Structural stability and depolarization of manganese-doped (Bi0.5Na0.5)1−xBaxTiO3 relaxor ferroelectrics

Abstract

This work reveals that 0.5 mol. % manganese (Mn) doping in (Bi0.5Na0.5)1−xBaxTiO3 (x = 0 and 0.075) solid solutions can increase structural thermal stability, depolarization temperature (Td), piezoelectric coefficient (d33), and electromechanical coupling factor (kt). High-resolution X-ray diffraction and transmission electron microscopy reveal coexistence of rhombohedral (R) R3c and tetragonal (T) P4bm phases in (Bi0.5Na0.5)0.925Ba0.075TiO3 (BN7.5BT) and 0.5 mol. % Mn-doped BN7.5BT (BN7.5BT-0.5Mn). (Bi0.5Na0.5)TiO3 (BNT) and BN7.5BT show an R − R + T phase transition, which does not occur in 0.5 mol. % Mn-doped BNT (BNT-0.5Mn) and BN7.5BT-0.5Mn. Dielectric permittivity (ε′) follows the Curie-Weiss equation, ε′ = C/(T − To), above the Burns temperature (TB), below which polar nanoregions begin to develop. The direct piezoelectric coefficient (d33) and electromechanical coupling factor (kt) of BN7.5BT-0.5Mn reach 190 pC/N and 47%.

Enhanced ferroelectric properties and thermal stability of Mn‐doped 0.96(Bi0.5 Na0.5)TiO3‐0.04BiAlO3 ceramics

“…There are several methods to determine the T d in the literatures, whereas for the same material the T d value obtained through different measuring methods have a correlation but apparent disparity up to 30°C . The TSDC is a highly recommendable method for T d measurement with technically viable necessitating furnace and electrometer .…”

“…, reported that the composite of 0.94BNT–0.06BT and ZnO possessed excellent piezoelectric properties as well as elevated temperature stability . Studies also suggested that Mn doping in BNT and 0.925BNT–0.075BT ceramics improved electrical properties and thermal stability . Zhu et al.…”

Effects of seed layer and crystallization process on crystal orientation and properties of NKBT thin films

“…A little lattice mismatch between PLCT and NKBT makes the peak splitting on (100) and (200). All the samples show broadened (200) peaks, which can be assumed a variety of ferroelectric phases indicating that this film may be close to the morphotropic phase boundary (MPB) [17]. Benefiting from the MPB effect, superior piezoelectric performance can be expected [18].…”

Dielectric properties of Bi-Doped BaTiO3-based ceramics synthesized by liquid-state method

“…Generally, nano-sized BaTiO 3 -based powder is usually prepared via wet chemical method such as the precipitation method [5,6], the sol-gel press [7], and traditional solid-state method [8][9][10][11][12]. In general, a traditional solid-state method is used to prepare MLCCs ceramics.…”

“…The core is doped with some elements to increasing the Curie point so that achieving better temperature stability. Among such dopants, the bismuth has a signifi cant effect on the fabrication of MLCCs [19,20].…”