, such as hot-forging [9], hot-pressing [10], spark plasma sintering (SPS) [11] and tape casting [12] is another way to improve the piezoelectric properties of Aurivillius type ceramics. CaBi 4 Ti 4 O 15 (CBT) is a member of Aurivillius family with high Curie temperature (T c = 790 8C) and low dielectric loss.…”

Doping level effects in Nb self‐doped Bi3TiNbO9 high‐temperature piezoceramics with improved electrical properties

“…However, the lower piezoelectric coefficient (d 33 ) which is restricted by the two-dimensional rotation of the polarization orientation and the high coercive fields (E c ) has greatly restricted their applications. [5][6][7][8][9][10] Bismuth titanate niobate (Bi 3 TiNbO 9 , NBT), a member belonging to the BLSFs, possessing a very high T C (~913°C), is deemed as one of the rare candidates that can be utilized at temperatures above 600°C. However, similar to other BLSFs ceramics, the pristine NBT exhibits a very low d 33 (<7 pC/N) and relatively low resistivity (6.90 × 10 4 Ω•cm at 600°C).…”

“…However, similar to other BLSFs ceramics, the pristine NBT exhibits a very low d 33 (<7 pC/N) and relatively low resistivity (6.90 × 10 4 Ω•cm at 600°C). 9,10 Great efforts need to be paid to realize its practical application.…”