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The structure and electric properties of (0.9-x)Bi(Mg1/2Ti1/2)O3-xPbTiO3-0.1BaZrO3 (0.45 ≤ x ≤ 0.53) ceramics were investigated. The morphotropic phase boundary between tetragonal ferroelectric and pseudo-cubic relaxor phases is ascertained at x = 0.50. The BaZrO3 substitution can much reduce the coercive field of Bi(Mg1/2Ti1/2)O3-PbTiO3. The studies on temperature dependence of both ferroelectric and dielectric constant indicate a direct evidence for the antiferroelectric relaxor phase, which was ever suggested in the binary system of Bi(Mg1/2Ti1/2)O3-PbTiO3. The phase transition of ferroelectric to antiferroelectric relaxor produces the thermal depoling below the Curie temperature. The ceramic of BMT-0.47PT-0.1BZ exhibits a high strain 0.37% and a large-signal d33 (530 pm/V) in the antiferroelectric-relaxor phase. BaZrO3 substituted Bi(Mg1/2Ti1/2)O3-PbTiO3 shows an analogous phase diagram to that of lead-free (Bi, Na)TiO3-BaTiO3. [ABSTRACT FROM AUTHOR]

Single-phase xNdFeO3–(1 −x)PbTiO3 thin films with different dopant contents were fabricated on the Pt(111)/Ti/SiO2/Si substrate by a sol–gel route. Grain size was influenced by the dopant content effectively. A synchrotron radiation X-ray diffraction study revealed a reduced tetragonality (c/a) of the PbTiO3 lattice in the films. Distortion of the TiO6 octahedron was weakened, as investigated by Raman scattering and X-ray absorption spectra. An electronic structural study indicated that the hybridizations between O 2p and Pb 6s and Ti 3d orbitals were weakened. The decrease of lattice distortion and orbital hybridization gives rise to degradation of the ferroelectric nature in the films. [ABSTRACT FROM AUTHOR]

Ferroelectric property stability against elevated temperature is significant for ferroelectric film applications, such as non-volatile ferroelectric random access memories. The high-TC 0.2Bi(Mg1/2Ti1/2)O3-0.8PbTiO3 thin films show the temperature-independent ferroelectric properties, which were fabricated on Pt(111)/Ti/SiO2/Si substrates via sol-gel method. The present thin films were well crystallized in a phase-pure perovskite structure with a high (100) orientation and uniform texture. A remanent polarization (2Pr) of 77 μC cm-2 and a local effective piezoelectric coefficient d33* of 60 pm/V were observed in the 0.2Bi(Mg1/2Ti1/2)O3-0.8PbTiO3 thin films. It is interesting to observe a behavior of temperature-independent ferroelectric property in the temperature range of room temperature to 125 °C. The remanent polarization, coercive field, and polarization at the maximum field are almost constant in the investigated temperature range. Furthermore, the dielectric loss and fatigue properties of 0.2Bi(Mg1/2Ti1/2)O3-0.8PbTiO3 thin films have been effectively improved by the Mn-doping. [ABSTRACT FROM AUTHOR]

Abstract: 0.96(Na,K)(Nb0.9Ta0.1)O3–0.04LiSbO3 powders in the orthorhombic phase were synthesized in the molten salt KCl at a low temperature 800°C. It was revealed that K+ in the molten salt tended to substitute Na+ in the A-sites and the final product 0.96(Na0.29K0.71)(Nb0.9Ta0.1)O3–0.04LiSbO3 was synthesized from the nominal composition 0.96(Na0.5K0.5)(Nb0.9Ta0.1)O3–0.04LiSbO3. The dense ceramics under pressureless were obtained by sintering in the air. The ceramics exhibited high piezoelectric constant d 33 of 239pC/N and good remnant polarization P r of 30.79μC/cm2 with coercive electric field E c of 2.01kV/mm. And leakage current was reduced by muffling the ceramics with the as-prepared powders during the sintering process. [Copyright &y& Elsevier]

Abstract: According to consideration on the average radius of B-site cation of BiMeO3, we reported that the Bi(Mg0.5Zr0.5)O3–xPbTiO3 compound at the morphotropic phase boundary (MPB) of x=0.58 possesses a piezoelectric coefficient d 33 as high as 306pC/N. The optimal piezoelectric and ferroelectric properties near the MPB might be attributed to its lower lattice distortion, as described by change of FWHM value for {111}PC peaks. Furthermore, Bi(Mg0.5Zr0.5)O3–xPbTiO3 displayed stable ferroelectric and piezoelectric properties over a temperature range from ambient temperature to above 160°C, as exhibited by temperature dependence polarization and strain versus electric field curves and thermal depoling process. [Copyright &y& Elsevier]