Electrostrictive and relaxor ferroelectric behavior in BiAlO3-modified BaTiO3 lead-free ceramics

Abstract

The crystal structure of (1−x)BaTiO3-xBiAlO3 (x = 0, 0.02, 0.05, 0.08, and 0.1) ceramics was determined using X-ray diffraction and Raman spectroscopy at room temperature, which revealed a phase transition from tetragonal to rhombohedral with increasing x. The dielectric properties were studied as a function of temperature at different frequencies, which indicated that the phase transition temperature (Tm) decreased with increasing x. The relaxor behavior was observed by frequency and temperature dependent dielectric permittivity. The Lorenz-type quadratic law was used to characterize the dielectric permittivity peaks near Tm of high-temperature slopes at 1 MHz. The temperatures Tm of dielectric permittivity peaks fit very well with the Vogel-Fulcher law in x = 0.05 and x = 0.1. The polarization hysteresis loops and electrostrictive were displayed at room temperature. The sample for x = 0.1 exhibits a slim loop with negligible hysteresis and a subtle linear feature, which is a promising transducer material for use as an active element.

Thermally Stable BaTiO3‐Bi(Mg2/3Nb1/3)O3 Solid Solution with High Relative Permittivity in a Broad Temperature Usage Range

“…Modes 1 and 3 are related with A–O vibrations and their appearance suggests that there exists Ba 2+ or Bi 3+ cations enriched nano‐sized areas (clusters) . Similar spectral signatures associated with local cationic order have been already detected in BiAlO 3 ‐modified BT …”

Relaxor Behavior and Dielectric Properties of Bi(Zn2/3Nb1/3)O3-Modified BaTiO3 Ceramics

“…29 Similar spectral signatures associated with local cationic order have been already detected in BiAlO 3 -modified BT. 30 Figure 4 illustrates the SEM micrographs of (1 À x)BT-xBZN ceramics (x = 0.02, 0.06, 0.1 and 0.2) sintered at their optimized temperatures. All samples exhibit a dense structure with low porosity and the grain size is affected tremendously by the addition of BZN.…”

Oxygen vacancy-related dielectric relaxation and electrical conductivity in La-doped Ba(Zr0.9Ti0.1)O3 ceramics

“…Ba(Ti,Zr)O 3 based ceramics have been paid much attention for many decades due to their excellent dielectric, ferroelectric, electro-mechanical and piezoelectric properties [1,2]. Point defects, especially oxygen vacancy, play important role on their electrical properties [3], which often is produced during high-temperature sintering in the air [4].…”