Effect of lanthanum doping on electrical and electromechanical properties of Ba1−x La x TiO3

Abstract

The effect of lanthanum doping is studied on ferroelectric properties of Ba 1-x La x TiO 3 with x = 0⋅ ⋅0005, 0⋅ ⋅001, 0⋅ ⋅003 prepared through solid state sintering route. Dielectric and impedance spectroscopic studies have been carried out. The tetragonal distortion of the unit cell decreased and ferroelectric transition temperature, T c increased with the increase of lanthanum content. Combined impedance and admittance spectroscopy was used to analyse impedance data. The electromechanical parameters were calculated from the resonant and anti-resonant frequencies from vector admittance plots. The electromechanical coefficients for Ba 1-x La x TiO 3 with x = 0⋅ ⋅003 were found to be much larger than that of pure barium titanate.

Synthesis and electrical characterization of Ca2Nd4Ti6O20 ceramics

“…at 794.33 kHz, 1000 kHz and 1258.9 kHz for 744, 782 and 800°C, respectively. This is in accordance with the general principle that the capacitance decreases with increasing frequency [15,16]. R and C values were calculated from the peaks in the Z spectroscopic plots using f max value of the peak, i.e.…”

Properties of lanthanum doped BaTiO3 produced from nanopowders

“…The literature data mainly reports the preparation of lanthanum doped BT by solid state reaction [3][4][5][6]. Among the several soft chemistry routes that can be used, the polymeric precursor method has the advantage of assuring chemical purity of the final product what is very important for final properties of obtained material.…”

Electrical and structural characterization of PTCR pure BaTiO3 nanopowders synthesized by sol–gel emulsion technique

“…A critical size of the crystal lattice exists both, above and below which the crystal lose their polarizability due to which a decrease in permittivity is seen. It is clear from various studies that the permittivity of the material depends on the particle size [17,50,55,57]. Well investigated is the fact that PTCR is a grain boundary phenomenon [13,48,58,59].…”

“…6(b), with an increase in the dielectric constant, losses in the material also increased at 3 MHz frequency. Dielectric constant (ε r ) of a normal ferroelectric decreases with increasing frequency as it becomes difficult for the domains to change their orientation at the same rate as that of the electric field [55,56].…”