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Influence of A-site doping with Li+, Ag+, and K+ cations on structure, microstructure, dielectric, ferroelectric, and local piezoelectric properties of potassium niobate (K0.5Na0.5)NbO3 ceramics wa...

The effect of substitution of lithium cations in the sublattice A of sodium bismuth titanate on the parameters of the crystal structure, microstructure, dielectric and local piezoelectric propertie...

Influence of cation substitutions in (K0.5Na0.5)NbO3–Ba(Li2/5W3/5)O3 ceramics on structure parameters, microstructure, dielectric, ferroelectric and local piezoelectric properties have been studied...

We have prepared (1 – x)(K0.5Na0.5)NbO3–xCa(Cu1/3Nb2/3)O3 (x = 0–0.1, ∆х = 0.02) ceramics by solid-state reactions and studied their phase formation, structure, and dielectric and ferroelectric properties. The formation of a phase with the perovskite structure and an orthorhombic unit cell has been demonstrated in all of the samples. Ferroelectric phase transitions have been confirmed by dielectric spectroscopy and laser second harmonic generation measurements. The temperatures of the phase transitions from the orthorhombic ferroelectric phase to the tetragonal ferroelectric phase and to the cubic (paraelectric) phase have been shown to decrease with increasing x. We have analyzed the composition dependences of dielectric parameters in the system studied.

Single-phase ceramic samples with the perovskite structure [(Na0.5Bi0.5)1 – xKx] TiO3 (x = 0, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06) are prepared by the method of solid-state synthesis and their structure, microstructure and dielectric and ferroelectric properties are studied. An increase in the unit-cell parameters of the perovskite lattice as a result of an increase in the K-cation content in accordance with the ratio of the radii of cations in the A sublattice of the perovskite structure is proved. The method of second-harmonic generation confirms that the introduction of potassium cations in the A positions of the perovskite lattice promotes enhancement of the ferroelectric properties of the studied samples. Dielectric-relaxation effects are revealed, which indicate the presence of vacancies in the oxygen sublattice.

Effects of cation substitutions on crystal structure parameters, microstructure, dielectric and ferroelectric properties of ceramic solid solutions (Na0.5Bi0.5)(Ti1-xMgx)O3 with x = 0 ÷ 0.1 were st...

Structure, microstructure, dielectric, ferroelectric, and local piezoelectric properties of perovskite ceramics in the systems (1-x)(K0.5Na0.5)NbO3 – x(Bi0.5Na0.5)TiO3 (x = 0 ÷ 0.1) and (1-x)(K0.5N...

The influence of LiSbO3 on the structure, microstructure, dielectric, ferroelectric and local piezoelectric properties of (K0.5Na0.5)NbO3 ceramics has been studied. Changes in unit cell parameters correlated with ionic radii changes and high effective local d33 piezoelectric coefficient values were observed depending on solid solutions compositions.

We have studied the effect of A-site cation substitutions in sodium bismuth titanate on the structural parameters, microstructure, and dielectric and ferroelectric properties of [(Na0.5Bi0.5)1 –xAx]TiO3 (A = La3+, x = 0–0.1) ceramics, including those modified with KCl additions. The samples have been shown to undergo phase transitions, which show up as anomalies in dielectric permittivity near ~400 K and peaks at ~600 K. The phase transitions near 400 K exhibit well-defined relaxor behavior, indicative of the presence of polar regions in a nonpolar matrix, as supported by laser second harmonic generation measurements.

Influence of overstoichiometric KCl additives on structure parameters, microstructure, dielectric, and ferroelectric properties of (K0.5Na0.5)NbO3 – LiNbO3 ceramics have been studied. Chang...

The effect of modification (in the А and В sublattices) on the crystal structure parameters, microstructure, and dielectric and local piezoelectric properties of perovskite ceramics (1 – x)(K0.5Na0.5)NbO3–xLa(Ag0.5Sb0.5)O3 was studied. At increased concentration of the second component, the lattice volume and average grain diameter decreased, and the temperature of the polymorphic transition and Curie temperature lowered. The dielectric and effective piezoelectric properties of the samples were found to depend nonmonotonically on the composition, average grain diameter, and degree of texturing of the ceramics.

Influence of cation substitution on structure parameters, microstructure, dielectric, ferroelectric and local piezoelectric properties of (K0.5Na0.5)NbO3 ceramics additionally modified by Li+ and M...

Effects of cation nonstoichiomtry on crystal structure parameters, microstructure, and dielectric properties of ceramics (Na0.5+xBi0.5)TiO3and (Na0.5-xBi0.5)TiO3with Bi/Na0.5Bi0.5)1-xKx]TiO3and (Na0.5Bi0.5)(Ti1-xMgx)O3withx= 0 – 0.1 have been studied. Changes in the unit cell parameters and microstructure of the samples observed in ceramics prepared correlate well with both preparation conditions and radii of substituting cations. Ferroelectric phase transitions near ~ 400 K and ~ 600 K were confirmed ib the systems studied. Phase transitions near ~ 400 K demonstrate a pronounced relaxor behavior determined by the presence of polar regions in a nonpolar matrix. Besides, additional anomalies related to presence of relaxing dipoles formed by oxygen vacancies were observed on temperature dependences of dielectric permittivity at temperatures higher than 700 K. The results obtained confirmed that increase in nonstoichiometry lead to increase in ionic conductivity of the samples.

Phase formation, crystal structure, microstructure, dielectric, ferroelectric and relaxor properties of nonstoichiometric ceramics (Na0.5+xBi0.5)TiO3 and (Na0.5Bi0.5-x)TiO3 with ratio Na/Bi>1, (Na0.5-xBi0.5)TiO3 and (Na0.5Bi0.5+x)TiO3 with ratio Na/Bi < 1 and x = 0 – 0.1 have been studied. Anomalies near 400 K and peaks at ∼ 600 K corresponding to ferroelectric phase transitions were revealed on temperature dependences of dielectric permittivity. Phase transitions near 400 K demonstrate a pronounced relaxor behavior determined by the presence of polar regions in a nonpolar matrix. It is shown that increase in the Na/Bi ratio in ceramics I and II contributes to improvement of their dielectric and ferroelectric properties.

Influence of various over stoichiometric additives on phase formation, unit cell parameters, microstructure, dielectric and ferroelectric properties of solid solutions 0.8[0.8(Na0.5Bi0.5)TiO3-0.2BaTiO3]-0.2Bi(Mg0.5Ti0.5)O3 system has been studied.The unit cell volume slightly decreased in case of the V2O5 additives but did not change in case of Bi2O3, LiF, and KCl additives. Increase in dielectric parameters ert and tanδrt values at the room temperature was revealed for compositions doped by KCl additives, while these parameters decreased in compositions doped by the V2O5 additives. Linear correlation between piezoelectric coefficient d33 measured for separate grains using the Piezoresponse Force Microscopy method and dielectric permittivity ert values at the room temperature was confirmed.

We have studied the phase formation, microstructure, and dielectric and ferroelectric properties of (Na0.5–xBi0.5)TiO3 and (Na0.5Bi0.5 + x)TiO3 nonstoichiometric ceramics with Na/Bi 0.05 have anomalies near 900 K, confirming the presence of Bi4Ti3O12 as an impurity phase, which is accompanied by an increase in the spontaneous polarization of these samples.

The phase formation, structural features, and dielectric, ferroelectric, and piezoelectric properties of ceramics with compositions from the region of the morphotropic phase boundary in the (Na0.5Bi0.5)TiO3–BaTiO3–Bi(Mg0.5Ti0.5)O3 system modified by different low-melting additives (Bi2O3, V2O5, KCl, NaCl–LiF, LiF, CuO, and MnO2) are studied. First-order phase transitions are detected near 700–800 and 400 K that display relaxor behavior and are indicative of the presence of polar regions in a nonpolar matrix. Prospects for improving the piezoelectric properties of the modified ceramic samples are confirmed.

A review is presented of the synthesis and complex investigation of modified ion-conducting ceramics based on heterosubstituted lanthanum gallate as a promising electrolyte material for solid oxide fuel cells. The effect the composition of multicomponent complex oxides has on the structure, microstructure, and electrophysical properties of ceramics is examined. Samples of ceramics with new compositions are produced via solid-state synthesis and modified with lithium fluoride. A drop is observed in the sintering temperature of the ceramics, caused by the liquid phase mechanism of sintering as a result of the low-melting superstoichiometric quantities of the additive. The effect lithium fluoride has on the process of phase formation, microstructure, and conductivity of the ceramics is investigated. It is found that samples modified with lithium fluoride display high density, dense grain packing, and high values of electrical conductivity at high temperatures.

The solid-phase synthesis method is used to prepare perovskite-like ceramic samples with the compositions (La0.8Sr0.2){[Ga0.8–x(Si0.5Mg0.5) x ]Mg0.2}O3–y (x = 0, 0.1, 0.2, 0.4, and 0.6) and investigate their phase formation, structure, microstructure, and electrical conductivity. Single-phase samples are obtained when up to 10 at % of gallium cations are replaced with silicon and magnesium cations. It is established that silicon-containing samples with the perovskite structure are characterized by a high density, optimal microstructure, dense grain packing, and large electrical conductivities at high temperatures.

Features are studied of the phase formation, structural parameters, microstructure, and dielectric and ferroelectric properties of non-stoichiometric (Na0.5 + xBi0.5)TiO3 ceramics with x = 0–0.1. The investigated samples exhibit ferroelectric phase-transition behavior as anomalies and peaks in dielectric permittivity near 400 and 600 K, respectively. Study of the second harmonic generation shows that phase transitions near 400 K exhibit relaxor-type behavior, indicating there are polar regions in the nonpolar matrix. An increase in the Na/Bi ratio in the initial compositions improves the dielectric and ferroelectric properties of the ceramics.

Single-phase ceramic samples from the region of morphotropic phase boundary in the (1–x)(Na0.5Bi0.5)TiO3–xBaTiO3 and (1–y)[(Na0.5Bi0.5)TiO3–xBaTiO3]–yBi(Mg0.5Ti0.5)O3 systems, modified by low-melting LiF and 0.6NaCl–0.4LiF additives, have been prepared by solid-state synthesis. The effect of additives on the phase formation, structural parameters, and dielectric and ferroelectric properties of the ceramics has been studied. A decrease in the ceramic sintering temperature is found. A slight increase in the unit-cell volume upon modification of the ceramics under study by lithium fluoride and 0.6NaCl–0.4LiF additive is revealed. First-order ferroelectric phase transitions near 700–800 K have been observed. The prospects for improving the piezoelectric properties of modified ceramic samples are proved.

The phase formation, specific features, and the dielectric properties of the ceramics of compositions from the region of morphotropic interface in the (Na0.5Bi0.5)TiO3–BaTiO3 system modified by Bi(Mg0.5Ti0.5)O3 and also low-melting additions KCl, NaCl–LiF, CuO, and MnO2 that favor the control of the stoichiometry and the properties of the ceramics have been studied. The ceramics are characterized by ferroelectric phase transitions that are observed as jumps at temperatures near 400 K and maxima at Tm ~ 600 K in the temperature dependences of the dielectric permittivity. The phase transitions at ~400 K demonstrate the relaxor behavior indicating the existence of polar domains in the nonpolar matrix. An increase in the content of Bi(Mg0.5Ti0.5)O3 favor a decrease in the electrical conductivity and dielectric losses of the samples, and the relative dielectric permittivity at room temperature ert is retained quite high, achieving the highest values ert = 1080–1350 in the ceramics modified with KCl.

Phase formation, crystal structure parameters, dielectric and ferroelectric properties of ceramic solid solutions in the (1-y)[(1-x)(Na0.5Bi0.5)TiO3-x(K0.5Bi0.5)TiO3]-yBiFeO3 system with x = 0.25, ...

The influence of BiFeO3 on phase formation, crystal structure, and dielectric properties of solid solutions close to the Morphotropic Phase Boundary in the (Na0.5Bi0.5)TiO3 - (K0.5Bi0.5)TiO3 system...

We have prepared ceramic (La0.8Sr0.2){[Ga0.8–x (Ge0.5Mg0.5) x ]Mg0.2}O3–d (LSGGM) (x = 0, 0.1, 0.2, 0.4, 0.6, 0.8) samples by solid-state reactions and studied their phase composition, structure, microstructure, and electrical conductivity. Phase-pure solid solutions have been obtained upon substitution of germanium and magnesium cations for up to 20 at % of the gallium cations. The modified samples have been shown to have high density, optimal microstructure, densely packed grains, and high electrical conductivity at high temperatures.

Influence of Bi(Mg0.5Ti0.5)O3 (BMT) on phase formation, unit cell parameters, microstructure, dielectric and ferroelectric properties of solid solutions close to the Morphotropic Phase Boundary in ...

Ceramic samples in the (La0.8Sr0.2){[Ga0.8–x (Si0.5Mg0.5) x ]Mg0.2}O3–d system (LSGSM) (x = 0, 0.1, 0.2, 0.4, 0.6, 0.8) were obtained by solid-phase synthesis, and their phase formation, structure, microstructure, and electric conductivity were studied. The substitution of gallium cations by silicon and magnesium cations was found to affect the phase formation, structure, microstructure, and electric conductivity of the ceramics. The replacement of up to 10 at % gallium cations by silicon and magnesium cations led to the formation of single-phase solid solutions in the LSGSM system. The silicon-containing samples are characterized by high density, optimum microstructure, close packing of grains, and high electric conductivity at high temperatures.

Influence of donor and acceptor dopants on structure, microstructure, dielectric, ferroelectric and local piezoelectric properties of (K 0.5 Na 0.5 )NbO 3 -based ceramics have been studied. Changes in dielectric parameters and effective d 33 piezoelectric coefficients were observed depending on solid solutions compositions.

We have studied the effect of preparation conditions on the structural, dielectric, piezoelectric, and other properties of ceramic samples cut from large, bulk hot-pressed bodies based on modified Bi3TiNbO9 and found conditions favorable for obtaining high piezoelectric parameters that ensure long-term functioning of Bi3TiNbO9-based ceramics at a temperature of 750°C.

We have studied the effect of Bi(Mg0.5Ti0.5)O3 additions on the phase formation, structural parameters, microstructure, and dielectric properties of solid solutions in the region of a morphotropic phase boundary in the BiFeO3–BaTiO3 system. Single-phase samples with the perovskite structure have been obtained and the addition of Bi(Mg0.5Ti0.5)O3 has been shown to raise the Curie temperature of the ceramics and improve their dielectric properties.

Single-phase ceramic samples in the morphotropic phase boundary region of the (1–y)[(1–x)(Na0.5Bi0.5)TiO3 ∙ x(K0.5Na0.5)NbO3] ∙ yBiFeO3 system (х = 0.06, 0.08, 0.10; y = 0.025, 0.05, 0.075, 0.10) have been prepared by solid-state reactions, and the effect of LiF as a low-melting-point additive (5 wt %) on the phase formation process and the dielectric properties of the solid solutions has been studied. The addition of LiF has been shown to activate the phase formation process and lower the sintering temperature of ceramic samples. The modification of the ceramics with lithium fluoride slightly increases the unit-cell parameters of the solid solutions. The addition of LiF lowers their Curie temperature.

Influence of BiFeO3 components on phase formation, unit cell parameters, microstructure, dielectric and ferroelectric properties of solid solutions close to the Morphotropic Phase Boundary in the (Na0.5Bi0.5)TiO3 - (K0.5Na0.5)NbO3 system has been studied. The formation of pure perovskite structure, decrease in the unit cell parameters, improvement of dielectric properties, and increase in the TC value stimulated by the BiFeO3 additives were revealed.

Influence of Bi(Mg 0.5 Ti 0.5 )O 3 (BMT) and KCl additives on phase formation, crystal structure, microstructure, dielectric and ferroelectric properties of ceramics with compositions close to the Morphotropic Phase Boundary in the (Na 0.5 Bi 0.5 )TiO 3 - BaTiO 3 (NBT-BT) system has been studied. The results obtained proved that modification of NBT-BT compositions by BMT and KCl additives promoted to improvement of dielectric properties.

The effect of the KCl additives with low melting temperature (∼1050 K), on the structural, dielectric and polar properties of 0.36BiScO3 - 0.64PbTiO3 ceramics was studied. The ceramics doped by the KCl additives were prepared by the solid state reaction method. Phase formation, polar and dielectric properties of modified ceramics were studied. Dense single phase samples doped by the KCl additives were obtained at lower temperatures in comparison with that of undoped samples. Influence of additives on dielectric properties was revealed.

We have prepared ceramic samples of solid solutions based on Bi-containing perovskite-like oxides near the morphotropic phase boundary in the K0.5Na0.5NbO3-BiScO3-AgSbO3 system and modified with LiF and MnO2 additions; investigated the phase relations, structure, and dielectric and ferroelectric properties of the ceramics; and determined their phase transition temperatures. The choice of superstoichiometric additives capable of intensifying the sintering process has been substantiated, and the effect of the additives on the Curie temperature of the ceramics has been examined.

A new approach to obtaining a functional glass ceramic based on potassium niobate from an amorphous precursor, obtained by rapid cooling of the melt containing small additions of the glass former SiO2, is examined. The results indicate that there is promise in the glass ceramic technology, which ensures the formation of cubic KNbO3 crystals of almost ideal habitus whose flat grains surrounded by thin, composition-regulated glass interlayers can stick to one another. The ceramic KNbO3 obtained by the glass ceramic technology differs beneficially from its conventional analog by low tana in the entire range of existence of the ferroelectric phase (below 410°C), which determines its advantage for a host of applications.

Ceramic solid solutions from the region of morphotropic boundary on the base of 0.36BiScO3-0.64PbTiO3, modified by complex additives of Bi2O3 and Ni2O3, Bi2O3 and MnO2, and LiF additives in amounts up to 5 w. % have been prepared by the conventional solid state reaction method. Decreasing of the phase formation temperature accompanies by increasing in density of the doped ceramics have been revealed. Influence of additives on microstructure, dielectric, ferroelectric properties, and effects of dielectric relaxation have been revealed.

Ceramic samples of 0.36BiScO3 · 0.64PbTiO3 morphotropic phase boundary solid solutions modified with low-melting additives (bismuth, nickel, and manganese oxides and lithium fluoride; < 5 wt %) have been prepared by solid-state reactions, and the phase formation, microstructure, and dielectric properties of the ceramics have been investigated. The additives were shown to lower the formation temperature of the solid solutions and raise the density of the ceramics. Varying the heat treatment conditions, we obtained single-phase samples, both large-grained, ranging in grain size from a few to tens of microns, and fine-grained, with a submicron-scale microstructure. The ceramics were shown to form through liquid-phase sintering. The additives influenced the dielectric properties, electrical conductivity, Curie temperature, and dielectric relaxation of the ceramics.

Dielectric and piezoelectric properties of ceramic solid solutions based on the compositions close to the MPB in the system (1-x)BiScO3 – xPbTiO3 (x- 0.63, 0.635, 0.64) have been studied. The 1st order phase transitions were observed at temperatures near 700 K. Increase in the lead titanate content stimulates slight increase in the TC value. Cr2O3 additives in amounts up to 0.2 w. % favor to the decrease of total conductivity and dielectric loss at high temperatures. Increase in the d33 and kt piezocoefficients was observed in modifed ceramic. Besides peaks in temperature dependences of dielectric permittivity and dielectric loss marked ferroelectric to paraelectric phase transitions, effects of dielectric relaxation, determined by oxygen vacancies were revealed.

Ferroelectrics with high TC > 600 K attract much attention due to prospects of their applications at high temperatures. In this work, influence of partial substitutions on the crystal structure and dielectric properties of lead-free bismuth oxides Ca(Bi1-x Nd x )4Ti4O15 (x = 0, 0.1) have been studied. Ceramic solid solutions have been prepared by the solid state reactions. Optimal temperatures of synthesis and sintering of the samples were determined. Phase composition, structure and microstructure of the samples were studied using the X-ray diffraction and scanning electron microscopy methods, respectively. Phase transitions and ferroelectric properties were studied by the dielectric spectroscopy. Positive effect of the Mn2O3 and Bi2O3 additives was proved. They favor to improving density of ceramics, inhibiting grain growth and to decreasing dielectric loss.

Layer-structured bismuth calcium titanate CaBi4Ti4O15 is regarded as one of the promising candidates among lead-free oxides for high temperature piezoelectric applications due to its high Curie temperature TC > 1000 K. Influence of partial cation substitutions on phase formation, microstructure and dielectric properties of CaBi4Ti3.6 B 0.4O15 (B – Ti, Cr, Ta) ceramics was studied. Ceramic solid solutions were synthesized by the conventional ceramic method and studied using the X-ray diffraction, scanning electron microscopy and dielectric spectroscopy over a wide temperature and frequency ranges. It was proved that Mn2O3 and Bi2O3 additives enhanced the phase formation process, improved density of ceramics and their dielectric properties.

Ceramic solid solutions on the base of composition from morphotropic phase boundary 0.36BiScO3-0.64PbTiO3 modified by the powdered Bi4Ti3O12 and Bi0.75Sr0.25O1.36 single crystals additives and by the low-melting LiF additive in amounts 5, 10, and 1 wt.%, respectively, have been prepared by the solid-state reactions method. The structure, microstructure, and dielectric properties of the ceramics have been studied. The influence of the additives on the morphology of ceramics, temperature of phase transitions, and effect of dielectric relaxation has been proved.

The ferroelectric and piezoelectric properties of ceramic solid solutions having a composition of (1−x)(Bi0.9Nd0.1)(Sc0.9 B 0.1)O3 − x PbTiO3 (x = 0.60–0.66; B = Lu, Yb, Er, Y) and obtained by solid state reaction were studied. An increase in the Curie temperature was found upon an increase in the concentration of lead titanate, while a drop occured upon the doping of the A and B sublattices. It was shown that at high temperatures, MnO2 and Bi2O3 additives lead to a reduction in the total conductivity and a dielectric loss of less than one order of magnitude. In modified ceramics, an increase in the d 33 and k t piezoelectric coefficients was observed as well. The effects of dielectric relaxation that are determined by the composition of the ceramics were revealed.

Ceramic solid solutions (Bi 1-y La y ) 4 (V 1-x Me x ) 2 O 11-y with x , y α -, orthorhombic β- and tetragonal γ- or γ’- polymorph modifications have been determined. Annealing of samples, containing large amount of Cu and/or La dopants, at 973 K in the reducing atmosphere resulted in their decomposition, though compositions containing low content of La, Ga or Zr dopants, remained pretty stable.

Ceramic solid solutions (1-x)(Bi0.9Nd0.1)(Sc0.9B0.1)O3 - xPbTiO3 (x = 0.60–0.66; B - Lu, Yb, Er, Y) based on the compositions close to the morphotropic boundary, have been prepared. To improve the phase content and the resistance of ceramics, Bi2O3 and MnO2 additives were used. Phase composition, structure, microstructure, phase transitions, ferroelectric and piezoelectric properties have been studied. The 1st order ferroelectric phase transitions are marked by peaks near 700–750 K in dielectric permittivity and dielectric loss temperature dependences. Effect of dielectric relaxation was observed, its relation to composition of ceramics determined. The Curie temperature TC increase was observed with increasing the PbTiO3 constituent, while the TC decrease is typical of the A- or B-cations doped compositions. Introduction of MnO2 and/or Bi2O3 additives lead to the decrease of total conductivity and dielectric losses to more than one order at elevated temperatures. Enhanced d33 and kt values were measured i...

Molecular dynamic simulation has been used to study how the sputtering characteristics of metal polycrystals are dependent on the mass m 1 of bombarding ions of low-energy E 0 . The influence of target parameters on mass dependence of sputtering has been calculated for Al, Ba, Ce and Au, which were not previously studied. These metals have very different values of density ρ , the lattice constant d , and the surface binding energy E b (the parameters that define the sputtering process). The features of sputtering characteristics for the metals studied are discussed.

Ceramic solid solutions Bi 4 (V 1−x Zr x ) 2 O 11−z (I), (Bi 1−y La y ) 4 V 2 O 11−z (II) and (Bi 1−y La y ) 4 (V 0.96 Zr 0.05 ) 2 O 11−z (III) with x < 0.30, y < 0.20, were prepared by the solid state reaction method and were investigated by means of various experimental techniques. The low temperature ferroelectric α-phase exists in the solid solutions with x, y ≤ 0.05. The phase transition to paraelectric β-phase was revealed in these compositions by the dielectric spectroscopy, SHG and DTA/DSC methods. Dielectric permittivity measurements confirmed an effect of the domain walls “pinning” due to the presence of oxygen vacancies inherent to the bismuth vanadate based structures. Switching of ferroelectric domains by an external electric field was observed in Piezoresponse Force Microscopy experiments.

Ceramic solid solutions (Bi1 − xLax)4V2O11 − z(I), Bi4(V1 − xFex)2O11 − y (II), and (Bi1 − xLax)4(V0.96Fe0.04)2O11 − y (III) (x = 0–0.3, step Δx = 0.02) are prepared using solid-phase synthesis. The concentration and temperature ranges of stabilization of different polymorphic modifications, including the ranges of concentrations x corresponding to the stabilization of the ferroelectric phase, are established. It is revealed that an increase in the concentration x in the region of existence of the pseudoorthorhombic phase α of the solid solutions studied leads to a decrease in the transition temperature, smearing of the transition, and an increase in the width of the thermal hysteresis of the ferroelectric phase transition. The effect of compressing of the domain walls by oxygen vacancies was revealed in the samples from the region of existence of the ferroelectric α phase, and the effect of dielectric relaxation was detected in the samples from the region of existence of the orthorhombic phase β.

ZrO2-CeO2 (10, 18, and 23 mol % CeO2) solid solutions have been synthesized via coprecipitation. The powders have been sintered at 1875 K, and the electrical conductivity and dielectric properties of the resultant ceramics have been studied. The dielectric relaxation observed in the ceramics can be understood in terms of ionic transport accompanied by the formation of dipoles relaxing in an ac electric field.