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In this communication, the synthesis (solid-state reaction route) and characterization (structural and electrical properties) of Li/Fe modified barium tungstate BaWO 4 of chemical formula (BaLi)(FeW)O 6 double perovskite have been reported. Analysis of room temperature X-ray diffraction data shows the formation of a new single-phase (double perovskite) of tetragonal symmetry. The calculated average crystallite size and lattice strains are found to be 42 nm and 0.111% respectively. The scanning electron micrograph shows that grains are distributed uniformly with less porosity in the material. Detailed studies of field (frequency) and thermal (temperature) dependence of capacitive (dielectric) and resistive (impedance and conductivity) characteristics of the prepared material have shown the dielectric dispersion, relaxation, and non-Debye type of conduction mechanism respectively of the material. The existence of a non-Debye type of relaxation process and thermally activated relaxation process in the material has been analyzed by using impedance spectroscopy and conductivity techniques respectively. The presence of the depressed semicircular arcs in both Nyquist and Cole-Cole plots confirms the semiconductor nature of the material, which is well supported from ZSIMPWIN fitted impedance data. Study of room temperature Raman spectra supports the incorporation of Li/Fe of LiFeO 2 in BaWO 4 to produce new double perovskite of a composition BaLiFeWO 6 of tetragonal symmetry. Further, as the temperature dependence of resistance shows a good stability factor, sensitivity factor, and thermistor constant, the material may be useful for thermistor-related devices. The nature of I–V characteristics confirms the presence of the Ohmic type of conductivity of the material. The energy bandgap of 2.85 eV, obtained from the UV–visible spectrum, suggests the material may also be used for optoelectronic devices. [ABSTRACT FROM AUTHOR]

In this communication, preliminary structural and detailed electrical (dielectric, polarization, impedence, and conductivity) characteristics of BaSnO 3 and BaSeO 3 modified complex Bi 0.5 Na 0.5 TiO 3 ceramics with a general chemical formula and composition, (1–2x)[(Bi 0.5 Na 0.5) TiO 3 ]+x(BaSnO 3)+x(BaSeO 3) (with x = 0, 0.05, 0.1, 0.15) (BNT–BSn–BSe) ceramics, synthesized by a high-temperature mixed-oxide technique (calcinations temperature = 925 °C and sintering temperature = 950 °C, for time = 4 h each) have been reported. Analysis of room temperature X-ray diffraction data has confirmed the formation of single phase perovskite of BNT–BSn–BSe in rhombohedral phase and provided crystal data. Studies of impedance spectroscopy and electrical conductivity of the materials in a frequency range of (1 kHz-1MHz) at different temperatures (25–500 °C) have shown the composition (x) effect on electrical characteristics of BSn and BSe modified BNT.The electric field dependent polarization study at room temperature exhibits the existence of ferroelectricity in the materials. Study of the impedance spectroscopy through Nyquist plots shows the contributions of the grains and grain boundary in the resistive and capacitive properties of the materials. This study also determines the existence of NTCR (negative temperature coefficient of resistance) behavior the prepared materials. The J–E characteristics demonstrate the Ohomic behavior with slope closer to 1. [ABSTRACT FROM AUTHOR]

The (Bi 0.85 Tm 0.15)FeO 3 (BTFO) and BiFeO 3 (BFO) ceramic compounds have been prepared by using a standard ceramic technology (i.e., high-temperature solid-state reaction route). The formation of the above compounds was checked by the detailed analysis of X-ray diffraction (XRD) data using standard computer programming software 'POWD'. All the diffraction peaks of the XRD patterns of the above compounds were indexed through JCPDS files of X'Pert High Score plus. These compounds (BFO and BTFO) were found to crystallize in rhombohedral symmetry with few impurity phases present in the structure. A dielectric peak observed in a temperature range of 250C–350 °C is due to the magnetic phase transition occurring in the materials (BFO and BTFO). The calculated value of tolerance factor reveals the degree of distortion occurring in the ideal perovskite structure. Impedance study indicates the presence of both NTCR (negative temperature coefficient of resistivity) and PTCR (positive temperature coefficient of resistivity) behavior in a different temperature range. The role of grain and grain boundary effects in the electrical properties was discussed with the respective fitting parameters (R g , R gb , CPE etc.) of the materials. Activation energy has been calculated at different temperature through Nyquist plot, and also from the slopes of Arrhenius (σ ac ∼1/T) plot. The polarization versus electric field (PE) hysteresis loops of BFO and BTFO gave the evidence of ferroelectric behavior present in the compounds. [ABSTRACT FROM AUTHOR]

The synthesis and characterization (structure, dielectric, electrical, and optical properties) of Ba 1-x Zn x (Fe 1/2 V 1/2)O 3 (x = 0,0.05,0.10,0.15) have been reported in this paper. The development of a single-phase orthorhombic structure has been confirmed by analyzing room temperature X-rays diffraction (XRD) patterns/data. The crystallite size decreases with an increase in the concentration of Zn2+. Different vibration modes are confirmed from Raman Spectroscopy. Analysis of FESEM microstructure confirms the reduction in average grain size with increased Zn2+ concentration. Some electrical parameters (dielectric constant, conductivity, and impedance) have provided valuable data on the conduction mechanism, structure-properties relationship, etc. The non-Debye relaxation is confirmed from the Nyquist plot. It also ensures the grain boundary and the bulk effect of the materials. The coercive field and efficiency are maximum (7.419 kV/cm, 60.83%) for the higher concentration of Zn2+(x = 0.15). The direct band gap varies from 3.28 to 3.10 eV with increasing Zn2+ concentration. It confirms the generation of more free electrons in the conduction band and high conductivity. • Samples are prepared by the solid state reaction method. • The crystallite size decreases with an increase in the concentration of Zn2+. • Reduction in average grain size with an increase in the concentration of Zn2+. • The coercive field and efficiency increase with a higher concentration of Zn2+. • The direct band gap decreases with increasing Zn2+ concentration. [ABSTRACT FROM AUTHOR]

La 0.5 Na 0.5 Ga 0.5 V 0.5 O 3 (LNGVO) ceramic was prepared using a high-temperature solid-state reaction method. The structural phase, microstructure, dielectric, ferroelectric and optical properties of the material were systematically investigated. The preliminary structural analysis using x-ray diffraction (XRD) data shows the formation of the material in an orthorhombic crystal structure at room temperature. Detailed studies of dielectric and electrical properties have been carried out over a wide range of frequency (1 kHz–1 MHz) and temperature (25–450 °C) in order to elucidate the basic mechanism of the conduction and relaxation process. The dielectric characteristics show that the ceramic is a relaxor with strong diffuse phase transition and frequency dispersion. The nature of the variation of ac conductivity as a function of frequency obeys the universal power law, and confirms the existence of a hopping conduction mechanism in the material. The material also exhibits ferroelectricity at room temperature with a very low value of remnant polarization. The ionic conductivity and transport number of the ferroelectric ionic conductor were obtained with the standard experiment and calculation respectively. The material shows NTCR behavior similar to that of a semi-conductor. Similar behavior has also been observed in the study of I–V characteristics of the material. [ABSTRACT FROM AUTHOR]

• Synthesis of BaNaFeWO 6 double perovskite from two non-perovskites (BaWO 4 and NaFeO 2). • Semiconducting property is confirmed from study of the ac conductivity. • The study of P-E confirms ferroelectric behavior. • The study of UV spectroscopy provides bandgap of 2.64 eV, good range for optoelectronic devices. • NTC thermistor applications. In this paper, the synthesis (by solid-state reaction route) and characterization (structural, microstructural, electrical, and optical properties) of the BaNaFeWO 6 lead-free double perovskite are reported. Room temperature structural analysis suggests that the material crystallizes in monoclinic crystal symmetry with average crystallite size and lattice strain of 55 nm and 0.023% respectively. The incorporation of the Na/Fe at both sites (Ba and W) of BaWO 4 is confirmed from the room temperature Raman study. A study of microstructural and compositional characteristics of the sample by using scanning electron microscopy (SEM) and EDAX (energy dispersive analysis X-ray) has provided the quality (uniform and compactness) of the sample. The detailed studies of the frequency and temperature dependence of dielectric, impedance, and conductivity properties of the material suggest the presence of high dielectric dispersion, non-Debye conduction, and relaxation mechanism in it. The semiconducting nature is confirmed by the decreasing resistance or radius of semicircular arcs in both impedance analysis and Nyquist plots. This nature is also well supported by fitted parameters evaluated using ZSIMPWIN software. The temperature dependence of resistance provides a good stability factor, sensitivity factor, and thermistor constant, which may be useful for applications in the fields of the thermistor-related devices. The field-dependent polarization (P-E) hysteresis loop suggests the possibility of ferroelectricity in the sample. The sample has an energy bandgap of 2.72 eV deduced from its UV–visible spectrum, which may be useful for some applications in optoelectronic devices [ABSTRACT FROM AUTHOR]

Comprehensive study of structural, dielectric, electrical, and ferroelectric characteristics of Yttrium Barium Copper Oxide (Y 2 BaCuO 5) ceramic, (accompanying phase of high-Tc superconductor YBa 2 Cu 3 O 7-X can unravel plethora of fascinating applications. Y 2 BaCuO 5 green phase cuprate has been prepared by employing ceramic fabrication technology. Room-temperature X-ray diffraction data of the polycrystalline sample suggests that it crystallizes in orthorhombic system in non-centrosymmetric Pbn2 1 spacegroup. The microstructure and elemental composition clearly illustrated by SEM micrograph and EDAX data. Frequency dependence of dielectric parameter has been discussed using Maxwell-Wagner model. Grain and grain boundary effects discussed using Nyquist plots; fitted to RQC and RC-RQC circuits. Temperature and Frequency dependent conductivity behaviour are explained using Arhenius equation and Jonscher power law. NSPT and CBH model of charge transport mechanisms observed. (I–V) charecteristics demonstrates semiconductor behaviour of Y 2 BaCuO 5 and its suitability for rectifier applications. Existence of hysteresis loop at room and high temperature up to 200 °C suggests ferroelectricity in Y 2 BaCuO 5. • Y 2 BaCuO 5 , a promising rare-earth cuprate, synthesized using cost-effective ceramic fabrication technique. • The green phase cuprate crystallizes in the non-centrosymmetric space group Pbn2 1 of orthorhombic crystal system. • Structural and microstructural analysis carried out using X-ray, SEM and EDAX. • Maxwell-Wagner polarisation effect along with various conduction mechanisms like CBH and NSPT observed in this compound. • Impedance spectroscopy (nyquist plot) of the sample suggests contribution of both Bulk and interface effects. • I-V charecteristics and leakage current behaviour suggest semiconducting behaviour of the sample. [ABSTRACT FROM AUTHOR]

Abstract: Tailoring of physical properties of multiferroic BiFeO3 was carried out by introducing NaTaO3 ferroelectric to form (Bi1−x , Na x ) (Fe1−x , Ta x ) O3 (x=0.0, 0.1, 0.2 and 0.3) solid solutions. The formation of the desired materials was confirmed by the X-ray diffractions analysis. The surface texture of the prepared materials, recorded by scanning electron microscope (SEM), exhibits a uniform grain distribution with few small voids suggesting the formation of high-density pellet samples. The impedance and dielectric properties of the materials were investigated for different concentrations (x) of NaTaO3 as a function of temperature and frequency. The relative dielectric constant and loss tangent decrease with increase in NaTaO3 concentration in the system. The grain and grain boundary contributions in the resistive and capacitive components of the samples were estimated using the complex impedance spectroscopy technique. The value of activation energy due to both grain and grain boundary is nearly same, but increases with an increase in composition (x). The nature of variation of dc conductivity confirms the Arrhenius-behavior of the materials. Study of frequency dependence of ac conductivity suggests that the material obeys Jonscher׳s universal power law, and the presence of ionic conductivity is observed. [Copyright &y& Elsevier]

Abstract: A lead free polycrystalline material Sr(Bi0.5Nb0.5)O3 was prepared using a high-temperature solid-state reaction technique. Preliminary X-rays diffraction studies exhibit the formation of a single-phase compound in the orthorhombic crystal system. The study of microstructure of gold-coated pellet by scanning electron microscopy (SEM) shows well-defined and homogeneous distribution of grains on the surface of the sample. Detailed studies of dielectric parameters (i.e., ε r and tan δ) of the compound as a function of temperature at selected frequencies reveal that the values of these parameters are almost independent of temperature. Studies of impedance and related parameters exhibit that these electrical properties of the material are strongly dependent on temperature, and bear a good correlation with the microstructure of the material. The decrease in value of bulk resistance on increasing temperature suggests the existence of negative temperature co-efficient of resistance (NTCR) in the material. Studies of electric modulus show the presence of hopping conduction mechanism in the material with non-exponential-type of relaxation. The nature of variation of dc conductivity with temperature confirms the Arrhenius- and NTCR- types of behaviors of the material. The ac conductivity spectrum provides a typical-signature of an ionic conducting system, and is found to obey Jonscher′s universal power law. [Copyright &y& Elsevier]

The polycrystalline sample of (Bi0.5Li0.5)(Fe0.5Nb0.5)O3was prepared by a solid-state reaction method. Preliminary X-ray structural analysis of the sample suggests the formation of a tetragonal phase with a new unit cell configuration. Dielectric, electrical, impedance and modulus properties of the material were investigated in a wide range of temperature (25–500 °C) and frequency (1 kHz–1 MHz). Two dielectric anomalies observed at 295 °C and 400 °C clearly suggest the existence of magnetic phase transition and two relaxation processes in the system. Dielectric properties have greatly been improved on addition of LiNbO3to BiFeO3. The appearance of a hysteresis loop at room temperature confirms the ferroelectric properties of the material. The nature of the Nyquist plot confirms the presence of both bulk and grain boundary effects in the material. The ac conductivity was found to obey Jonscher's power law. The dc conductivity variation with temperature follows the Arrhenius equation. The induced voltage changes with the applied magnetic field, showing that the sample is multiferroic. [ABSTRACT FROM AUTHOR]

Abstract: The current research work reports on structural, dielectric, pyroelectric and conduction properties of strontium orthotantalate, prepared by using a high-temperature solid-state reaction technique. Preliminary x-rays structural study of the material confirms the formation of a single-phase compound with trigonal crystal structure. The microstructure of gold-coated pellet sample recorded by scanning electron microscopy (SEM) shows well-defined and homogeneously distributed grains. Detailed studies of dielectric parameters (ε r and tan δ) of the compound as a function of temperature at some selected frequencies reveal that these parameters are invariant in a wide range of frequency and temperature (room temperature to about 400°C). Studies of pyroelectric properties reveal that the materials have reasonably high figure of merit useful for fabrication of pyroelectric detector. The ac conductivity spectra show a typical-signature of an ionic conducting system, and are found to obey Jonscher's universal power law. The low leakage current and negative temperature coefficient of resistance (NTCR) behavior of the sample have been verified from J~E plots. The nature of variation of dc conductivity with temperature confirms the Arrhenius and NTCR behavior in the material. [Copyright &y& Elsevier]

Abstract: Preliminary structural and detailed dielectric and electrical properties of zirconium (Zr) modified-sodium bismuth titanate (i.e., Na0.5Bi0.5Ti1−x Zr x O3(NBZT)) ceramics were studied. Structural analysis of the materials with room temperature X-ray diffraction data confirmed the formation of compounds in the rhombohedral crystal system. SEM micrographs of the compounds showed the abnormal grain growth but with better densification and homogeneity on substitution of Zr at the Ti site. Dielectric and complex impedance spectroscopic studies were carried out in a wide frequency (i.e., 102–106 Hz) and temperature (30–500°C) range. The maximum permittivity (at transition temperature) was found to be decreased on increasing Zr concentration in NBZT but the diffuseness of dielectric peak increases. The nature of frequency dependence of ac conductivity of NBZT follows the Jonscher power law, and calculated dc conductivity follows Arrhenius behavior. Detailed studies of complex impedance spectroscopy have provided better understanding of: (i) relaxation process and (ii) microstructure-properties relationship in the materials. Complex impedance and modulus spectra confirm the significant contribution of both grain and grain boundary to electrical response of the materials. It is observed that relaxation processes in the materials are of non-Debye type. [Copyright &y& Elsevier]

Abstract: The effect of plasticizer (polyethylene glycol, PEG200) on dielectric and electrical properties of an ionically conducting polymer nanocomposites PEO25-NaI+5wt.% DMMT (dodecyl amine modified Na+-montmorillonite)+ x wt.% PEG200 with different value of x has been investigated. At low frequency, the variation of relative dielectric constant with frequency shows the presence of material electrode interface polarization processes. The tangent loss peaks appearing at a characteristic frequency suggest the presence of relaxing dipoles in all the samples. On addition of plasticizer, the peak shifts towards higher frequency side suggesting the speed up the relaxation time. The electrical modulus formalism is used to study the ionic relaxation processes in these composites in terms of conductivity relaxation time. Analysis of electrical modulus and dielectric permittivity functions suggest that ionic and polymer segmental motions are strongly coupled. The frequency dependence of ac conductivity follows the universal power law with a small deviation in the low frequency region due to the electrode polarization effect. [Copyright &y& Elsevier]

Abstract: The polycrystalline sample of Na1/2Dy1/2TiO3 ceramic was prepared by a standard high-temperature solid-state reaction technique. X-ray structural analysis confirmed the formation of single-phase (with minor secondary phase) compound in the orthorhombic (distorted tetragonal) crystal system at room temperature. Study of surface morphology by scanning electron microscope exhibits uniform distribution of rectangular/cubical grains with less voids. The elemental composition of the prepared compound was confirmed by energy dispersive X-ray spectroscopy microanalysis. Detailed studies of dielectric properties exhibit a dielectric anomaly at 94°C suggesting a possible ferroelectric–paraelectric phase transition in the compound. The activation energy (E a), calculated from the temperature dependence of ac conductivity plot, was found to be small (∼0.1eV) in low temperature and large (∼0.5eV) in high temperature region. [Copyright &y& Elsevier]

Abstract: The polycrystalline samples of Pb(Zr0.65−x Mn x Ti0.35)O3 (x =0, 0.05, 0.10, 0.15) (PZMT) were prepared by a high-temperature solid-state reaction technique. Structural properties of the compounds were examined using an X-ray diffraction (XRD) technique to confirm the formation of single-phase compounds (with perovskite structure) at room temperature. Microstructural analysis of the surface of the compounds by scanning electron microscopy (SEM) exhibits that there is a significant change in grain size on introduction, at the Zr-site, of Mn. Detailed studies of the dielectric properties of PZMT show a measurable shift in T c, change in dielectric constant, and ac conductivity. [Copyright &y& Elsevier]

Abstract: Polycrystalline samples of Nd2(Ba0.5R0.5)2O7 (R=W, Mo) were synthesized using a high-temperature solid-state reaction technique. A preliminary structural (XRD) analysis of these compounds show the formation of a single-phase orthorhombic system at room temperature. The scanning electron microscopic (SEM) study with different magnifications provides information on quality of these samples and the uniform grain distribution over the entire surface of the samples. Detailed studies of dielectric constant (ε r and loss tangent (tan δ)) as a function of frequency (50–104 Hz) at different temperatures (300–623K) revealed that the compounds do not have any dielectric anomaly in the studied frequency and temperature range. The nature of variation of (dc) resistivity at three different temperatures, and its variation with temperature (∼300–623K) at a constant electric field (50V/cm) showed the semiconductor characteristics of the materials. [Copyright &y& Elsevier]

Abstract: The polycrystalline sample of Y 3Fe5O12 was prepared by a high-temperature solid-state reaction technique. A preliminary X-ray structural analysis exhibited the formation of single-phase compound with a tetragonal structure. SEM micrograph of the material shows the uniform distribution of grains throughout the surface of the sample. Detailed studies of dielectric and electrical properties of Y 3Fe5O12, investigated in a wide frequency range (100 Hz–1 MHz) at different temperatures (26–500 ∘C) by complex impedance spectroscopy technique, showed that these properties of the material are strongly dependent on frequency and temperature. A dielectric anomaly was observed at 282 ∘C, which may be related to the magneto-electric response of this material. [Copyright &y& Elsevier]

Abstract: The polycrystalline samples of La-modified Bi(Sc1/2Fe1/2)O3 (i.e., (Bi1−x La x )(Sc1/2Fe1/2)O3) were prepared using a solid-state reaction technique. The formation of single-phase compound was checked with an X-ray diffraction (XRD) technique. A small amount of La-substitution (0≤ x ≤0.15) at the Bi site does not change the crystal structure of Bi(Sc1/2Fe1/2)O3. Detailed studies of dielectric properties (i.e., dielectric constant, loss tangent and ac conductivity) showed significant effect of La doping on these properties. High dielectric constant with relatively low loss tangent and electrical conductivity of the mixed-type (i.e., space charge and oxygen ion vacancies) are some of the special features of the La-modified Bi(Sc1/2Fe1/2)O3 compounds. [Copyright &y& Elsevier]

Abstract: Polycrystalline La3/2Bi3/2Fe5O12 (LBIO) compound was prepared by a conventional high-temperature solid-state reaction technique. Preliminary X-ray diffraction (XRD) analysis confirms the formation of single-phase compound in an orthorhombic crystal system at room temperature. The elemental content of the compound has been analysed by EDS microanalysis. Microstructural analysis by scanning electron microscopy (SEM) shows that the compound has well defined grains, which are distributed uniformly throughout the surface. Studies of temperature variation of dielectric response at various frequencies show multiple dielectric anomalies at 200 and 370 ∘C. It is interesting to note that the loss tangent seems to be reduced at higher frequencies after reaching the instrumental saturation. Also, a couple of weak endothermic peaks were observed in differential thermal analysis (DTA) corresponding to 200 and 370 ∘C phase transition temperature. As soon as the phase transition process sets in, the DTA curve deviate from the basal horizontal line. The ferroelectric hysteresis loop was observed by applying the electric field of 6 kV/cm. [Copyright &y& Elsevier]

Abstract: Nanosized piezoelectric ceramics for vibration sensor applications have been prepared by mixing the ferroelectric PLZT (8:60:40) with variable doping fractions of trivalent aluminium ion (Al3+). Samples have been prepared through a standard sol–gel route. X-ray diffraction and scanning electron microscopy (SEM) have been used to determine the phase and morphological modifications. Transmission electron microscopy (TEM) studies reveal the microstructure with nanosized well-dispersed homogeneous spherical particles. The vibrational infra-red (IR) spectroscopy record is taken to locate the position of the doping Al3+ ion. Using electrical impedance spectroscopy, the resonance and anti-resonance frequencies of the Al modified PLZT system have been determined and analysed. Al addition in PLZT has left a profound effect in its dielectric and piezoelectric properties. An interpretation of the role of Al addition is proposed in terms of structure modification. The sensing power of the investigated material was found useful for the vibration control of a cantilever beam. [Copyright &y& Elsevier]

Abstract: Ferroelectric [Pb0.92(La1−z Sb z )0.08][Zr0.60Ti0.40]O3 for z =0.0, 0.3, 0.6, 0.9 and 1 were prepared from their constituent oxides by a solid state reaction technique. The powders were calcined in the temperature range of 1000°C for 6h. Phase formation, crystal structure and lattice parameter were investigated by X-ray diffraction (XRD) technique. The compacts were sintered at 1250°C for 2h and their dielectric, ferroelectric and conductive properties were measured. The ferroelectric behavior of the doped samples was studied from their hysteresis loop. [Copyright &y& Elsevier]

The polycrystalline samples of Ba5LaTi3−xZrxNb7O30 (x=0, 1, 2 and 3) complex tungsten–bronze (TB) compounds were prepared using a high-temperature solid-state reaction technique. Room temperature preliminary X-ray diffraction (XRD) studies of the compounds showed the formation of single-phase compounds with an orthorhombic crystal structure. Detailed studies of dielectric properties (ϵ, tanδ, σac) of the above compounds as a function of frequency (200 Hz–1 MHz) at room temperature and as a function of temperature (−190 to 400 °C) at four different frequencies (1, 10, 100 and 1000 kHz) show that these compounds have a diffuse-type of phase transition with relaxing property. Transition temperature of the compounds was found to be below room temperature that increases with rise in frequency. The broadening of dielectric peaks and shift of Tc upward with increasing frequency shows the relaxing behavior of these compounds. [Copyright &y& Elsevier]

Polycrystalline samples of Pb(Mg1/4 Ni1/4 W1/2)O3 (PMNW) have been prepared by a conventional solid-state reaction. Preliminary room temperature X-ray study shows the formation of single-phase compound with cell parameters a = 9.8045 (28) Å, b = 13.1280 (28) Å and c = 14.42072 (28) Å. Dielectric anomaly and ferroelectric phase transition observed at 76°C was supported by our polarization study. The variation of dc resistivity of the material with temperature shows its semiconducting behaviour. [ABSTRACT FROM AUTHOR]

A polycrystalline sample of thallium telurate, Tl2TeO4, was prepared by a solid-state reaction technique. Preliminary X-ray structural study of the compound reveals the formation of single phase orthorhombic compound at room temperature. Detailed studies of dielectric constant as function of temperature and frequency suggest that the compound undergoes two phase transitions at 3°C and 272°C. Variation of dc resistivity with temperature shows that the conductivity of the material increases with the rise in temperature. [ABSTRACT FROM AUTHOR]

In this communication, the structural and electrical (dielectric, polarization, impedence, and conductivity) properties of the polycrystalline samples of Ca/Zr modified BiFeO 3 samples with chemical formula (Bi 1-x Ca x) (Fe 1-x Zr x)O 3 ; x = 0.05, 0.1, 0.15, 0.20 were prepared using a solid-state reaction method at 800 °C have been reported. The analysis of room temperature X-ray diffraction data of above-synthesized electro-ceramics confirms the formation of single phase perovskite in rhombohedral phase. The scanning electron microscope photographs provide the micro-structural study of the samples. The existence of ferroelectricity in the materials was studied by the variation of electric polarization with the applied electric field. Many important results have been obtained from the dielectric and impedance studies of the samples at a varying frequency (1 kHz–1000 kHz) and temperature (250C–300 °C). The contribution of both grains and grain boundaries towards the total resistance and capacitance of the four compounds is found from the Nyquist plots. From the conductivity study, the dielectric properties and conductivity of the materials were obtained. The J–E characteristics of the samples provide the Ohmic behavior with slope closer to 1. • Rietveld refinement confirms the compounds crystallize with rhombohedral (R 3 c) symmetry. • A small tangent loss with high dielectric constant and improved ferroelectric characteristics are achieved. • The P-E loops show the ferroelectric behavior. • The J-E characteristics confirms the Ohmic behavior. [ABSTRACT FROM AUTHOR]

Abstract: The Vogel–Fulcher (V–F) relation has long been adopted to extract the freezing temperature from a dielectric constant–temperature plot. It has been shown that the V–F relation in the relaxation time scale can be used for a more direct evaluation of rather than . But in our opinion, neither nor gives direct evidence of freezing. Hence, in this letter, we have tried to give direct evidence for relaxor freezing and direct evaluation of for a relaxor system [ Pb(Mg1/3Nb2/3)O3 with 20 mol% BiFeO3] using differential scanning calorimetric and pyroelectric measurements. [ABSTRACT FROM AUTHOR]

The compounds (Bi 1/2 Ba 1/4 Sr 1/4)(Ti 1/2 Fe 1/2)O 3 (BFBST-0), (Bi 1/2 Ba 1/4 Sr 1/4)(Ti 1/4 R 1/4 Fe 1/2)O 3 (BFBST-1 for R = Zr and BFBST-2 for R = Sn) have successively been prepared through the high-temperature solid-state reaction route. The structural (XRD) analysis through the Rietveld refinement reveals the tetragonal (P 4mm) phase of the compounds. The refined site occupancy and respective fractional coordinates support the stoichiometry of the compounds. The dielectric, electrical (impedance and conductivity) and ferroelectric properties are investigated. The materials are having a diffused type of dielectric behavior and a variety T C indicating the relaxation effect. The deviation from the very conventional Curie Weiss law is explained through the diffusion coefficient (1≪ γ 2). Zr and Sn substitution increased the resistivity, decreased the dielectric loss and the leakage current of the parent (BFBST-0) sample. The leakage behavior is analyzed through J ~ E plots. The findings include the decreased value of the leakage current as well as dielectric loss with the addition of Zr and Sn in B-site as compared to that of the parent BFBST-0. This may signify the pathway to enhance the applicability of the BFBST system. The grain and grain boundary effects are explained through the Nyquist plots. A negative temperature coefficient of resistance (NTCR)/semiconductor like behavior can be seen in the studied samples. The activation energy (E a) is calculated from the Arrhenius fit of inverse temperature versus AC conductivity curves. The E a is higher at the high temperature region as compared to that of the low temperature region. Image 1 • It is possible to produce a single phase (perovskite) BFBST by low cost solid state reaction route. • Fractional coordinates and the site occupancies are investigated with very less thermal parameter value. • Zirconium and Tin substitution increases resistivity, lowers dielectric loss and conductivity of BFBST. • A well defined relaxation mechanism was discussed and compared between the samples through the impedance analysis. • Zirconium and Tin substitution decreases the leakage current as compare to the parent BFBST. [ABSTRACT FROM AUTHOR]

BiHoZnCeO6, the double pervoskite was synthesized using a cost-effective solid-state reaction method. The structural evaluation of the double pervoskite, when carried out by using the X-ray diffraction pattern suggested an orthorhombic crystal geometry with non- centrosymmetry space group Pca21. The microstructural investigation on the above material is carried out with the help of a scanning electron micrograph. These SEM micrographs showed that the grains of varying sizes (0.5–2 μm) are uniformly distributed. The study of dielectric characteristics as a function of temperature and frequency revealed some interesting characteristics of the material. One such observation is the identification of ferroelectric transition temperature at 435 °C. The strong anomaly at 435 °C and the ferroelectric behavior of the material is further validated by the study of spontaneous polarization (the hysteresis loop). In the present communication, the detailed microstructural, dielectric (dielectric constant, tangent loss, and electric polarization), thermal and electrical (impedance, electrical modulus, conductivity) studies on bismuth holmium zinc ceranate is presented along with the existence of ferroelectricity. [ABSTRACT FROM AUTHOR]

Examines the structural, electrical and dielectric properties of Na2W4O13 ceramic. Preparation of the polycrystalline sample of Na2W4O13 by a high-temperature solid-state reaction technique using high purity ingredients; Use of racalcined homogenous powder to make cylindrical pellets and polyvinyl alcohol as a binder to reduce the brittleness of the pellets.

Nowadays, there have been much consideration to develop eco-friendly advanced materials, which have many applications in the field of multiferroics, sensors, actuators, magnetically modulated transducer devices, etc. Hence, the preparation of lead-free based multifunctional materials has now become of great interest to researchers. The present study reports the synthesis and study of structural, dielectric, and multiferroics characteristics of (Bi 0.8 Nd 0.2)(Fe 0.5 Ti 0.5)O 3 material. The compound was synthesized using a conventional solid-state reaction method (calcination at 950 °C). The X-ray diffraction analysis of the compound confirms the single-phase formation with orthorhombic symmetry. The surface morphology of the material has been examined by the field emission scanning electron microscopy (FESEM) method, which shows uniform grain distribution in the microstructural image. Grains were to be found of different sizes with few voids. Energy dispersive X-ray (EDX) shows the purity of the sample with an equivalent amount of weight and atomic percentage. Dielectric and impedance analysis have been investigated in a wide range of frequencies and temperatures. Frequency-dependent ac-conductivity obeys Jonscher's universal power law. The P-E loop tracer was used to study the ferroelectric nature of the sample. Magnetic field-dependent magnetization is measured at room temperature by a vibrating sample magnetometer (VSM). The current study provides efficient, eco-friendly, and interesting results for further application purposes. [ABSTRACT FROM AUTHOR]

The synthesis and characterization (structure, dielectric, electrical properties) of ceramic technology prepared gadolinium modified bismuth titanate of a composition Bi 4-x Gd x Ti 3 O 12 (x = 0, 0.1) have been reported in this paper. The development of a single-phase orthorhombic structure with a space group Aba2 has been confirmed by analysing room temperature X-rays diffraction (XRD) patterns. The plate-like microstructures of the samples are revealed by scanning electron microscope, which confirmed the layered perovskite structure of Bi 4-x Gd x Ti 3 O 12 (x = 0,0.1). The crystallite size (D) and strain (ε), calculated from the W–H (Williamson-Hall) plots, are found to be 64 nm, 0.001, respectively for BIT (bismuth titanate, Bi 4 Ti 3 O 12) and 53 nm, 0.009, respectively for Gd modified BIT. Some obtained electrical parameters (dielectric constant, conductivity, electrical impedance, and modulus) of BIT and Gd modified BIT have provided useful data on the conduction mechanism, structure-properties relationship, etc. The Nyquist plots confirm the contribution of grain boundary and the bulk effect to the properties (physical) of the materials. [Display omitted] • Samples are prepared by the solid state reaction method. • The crystallite size decreases for Gd doped BIT. • The average grain size decreases for Gd doped BIT. • The efficiency increases for Gd doped BIT. [ABSTRACT FROM AUTHOR]

Dependence of tan δ on temperature. [Display omitted] • Rietveld refinement technique confirms the compound crystallizes with monoclinic symmetry. • The SEM micrograph shows two different types of the material present; a low dense polyhedral grain material and a foamy material, consisting of very small particles. • The isotropy value shows the grain texture and compactness on the surface. • A small tangent loss with high dielectric constant and improved ferroelectric properties. • The decreasing behavior of activation energy suggests the hopping of electrons in the material. • Temperature dependence of resistance yields a negative temperature coefficient of resistance (NTCR) behavior of the compound. In this communication, preliminary investigation of structural and detailed analysis of electrical proprties of a new barium bismuth tungstate of a chemical composition Ba 3 Bi 2 WO 9 , produced via a standard high-temperature solid-state reaction method, is presented. The basic crystal structure of the compound is monoclinic (a = 8.4621 Å, b = 6.7358 Å, c = 6.9064 Å and β = 109.94°). The homogeneous distribution of grains (average grain size = 1.717 μm) is studied via surface morphology demonstrating the feasibility of fabricating a high-density sample under experimental conditions. This compound shows ferroelectric and related properties, which have been experimentally verified by examination of the frequency-temperature dependence of capacitance, impedance, and other related behaviors. The variation of ac conductivity of the material under alternating current varies according to Jonscher's universal power law. The ferroelectric property of the material (Pr = 0.331C/cm2, Ec = 0.207 kV/cm) is demonstrated by the electric field-dependent polarisation (P-E loop) study. The temperature dependence of resistance yields a thermistor constant (β) and temperature coefficient of resistance (TCR), which may be useful for fabricating thermistor-based device applications. [ABSTRACT FROM AUTHOR]

The polycrystalline samples of gadolinium ortho-ferrite (GdFeO 3 ) modified barium titanate (BaTiO 3 ) ceramics have been prepared by a chemico-thermal route. The effect of sintering temperature on electrical (dielectric, impedance and conductivity) and magnetic characteristics of the material has been observed. The sintering temperature does not affect the crystal structure. With the increase in sintering temperature, the dielectric constant, loss tangent and the diffusive nature of the phase transition is found to increase. Impedance characteristics and transport properties of the material indicate a decrease in effective resistance of the sample with an increase in sintering temperature. The magneto-electric coefficient of the material was also found to decrease with increase in sintering temperature. [ABSTRACT FROM AUTHOR]

Abstract: Polycrystalline sample of Pb(Zr0.52Ti0.48)0.5(Fe0.5Nb0.5)0.5O3 (PZTFN) ceramics was prepared by a high-temperature solid-state reaction technique. Preliminary X-ray diffraction analysis confirms the formation of single phase compound with tetragonal crystal structure. The dielectric behavior of the material was studied in a wide frequency (100Hz–1MHz) and temperature (30–500°C) range. The relationship between dielectric constant ɛ r and temperature showed a single Curie transition temperature (T c =255°C), with as large a ɛ r value as 4200 at T c. A low value of dissipation factor (tan δ), as small as 0.04 up to temperature above than T c (frequency f =1kHz), with good insulating properties made the sample for prospective applications in microwave dielectric components and high-power-density capacitors. The higher diffusivity (γ∼1.6) value of the dielectric peak in the material indicates the greater disordering in the system. The signature of ac conductivity depending upon frequency and temperature exhibits the presence of different type of charge species. It is observed that oxygen vacancy plays an important role for high temperature conduction mechanism and dynamics of polarization of the system. [Copyright &y& Elsevier]

Abstract: The polycrystalline sample of LiBaFeWO6 was prepared by a high-temperature solid-state reaction technique. Preliminary structural analysis shows the formation of a new compound with an orthorhombic crystal structure at room temperature. The SEM micrograph shows the polycrystalline nature of the sample with different grain-size and inhomogeneous distribution. The temperature dependent dielectric and impedance behavior of the material was studied in a wide frequency (1kHz–1MHz) and temperature (30–480°C) range. The nature of electrical conduction and relaxation is supported by hopping mechanism of ions and oxygen vacancies. [Copyright &y& Elsevier]

In this article, detailed investigations on structural, dielectric, impedance, and leakage current characteristics of samarium modified bismuth titanate of chemical formula (Bi 3.9 Sm 0.1 Ti 3 O 12), prepared by cost-effective solid-state reaction technique (with 850 °C calcination and 900 °C sintering temperatures), have been discussed. The X-ray structural study has shown that the compound crystallizes in orthorhombic symmetry with the B2ab space group. SEM micrograph at room temperature displays the grains are uniformly distributed on the surface with a very small amount of voids. The electrical measurements of the compound were carried out by a phase-sensitive (LCR) meter over broad temperature (25 °C–400 °C) and frequency (1 kHz-1 MHz) ranges. The hysteresis loops between polarization (P) and electric field (E) at different temperatures show the existence of ferro-electricity in the compound. All the electrical characteristics have shown significant modification on even a small substitution (i.e., 10%) of trivalent rare earth element (i.e., samarium) in the bismuth site. The leakage current study at various temperatures shows the existence of Ohmic conduction in the compound. The value of leakage current makes the sample preferable for electronic devices. • Room temperature XRD analysis determines the orthorhombic structure of the compound with B2ab space group. • The SEM micrograph indicates that the grains are uniformly distributed with a few voids. • A high dielectric constant and low tangent loss makes the material suitable for device application. • The J-E characteristics of the sample indicate the Ohmic conduction along with the absence of the SCLC mechanism. • Ferroelectric behavior of the material is confirmed from the P-E hysteresis loop. [ABSTRACT FROM AUTHOR]

Abstract: Polycrystalline sample of Ca3Nb2O8 was prepared by a high-temperature solid-state reaction technique. X-ray diffraction (XRD) analysis confirms the formation of single-phase compound of hexagonal (rhombohedral) crystal structure at room temperature. Scanning electron micrograph of the material showed uniform grain distribution on the surface of the sample. Detailed studies of dielectric properties of the compound, studied in a wide frequency range (102–106 Hz) at different temperatures (25–500°C), exhibit a dielectric anomaly suggesting phase transition of ferroelectric–paraelectric and structural type at 300°C. Electrical properties of the material were analyzed using a complex impedance technique. The Nyquists plot showed the presence of bulk effect in the material in the studied temperature range. Studies of electrical conductivity over a wide temperature range suggest that the compound has negative temperature coefficient of resistance behavior. [Copyright &y& Elsevier]

Abstract: A polycrystalline sample of LiCa2V5O15 (LCV) was prepared using a mixed oxide method at low temperature (i.e., at 630 °C). X-ray structural analysis shows the single-phase formation of the compound in the orthorhombic crystal system at room temperature. A study on the surface morphology of the compound showed uniform grain distribution on the surface and in the bulk of the sample with less porosity. A dielectric anomaly suggests that the compound has a transition temperature at 274 °C. The activation energy, calculated from the temperature dependence of ac conductivity (dielectric data), of the compound was found to be 0.67 eV at 10 kHz. The nature of the variation of conductivity and value of activation energy in different regions, suggest that the conduction process is of mixed type (i.e., ionic–polaronic and space charge generated from the oxygen ion vacancies). [Copyright &y& Elsevier]

Abstract: Polycrystalline sample of Pb2Sb3LaTi5O18, a member of tungsten-bronze (TB) family, was prepared using a high temperature solid-state reaction technique. XRD analysis indicated the formation of a single-phase orthorhombic structure. The dielectric studies revealed the diffuse phase transition and the transition temperature found to be at 52°C. Impedance plots were used as tools to analyse the sample behaviour as a function of frequency. Cole–Cole plots showed Debye-type relaxation. The activation energy was estimated to be 0.634eV from the temperature variation of dc conductivity. The nature of variation of dc conductivity with temperature suggested NTCR behaviour. [Copyright &y& Elsevier]

Abstract: Polycrystalline samples of Pb0.9(La1−zFez)0.1(Zr0.65Ti0.35)0.975O3 [referred as PLFZT] (where z =0.0, 0.3, 0.5 and 0.7) have been synthesized by a high-temperature solid-state reaction technique. X-ray diffraction analysis suggests the formation of single-phase compounds with tetragonal structure. The dielectric studies of the compounds as a function of temperature (from room temperature (RT) to 600 K) at a frequency 10 kHz show that the compounds undergo a phase transition of diffuse type. Diffusivity studies of the phase transition of these compounds provided its value between 1 and 2, indicating the variation of degree of disordering in the system. Measurement of dc resistivity (ρ dc) as a function of temperature (RT to 600 K) at a constant biasing field dc 10 V/cm suggests that the compounds exhibit negative temperature coefficient of resistance (NTCR). The piezoelectric parameters as planar coupling coefficient, frequency constant and mechanical quality factor have been presented. [Copyright &y& Elsevier]

Single phase orthorhombic tungsten–bronze (OTB) ceramics of Pb2Bi3NdTi5O18 (PBNT) were prepared by a high temperature solid-state reaction method. Electrical impedance, phase angle, dielectric constant and dielectric loss have been measured in the frequency range 0.1 kHz–3 MHz in the temperature region 16–250 °C. Dielectric studies show relaxor behaviour with a diffuse phase transition having diffusivity parameter value 1.85. AC impedance analyses suggested the phase element to be capacitive. The Cole–Cole plot indicated high resistance of the sample at room temperature. The activation energy (Ea=0.63 eV) has been estimated from the temperature variation of DC resistivity. [Copyright &y& Elsevier]

A binary solid solution of Pb0.9(La1−ySby)0.1(Zr0.65Ti0.35)0.975O3 (PLSZT) was synthesized by a high-temperature solid-state reaction method, near the morphotropic phase boundary (MPB). Detailed studies of the dielectric permittivity (&epsiv;) and loss tangent (tanδ) of PLSZT ceramics as a function of temperature (30–400 °C) at 10 kHz suggest that the compounds exhibit a phase transition of diffuse type. The transition temperature (Tc) is found to increase with an increase in Sb concentration. The activation energy (DC and AC) of PLSZT was found to be very small (<0.1 eV), which is comparable to other ferroelectric oxides of the family. The decrease of DC resistivity of PLSZT with an increase in temperature suggests a negative temperature coefficient resistance (NTCR) behavior of the compound. [Copyright &y& Elsevier]

This investigation involves the synthesis and study of dielectric, structural and impedance properties of polycrystalline Bi(Ni 2/5 Ti 2/5 Fe 1/5)O 3 (symbolized as BNTF) nano-ceramic. The BNTF polycrystalline sample was fabricated through the use of a conventional solid-state reaction route. X-ray structural examination reveals that the parent compound (i.e., BiFeO 3) crystallizes in the rhombohedral structure (space group-R3c) while that the BNTF compound crystallizes in orthorhombic symmetry. The substitution of NiTiO 3 into BiFeO 3 enhances various properties and reduces electrical leakage current. The average crystallite size is calculated to be 29 nm. The room temperature textures and surface morphologies of the specimen were verified by field-emission scanning electron microscope, and show uniform grains distribution on sample surfaces. Dielectric parameters (constant and tangent-loss) and impedance spectroscopy parameters of NiTiO 3 modified BiFeO 3 compound were investigated over a wide temperature range (25–500 °C) at different frequency (25 kHz-500 kHz), which offers several interesting features of BNTF material suitable for further device applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Improved ε r and ac-conductivity of Sn-modified lead germanate. • Temperature-dependent dielectric and electrical properties. • Decreased E a and revealed conduction mechanism of PGSO at higher temperatures. • NTCR behavior of PGSO for high-sensitivity thermistors and sensors. • Thermistor constant (β) of 1662 K in 250 °C-300 °C. A solid-state reaction was used to synthesize the tin modified lead germanate: Pb 5 Ge 1.5 Sn 1.5 O 11 (PGSO). The composition was modified to enhance its dielectric and electrical properties. The PGSO sample was characterized by various analytical techniques, such as XRD for structural analysis and FTIR for additional structural information. The surface morphology and features of PGSO were examined by SEM, while its band gap was determined by UV–Visible-Diffuse Reflectance Spectroscopy absorbance spectra. The impedance, dielectric behaviour, AC conductivity, activation energy, and modulus of PGSO were also studied. The temperature dependence of the dielectric constant and AC conductivity showed an increase with increasing temperature. The electrical resistivity (R) decreased as the temperature increased from 100 °C to 300 °C, exhibiting a NTCR behaviour for PGSO sample, which could be applied as a high temperature thermistor and sensor, and could be used to fabricate a high sensitivity, low-cost thermistor. The circuit parameters such as bulk resistance (R b), frequency factor (n), and bulk capacitance (C b) were determined by fitting the Nyquist plot using an equivalent circuit (CQR)(CR). [ABSTRACT FROM AUTHOR]

• La 3 TiVO 9 , a compound of the Aurivillius family crystallizes in the orthorhombic crystal system. • La3+ decreases the oxygen vacancy and thus the loss tangent in comparison to similar compounds with Bi3+ ion. • The P-E loop is analyzed for polarization reverse due to ferroelectric and the conductivity based lossy dielectric nature. • La 3 TiVO 9 has high application potentiality in the dielectric industry. Detailed investigations of a new member of Aurivilius family La 3 TiVO 9 , fabricated by the mixed oxide reaction method, are found to crystallize in the orthorhombic crystal system. The prepared sample has a higher value of ε r ′ and lower value of tan ⁡ δ as compared to those of the reported ones of Bi 3 TiNbO 9 , and is thermally more stable. The Nyquist plots suggest the polarization from only grain contribution even up to 525 °C. The relaxor behavior and distribution of relaxation time are analyzed from the modulus spectroscopy. The nature of the field-dependent P-E hysteresis loop indicates the occurrence of ferroelectricity in the sample. Conductivity data indicate an activation energy of 0.98 eV for both DC conduction and relaxation processes and correlated barrier hopping model as the effective conduction process in the sample. [ABSTRACT FROM AUTHOR]

A ceramic composite of Bi 0.5 Na 0.5 TiO 3 (BNT) and CeO 2 (maintaining the Ce: Ti ratio of 20:80) has been synthesized by a standard mixed-oxide reaction method. The Rietveld analysis of X-ray diffraction pattern, backscattering scanning electron micrograph, energy dispersive X-ray spectroscopy, and Fourier transform infrared spectra reveal the formation of the two-phase composite (Bi 0.5 Na 0.5 Ti 0.94 Ce 0.06 O 3) 0.85 -(CeO 2) 0.15. The estimated optical band gap of the composite is found to be 2.72 eV. In the high-temperature range, the dielectric constant of the composite (4133 at 1 kHz) is significantly higher than that of BNT (1586 at 1 kHz). The static and infinite frequency dielectric constant and the relaxation distribution parameter for both the grain and grain boundary contributions have been determined from the Cole-Cole plot. The contribution of Debye-type relaxation for each of the grain and the grain boundary component and the DC conductivity to the loss tangent have been resolved. The fabricated composite has provided low dielectric loss and enhanced ferroelectric properties. Image 1 • Ceramic composite crystallizes with rhombohedral and Cubic Structure. • Dielectric parameters have been obtained from Cole-Cole Plot. • Resolution of Loss Tangent to Grain, Grain Boundary Relaxation and Conductivity. [ABSTRACT FROM AUTHOR]

• Colossal dielectric constant (CDC) observed for compositions x = 0.3, 0.4 and 0.5. • CDC originates due to the formation of internal barrier layer capacitor. • CDC in wide temperature range explained on the basis of multiple phase transition. • Relaxation mechanism analyzed from the Cole-Cole plot and Bode plot. Structural, microstructural, dielectric, multiferroic characteristics and relaxation mechanisms of (Ba 1- x Sm x)(Ti 1- x Fe x)O 3 samples with varrying compositions (x = 0.0–0.5) are reported in the present article. Standard crystal data and the Rietveld refinement results suggest tetragonal structure for all the compositions similar to the pure BaTiO 3. SEM, EDX and color mapping are used for the analysis of microstructural, compositional and elemental study. Impedance analysis is carried out using Nyquist plot. Relaxation mechanisms are analyzed from the complex permittivity Cole-Cole plot and the Bode plot. Colossal dielectric constant was observed over a wide temperature range for compositions x = 0.3, 0.4 and 0.5 due to the formation of internal barrier layer capacitors and the ferroelectric-paraelectric transitions of BaTiO 3 and magnetic transitions of SmFeO 3. The colossal dielectric response of these compositions makes them suitable for potential applications in microelectronic devices such as dynamic random access memory (DRAM) and on-chip capacitors. [ABSTRACT FROM AUTHOR]

BiHoZnCeO6, the double pervoskite was synthesized using a cost-effective solid-state reaction method. The structural evaluation of the double pervoskite, when carried out by using the X-ray diffraction pattern suggested an orthorhombic crystal geometry with non- centrosymmetry space group Pca21. The microstructural investigation on the above material is carried out with the help of a scanning electron micrograph. These SEM micrographs showed that the grains of varying sizes (0.5–2 μm) are uniformly distributed. The study of dielectric characteristics as a function of temperature and frequency revealed some interesting characteristics of the material. One such observation is the identification of ferroelectric transition temperature at 435 °C. The strong anomaly at 435 °C and the ferroelectric behavior of the material is further validated by the study of spontaneous polarization (the hysteresis loop). In the present communication, the detailed microstructural, dielectric (dielectric constant, tangent loss, and electric polarization), thermal and electrical (impedance, electrical modulus, conductivity) studies on bismuth holmium zinc ceranate is presented along with the existence of ferroelectricity. [ABSTRACT FROM AUTHOR]