Domain wall contribution to dielectric and piezoelectric responses in 0.65Pb(Mg_1/3Nb_2/3)–0.35PbTiO₃ferroelectric ceramics

Abstract

In this paper, the contribution of the domain walls motion to the dielectric and piezoelectric responses for the 0.65Pb(Mg1/3Nb2/3)O3–0.35PbTiO3 system is investigated. A monotonically increasing temperature dependence of the dielectric permittivity is observed from very low temperatures up to the ferroelectric–paraelectric phase transition temperature. It is verified that the major contribution to dielectric response at room temperature is from the extrinsic effect. A linear dependence of the permittivity with the amplitude of the ac applied electric field is verified from the nonlinear dielectric measurement. Rayleigh's model is used to quantitatively evaluate the dielectric response, leading to similar behaviour of the typical soft PZT. On the other hand, direct piezoelectric response also displays a Rayleigh-type behaviour. Piezoelectric measurements show in the entire investigated dynamic stress range a decrease in the piezoelectric response with both increase in frequency of the applied dynamic stress and increase in the pre-stress on the samples.

Effect of Mn-acceptor dopant on dielectric and piezoelectric responses of lead lanthanum zirconate titanate piezoceramics

“…The Rayleigh model has been frequently and satisfactorily used to evaluate the nonlinear dielectric and piezoelectric responses in several ferroelectric ceramics. 14,16,19,[23][24][25][26][27][28][29] This model assumes that the response R of a piezoelectric material can be described by the following relation:…”

“…13 One of the disadvantages of using soft PZT is its high nonlinear behavior, which is expressed as a strong dependence on the permittivity and the piezoelectric coefficient with the strength of the ac electric field or the mechanical stress that are applied. [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29] However, in a hard PZT, the nonlinear response is weak, due to the decrease of the mobility of the domain walls. The addition of acceptor ions leads to the creation of complex defects, which act as pinning centers for the domain walls.…”

Extrinsic Contribution and Instability Properties in Lead-Based and Lead-Free Piezoceramics

“…At each temperature, the interval of applied field amplitudes is the same in all cases. As can be observed, there is a linear relation between the real and imaginary parts of the permittivity, which is a common characteristic that has been reported for a wide number of piezoceramics [26,27,29,30,43], even when Δε′ and Δε″ do not depend linearly on the field amplitude. Two features may be highlighted in the Δε″ versus Δε′ graph: the distance between two adjacent points of a plot and the slope of the plot.…”

“…In contrast, the extrinsic contribution related to domain wall motion is markedly temperature-dependent. The motion of the domain walls is thermally assisted, and is generally the main contribution to material response at room temperature [6,29,30,31,32]. Consequently, only intrinsic response is expected at very low temperature as a result of the domain wall freezing phenomenon [33].…”

“…Since the dielectric and piezoelectric properties of piezoceramics are strongly determined by the ferroelectric/ferroelastic domain structure and the dynamics of the domain walls [23], the nonlinear response will depend on any microstructural aspect that modifies the domain structure and/or the domain wall motion, such as the crystallographic phase, the grain size, and the compositional modifications by doping. The microstructural dependence of nonlinear response has been widely studied in PZT [24,25,26,27] and other ceramic systems such as barium titanate (BT) [28], lead magnesium niobate—lead titanate (PMN-PT) [29], and potassium sodium niobate (KNN) [30]. This review focuses on the role of the ferroelectric domain wall motion/dynamics in the nonlinear response in the most workable lead-based and lead-free piezoelectric ceramics with a perovskite structure.…”