Orthorhombic-tetragonal phase coexistence and enhanced piezo-response at room temperature in Zr, Sn, and Hf modified BaTiO3

Abstract

The effect of Zr, Hf, and Sn in BaTiO3 has been investigated at close composition intervals in the dilute concentration limit. Detailed structural analysis by x-ray and neutron powder diffraction revealed that merely 2 mol. % of Zr, Sn, and Hf stabilizes a coexistence of orthorhombic (Amm2) and tetragonal (P4mm) phases at room temperature. As a consequence, all the three systems show substantial enhancement in the longitudinal piezoelectric coefficient (d33), with Sn modification exhibiting the highest value ∼425 pC/N.

Enhanced temperature stability and quality factor with Hf substitution for Sn and MnO2 doping of (Ba0.97Ca0.03)(Ti0.96Sn0.04)O3 lead-free piezoelectric ceramics with high Curie temperature

“…However, the effect of Hf for increasing T O-T and T R-O at the B-site of BaTiO 3 ceramics is more obvious than that of Sn addition. 26 It can be explained that an increase of T C and T O-T , slight increase of T R-O with substituting Hf for Sn in our work. Additionally, the overall dielectric constant decreases, and the grain size becomes smaller with increasing x.…”

Phase evolution and enhanced electrical properties of (Ba0.85Ca0.15−x Y x )(Zr0.1Ti0.9)O3 lead-free ceramics

“…T), there is an increased number of directions along which spontaneous polarization can be oriented. Free energies of the two phases coexisted are similar so that spontaneous polarization can be switched easily among these different directions [25].…”

“…Lead-free piezoelectric ceramics have attracted much attention due to their non-toxicity in nature and comparable piezoelectric properties with the popular Pb(Zr,Ti)O 3 ceramics [1,2]. Among many lead-free piezoelectric ceramics, Ba(Zr 0.2 Ti 0.8 )O 3 -x(Ba 0.7 Ca 0.3 )TiO 3 (abbreviated as BCT-xBZT) ceramics system has obtained significant attention in recent years due to its high piezoelectric response (piezoelectric constant d 33 = 620 pC/N) [3].…”

Giant Electrostrictive Responses and Temperature Insensitive Strain in Barium Titanate‐Based Ceramics

“…[2] Nevertheless, some issues still limit the practical applications of BaTiO 3based ceramics, including low Curie temperature (T C ), poor temperature stability, etc. [5][6][7] Although some advances in structure and property were achieved, some shortcomings still limit the developments of BT-based ceramics. [5][6][7] Although some advances in structure and property were achieved, some shortcomings still limit the developments of BT-based ceramics.…”

“…[14] Previously, the best electrostrictive materials are well known as Pb(Mg 1/3 Nb 2/3 )O 3 (PMN) relaxors with a large electrostrictive coefficient Q 33 of 0.02 m 4 C −2 . [2,6] Based on above discussions, we want to realize the temperature-insensitive strain and the enhanced electrostrictive effect along with increasing T C by developing the material system of 0.95BaTiO 3 -0.05(M 0.5 N 0.5 )TiO 3 (M = K/Na/Li and N = Ho, Y, Yb, Ga, Nd, Pr, Sm, Gd). [9,11,12] On the other hand, some efforts have been employed to not only improve the electrical properties but also increase the T C of BT-based ceramics by chemical modifications, [16,17] and unfortunately most of the additives deteriorated the T C of BT-based ceramics, such as La, Gd, Sr doping in A-site [18][19][20] or Zr, Sn, Hf doping in B-site.…”