Point defect engineering of high temperature piezoelectric BiScO3–PbTiO3 for high power operation

Abstract

BiScO3-PbTiO3 is used as a model system of BiMO3-PbTiO3 perovskite solid solutions with enhanced electromechanical response at ferroelectric morphotropic phase boundaries, and high Curie temperature to demonstrate specific point defect engineering for high power operation. The objective is to obtain a range of piezoelectric ceramics comparable to hard Pb(Zr,Ti)O3 materials, optimized for the different applications. In this work, a comprehensive study of Mn substitution for Sc is provided. Care is taken to isolate the effects of the point defects from those of concomitant structural and microstructural changes that have been previously described after MnO2 addition.Results strongly suggest that Mn substitution results in the formation of (MnSc'-VOcomplexes that effectively clamp domain walls. This is the same mechanism responsible of hardening in Pb(Zr,Ti)O3. Indeed, Bi0.36Pb0.64Sc0.36-x MnxTi0.64O3 with x=0.02 is shown to be a high sensitivity piezoelectric with strongly reduced losses, suitable for high power operation between 200 and 400 ºC.

Insights into the Performance of Magnetoelectric Ceramic Layered Composites

“…Figures of 440, 400, and 285 pC·N −1 were obtained for the materials SPS at 1000, 900, and 800 • C that had average grain sizes of 1.9, 0.9, and 0.35 µm, respectively. The value for the first material is comparable to those of ceramics sintered by conventional means from the same powder that have an average grain size of 2.4 µm, and from which all the ε 33 σ permittivity, the s 11 E and s 12 E compliances, and the d 31 piezoelectric coefficients have been reported [25]. Therefore, these permittivity and compliance values were assumed.…”

“…(1 − x) BiScO 3 -x PbTiO 3 is a perovskite solid solution with enhanced electromechanical response at a ferroelectric morphotropic phase boundary (MPB) located at x ≈ 0.64, which also has a high Curie temperature T C of ≈450 • C [24]. It is being extensively investigated as an alternative to state-of-the-art Pb(Zr,Ti)O 3 (PZT) for operation beyond 200 • C up to 400 • C [25,26]. Additionally, its properties present very good down-scaling behavior with grain size through the submicron scale [27], and even maintain functionality at the nanoscale [28].…”

“…Therefore, these permittivity and compliance values were assumed. [25,29], respectively. It is obvious that errors are being introduced by doing this, yet it is assumed that they are smaller than those associated with directly accepting the full set of material coefficients for the coarse-grained materials of [29], which also included MnO 2 as an additive to increase resistivity.…”

High‐temperature multilayer actuators based on CuO added BiScO3–PbTiO3 piezoceramics and Ag electrodes

“…Although these ceramics were just sintered at a relative low temperature of 900°C, these ceramics already show pure ABO 3 ‐type phase according to their XRD patterns shown in Figure A. Furthermore, the MPBs still exist in the BS‐PT: x CuO ( x = 0.1‐0.3wt%) ceramics since there are the splits of the tetragonal [002] T peak, the [200] T peak, and the rhombohedra [200] R peak in Figure B . However, only [002] T and [200] T peaks are left due to the pure tetragonal phase in the BS‐PT: x CuO ( x = 0.4 and 0.5wt%) ceramics.…”

“…It is noted that the morphotropic phase boundaries (MPBs) of (1− x )BiScO 3 ‐ x PbTiO 3 ceramic are always at x ~0.63 at 20‐450°C which is an essential factor to achieve the commercial piezoelectric ceramics with high piezoelectric stability during the temperature changing process . Furthermore, the 0.367BiScO 3 –0.633PbTiO 3 (BS‐PT) ceramic shows excellent piezoelectric and electromechanical properties (eg, piezoelectric coefficient d 33 > 450 pC/N and electromechanical coupling factor k p ~ 0.56) …”