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Soft ferrimagnetic spinel lithium based oxides were prepared with additives like V2O5 and Na2SiO3 and sintered with the efficient microwave sintering technique. Tetravalent metal ions substituents like Mn+4, Ti+4 were used to enhance the important properties like D. C. resistivity, saturation magnetization, permeability, hysteresis and dielectric behavior. The ferrites were sintered at different sintering temperatures viz., 900, 950 and 1000 °C for 10 min by microwave technique and by conventional technique at 1050 °C for 4h. X-ray diffraction (XRD) studied the structural behavior which confirmed the spinel characteristics, Scanning electron microscopy (SEM) and EDAX revealed the microstructural and elemental compositions respectively of the ferrites. The use of additives and the microwave sintering significantly influencing the microstructural behavior and subsequently on the electromagnetic properties could be observed. Studies of initial permeability and initial permeability loss found to remain nearly constant with change in frequency until at certain frequency they showed resonance behavior. The resonance frequency's dependence on the microstructures of the ferrites could be observed. Temperature dependence behavior of the dielectric parameters and the B-H loop traced from torroidal samples of the ferrites were studied. [ABSTRACT FROM AUTHOR]

The effect of simultaneous substitution of La3+ and Fe3+ ions on structural, dielectric, ferroelectric and piezoelectric properties of BaTiO3 was studied. Polycrystalline ceramic samples with composition Ba1-xLaxTi1-xFexO3 with x = 0, 0.005, 0.015 and 0.020 were prepared by the solid-state route and sintered at 1325°C. X-ray diffraction (XRD) analysis confirmed the single phase with tetragonal perovskite structure in all the prepared ceramics. Dielectric constant 'ϵ' and tangent loss 'tanδ' was measured as a function of temperature (25–200°C). The value of ϵ increases with an increase in La and Fe contents. A very small value of tanδ (<4%) was observed. The temperature coefficient of capacitance 'Tcc' was found to be around 10% for all the samples. PE hysteresis loops were recorded at room temperature for all samples. The maximum value of ϵ and piezoelectric coefficient 'd33' was found to be 3735 (at 30°C, 100 kHz) and 140pC/N, respectively for x = 0.020. [ABSTRACT FROM AUTHOR]

In this work, magnetoelectric properties of a co-sintered bilayered composite of non-lead based piezoelectric 0.97(Bi0.5Na0.5TiO3)-0.03(K0.47Na0.47Li0.06Nb0.74Sb0.06Ta0.2O3) and magnetostrictive Co0.6Zn0.4Fe1.7Mn0.3O4 are presented. Similar optimal sintering conditions of the individual components lead to a very clean interface as evidenced in the scanning electron microscopy, angle dispersive X-ray diffraction, and energy-dispersive X-ray (EDX) results. Clean interface results in strong intimate mechanical coupling between both components and causes a maximum transfer of induced strain, leading to a large magnetoelectric coupling ~142 mV/cm.Oe measured in longitudinally magnetized-transversely polarized configuration (L-T mode). Remnant polarization ~32 μC/cm2, remnant magnetization ~0.50 emu/g, and sufficiently high self biased magnetoelectricity ~135 mV/cm Oe (L-T mode) were observed for this composite. [ABSTRACT FROM AUTHOR]

We report the effect of processing parameters such as (1) uniaxial and (2) isostatic pressings on ferroelectric behavior of lead zirconate titanate (PZT) having Zr/Ti ratio 65/35. The effect of temperature (-125–250 °C) on pinched loop characteristics of uniaxially pressed PZT is also reported. Polycrystalline ceramic samples were synthesized by solid-state reaction technique and sintered at 1250 °C. The density was estimated to be 7.63 and 7.58 g/cc for the uniaxially and isostatically pressed samples, respectively, prepared by conventional ball milling. X-ray diffraction analysis confirmed single phase formation with rhombohedral structure. All samples pressed uniaxially and isostatically showed pinched hysteresis loops at room temperature that disappear at higher temperatures. The remnant polarization (Pr) and coercive field (Eo) for the uniaxially pressed samples become well defined in magnitude and shape at higher measurement temperatures below phase transition temperature (Tc), but at low temperatures a distorted-loop-like structure was observed indicating low polarization properties. The effect of ferroelectric switching cycles on the PZT samples with and without annealing in oxygen is also discussed. [ABSTRACT FROM AUTHOR]

In this work, room temperature magnetoelectric properties of (0−3) particulate composites of non lead based piezoelectric BNTKNNLTS [0.97(Bi 0.5 Na 0.5 TiO 3 )–0.03(K 0.47 Na 0.47 Li 0.06 Nb 0.74 Sb 0.06 Ta 0.2 O 3 ) and magnetostrictive CZFMO (Co 0.6 Zn 0.4 Fe 1.7 Mn 0.3 O 4 ) are presented. Composite samples of (1- x )(BNTKNNLTS)- x (CZFMO) , with x =0.1 and 0.5, are synthesized by solid state reaction route. X-ray diffraction confirms the single phase formation of parent phases and the presence of two phases in the composites. Similar sintering conditions of the two individual components lead to optimal ferroelectric and ferromagnetic properties in the composites. A large self-biased magnetoelectric (ME) coupling ~74 mV/cm.Oe for the sample with x =0.1 (measured in longitudinally magnetized-transversely polarized configuration) is observed at room temperature. [ABSTRACT FROM AUTHOR]

In this paper, we are reporting structural, dielectric, ferroelectric and magnetic properties of polycrystalline composites (ferrite and ferroelectric) of PZT (PbZr0.55Ti0.45O3) + CNFO (Co0.8Ni0.2Fe2O4). The sample with composition x CNFO + (1-x) PZT (x = 0.00, 0.05, 0.10, 0.15 and 1.00) were prepared using the solid state double sintering method. Here the ratio x: (1-x) of two components is by weight. X-ray diffraction (XRD) studies show that lattice constant and tetragonality decreases with increasing ferrite content. Dielectric constant was found to decrease with increase in amount of CNFO. The value of tangent loss (tanδ) was reasonably low (< 0.04) for all the samples. Ferroelectric and ferrimagnetic behavior was confirmed by observing P-E and M-H hysteresis loop, respectively. The room temperature magnetoelectric coupling coefficient (α = dE/dH) was measured as a function of applied DC magnetic field. The value of α was observed to be maximum (855 μV/(cm.Oe)) at DC magnetic field of 1.7 kOe for sample with 5% CNFO. Value of piezoelectric coefficient ‘d33’ decreases from 133 to 60 pC/N. [ABSTRACT FROM PUBLISHER]

Material series with compositional formula BaPbTiZrO (0 ≤ x ≤ 0·20, in steps of 0·05) were prepared by conventional solid state method. All the samples were subjected to X-ray diffraction (XRD) studies and found to be single phase with perovskite structure. SEM measurements were done in order to collect micro-structural information. Different transition temperatures were found to depend on the Pb content. Tetragonality ( c/a) and Curie temperature ( T) increase with increase in lead content x. Dielectric properties were studied as a function of temperature and frequencies. [ABSTRACT FROM AUTHOR]

The composites consisting of Mn doped Ni0.8Zn0.2Fe2O4 and Zr substituted Ba0.9Sr0.10TiO3 (BST) where Zr varies from 0.00 to 0.16 in steps of 0.04 were prepared by conventional solid state reaction route. The existence of both phases was confirmed by the XRD patterns and the lattice parameters for each composition were calculated. The dielectric parameter such as dielectric constant and dielectric loss were measured as a function of frequency and temperature. As we increase the Zr in ferroelectric phase, the dielectric loss of composite samples decreases up to 1% from 8%, and also Tmax decreases towards room temperature. Observation of ferroelectric and magnetic hysteresis loops for all samples confirms the electric and magnetic nature of the samples. [ABSTRACT FROM AUTHOR]

In the present work, we are reporting the effect of Mn doping on the structural, dielectric and ferroelectric properties of Ba0.80Pb0.20Ti0.90Zr0.10O3. Samples were prepared by solid state reaction route. X-ray diffraction analysis confirmed the compositions to be single phase. Dielectric properties were studied as a function of temperature and phase transition temperature (Tc) was determined. Ferroelectric behaviour was studied in detail as a function of temperature. Mn doping was found to improve temperature stability of the material. [ABSTRACT FROM AUTHOR]

Ceramics with compositional formula Ba0.80Pb0.20Ti1-xZrxO3; x = 0.00, 0.02, 0.04, 0.06, 0.08 and 0.10 were synthesized by conventional solid state reaction method. The single phase with perovskite structure was confirmed by X-ray diffraction analysis for all the samples. The tetragonality was found to decrease with increasing zirconium content. The room temperature dielectric properties for all the samples were investigated in the frequency range 20 Hz to 1 MHz. It is observed that the increasing of zirconium content results in an increase in dielectric constant. The dielectric constant was found to decrease with increase in frequency. [ABSTRACT FROM AUTHOR]

Due to its important applications, there has been a great deal of interest in the fabrication as well as in the electrical and ferroelectric properties of barium titanate (BT)-based ceramics. The dielectric and ferroelectric properties of BT depends on the fabrication techniques and compositional modifications. In conventional solid state reaction technique, the main problem in fabrication of ceramics includes contamination from the tearing and wearing of balls and walls of the milling container, time and power consumption. Various attempts has been made in reducing the time and power consumption. Ultrasonic mixing of raw materials to prepare desired material is a method to reduce contamination and time & power consumption. X-ray diffraction confirms the existence of single phase. Comparative study of the dielectric properties shows the better stability of dielectric constant with frequency and temperature in case of barium titanate prepared using ultrasonically mixing. [ABSTRACT FROM AUTHOR]

Polycrystalline ceramics samples having compositional formula PbZr0.588Ti0.392Fe0.01Nb0.01O3 and Pb0.98Sm0.02Zr0.588Ti0.392Fe0.01Nb0.01O3 were prepared by traditional solid state route. Sintering was carried out at 1250°C in closed alumina crucibles in lead rich atmosphere. XRD analysis confirmed formation of tetragonal perovskite structure and tetragonality was found to decrease with Sm substitution. In order to study microstructure, SEM micrographs were recorded on freshly broken pieces. The grain size was observed to decrease with Sm addition. P-E hysteresis loops were recorded at different temperatures for investigating ferroelectric properties. Sm substitution improves squareness and remanence. [ABSTRACT FROM AUTHOR]

The article reports on the improvements that arise in the electrical and structural properties of Li-Mn-Ti ferrite with the formula Li0.60Mn0.1Ti0.1Fe2.20O4 using novel microwave (MW) processing. It says that the formation of single phase spinel structure in both samples was confirmed by X-ray diffraction. It adds that the studies of dielectric properties as temperature function show the stability of dielectric properties with temperature.

Here we report the investigations on Sm-substituted PZTFN (Pb1-xSmxZr0.588Ti0.392Fe0.01Nb0.01O3) (where x = 0, 0.02, 0.04, 0.06, 0.08, 0.10) polycrystalline solid solutions fabricated by solid-state reaction method. XRD analysis shows all the samples to be single phase with tetragonal structure. Dielectric measurements were carried out in the temperature range 30°C–400°C at different frequencies in the range 100 Hz to 100 kHz. From the temperature variation of dielectric constant (ε), Curie temperature (TC) was determined which was found to decrease with increasing x. The room temperature dielectric constant (εRT) initially increases with increasing x and then starts decreasing. Dielectric loss improves with Sm-doping. [ABSTRACT FROM AUTHOR]

Pb0.76-3x/2LaxCa0.24Mn0.02Ti0.98O3 (PLCT), x=0–0.08 (in steps of 0.02), ceramics were prepared by conventional mixed oxide technique. The samples were sintered at an optimized temperature of 1150°C. Phase and microstructural analysis were carried out using X-ray Diffraction (XRD) and scanning electron microscope (SEM) to study the effect of lanthanum on PCT ceramics. Both experimental and theoretical densities for all the samples were also determined. Phase analysis shows the single-phase material with tetragonal structure and the decrease in tetragonality is observed with the increase in the amount of lanthanum in the base composition. Detailed dilatometric investigations were performed in order to study the shrinkage behaviour and dominating shrinkage mechanism in the present system. [ABSTRACT FROM AUTHOR]

To explore the magnetoelectric effect in lead free bulk ceramics, solid solutions of BaZr0.05(FexTi1-3x/4)0.95O3 have been synthesized using conventional solid state reaction route with x = 0.000 to 0.020 in steps of 0.005. A small amount of Fe content shows an immense effect on properties of barium zirconium titanate. Room temperature X-ray diffraction studies substantiate the formation and purity of these polycrystalline samples in an orthorhombic crystal system. Temperature dependent dielectric study revealed a decrease in ferroelectric Curie temperature with a decrease in dielectric constant values as x varied from 0.000 to 0.020. Ferroelectricity is still maintained and well saturated loops are observed with Fe substitution at these levels; although the remnant polarization Pr values decrease substantially with increasing Fe content. The best value of magnetoelectric coupling coefficient (α) at room temperature is found to be 145.30 mV/cm.Oe for x = 0.015 sample. In conclusion, in a non-Pb based simple perovskite system a reasonably large magnetoelectric coupling is demonstrated. [ABSTRACT FROM AUTHOR]

Abstract: A modified lead zirconate stannate titanate system (PZST) has been studied for shape memory effect. Addition of magnesium niobate (MN) slows down the dipole relaxation process, leading to increased (∼3-fold improvement) remnant strain in the PZST system (0.99PZST–0.01PMN). Room temperature X-ray diffraction patterns before poling (antiferroelectric (AFE) tetragonal) and after poling (ferroelectric (FE) rhombohedral), clearly demonstrate that the transition to the ferroelectric phase is stable even in the absence of any electric field. A small applied electric field (∼1.7kV/cm) in the opposite direction was required to bring the sample back to its original shape. Field-induced strain butterfly loops taken at 50Hz show that the material response time is quite small. [ABSTRACT FROM AUTHOR]

Abstract: Nanocrystalline lithium zinc ferrites substituted with cobalt were synthesized by the citrate precursor method. X-ray diffraction was used to confirm the spinel phase. Mössbauer studies at room temperature were carried out to study the effect of cobalt concentration on the various hyperfine interactions. Variation of the saturation magnetization with respect to composition was discussed. The result shows some anomalous behaviour when cobalt is substituted to lithium ferrite in presence of zinc. [Copyright &y& Elsevier]

Abstract: Polycrystalline samples of the nominal composition Pb0.76−x Sm x Ca0.24Ti0.98Mn0.02O3 were prepared using a solid state reaction technique. Single-phase formation was checked through X-ray diffraction. Dielectric properties were studied as a function of frequency and temperature. The transition temperature determined from dielectric constant vs. temperature plots was found to decrease with increasing Samarium substitution. Poling field was optimized to achieve maximum piezoelectric properties. Piezoelectric coefficients e.g. d 33, d 31, g 33, g 31, g h, d h, k t and k p were measured. The experimental results successfully showed that samarium substitution is helpful to obtain a much higher value of thickness electromechanical coupling coefficient, k t (∼57%) while maintaining a smaller planar electromechanical coupling coefficient, k p in PCT ceramics. [Copyright &y& Elsevier]

A comparative study is reported on the ferroelectric ceramics with compostional formula Ba 0 · 98 La 0 · 02 Ti 0 · 98 Fe 0 · 02 O 3 (BLTF1) and Ba 0 · 97 La 0 · 02 Ti 0 · 98 Fe 0 · 02 O 3 (BLTF2; valency compensated). The samples were prepared by solid state route and sintered in air at 1325 °C for 4 h. The X-ray diffraction analysis confirmed the formation of tetragonal perovskite phase. The prepared samples were characterized for their dielectric and ferroelectric properties at different temperatures at 1, 5, 10 and 100 kHz. Enhancement in ferroelectric properties (P r = 11.25 μC/cm2, E c = 9.05 kV/cm) was observed in BLTF2 ceramics as compared to BLTF1 ceramics (P r = 6.53 μC/cm2, E c = 9.35 kV/cm) along with the observation of electrocaloric effect. The value of piezoelectric coefficient 'd 33 ' was found to be 140 pC/N and 163 pC/N for BLTF1 and BLTF2 samples respectively. The present investigations show that the valency compensation method can improve the ferroelectric properties of the ferroelectric ceramics thereby making them more suitable for different applications. [ABSTRACT FROM AUTHOR]

We are reporting here, the studies of the structural, dielectric, ferroelectric and magnetic properties of magnetoelectric composites of La modified lead zirconate titanate (PLZT) and Ni modified cobalt ferrite (CNFO) with compositional formula x Co 0.8 Ni 0.2 Fe 2 O 4 +(1− x ) Pb 0.99625 La 0.0025 Zr 0.55 Ti 0.45 O 3 ( x =0.00, 0.05, 0.10, 0.15 and 1.00 by weight) prepared by the solid state reaction method. Coexistence of both the phases in composites was confirmed by X-Ray diffraction technique. The microstructure and average grain size were determined from Scanning Electron Micrograph (SEM) in backscattered mode. Both the phases could be observed clearly. The variations of dielectric properties with frequency and temperature were also studied. P–E and M–H hysteresis measurements were carried. Magnetoelectric coupling (ME) coefficient for samples with x =0.05 and 0.10 were measured as a function of DC magnetic field. Maximum value of ME coefficient (1.2 mV/cm Oe) and piezoelectric coefficient (96 pC/N) for x =0.05 were observed. [ABSTRACT FROM AUTHOR]

In the present work, we have attempted to reduce the effect of coring effect in the titanate ceramic system BaTi 4 O 9 (BT4) by doping it with Mn 4+ . The microwave dielectric BaTi 4 O 9 ceramics doped with 0, 0.5 and 1.0 mol% Mn 4+ were synthesized by conventional ceramic processing route. The XRD studies confirmed a single phase crystalline structure for all the ceramic samples studied. The SEM micrographs of the ceramics reveal a microstructural change leading towards a more uniform grain size distribution as the Mn 4+ content increases to 1.0 mol%. In the low frequency region (100 Hz to 1 MHz), the temperature stability of dielectric properties exhibits a marked improvement with the increasing amount of Mn 4+ in the ceramic system. In the microwave frequency region (9.3 GHz), Q -factor increases from 11,625 GHz to 46,500 GHz for BaTi 4 O 9 ceramic doped with 1.0 mol% Mn 4+ . The present paper reveals that the commonly observed degradation of dielectric properties due to coring effect in the BaTi 4 O 9 ceramic system can be controlled by doping it with an appropriate quantity of Mn 4+ . [ABSTRACT FROM AUTHOR]

In the present article, lanthanum substituted modified PZT (Pb,La)(Zr,Ti,Fe,Nb)O 3 , (Zr:Ti=60:40) PLZFNT bulk ceramics were prepared by solid state reaction technique. The concentration of La 3+ was varied from 0 to 1 mol%. X-ray diffraction (XRD) analyses of these samples suggest the formation of good quality and homogeneous single phase pervoskite compounds. Lattice parameters (a & c) were found to decrease with increase in La 3+ concentration. The dielectric properties of PLZFNT were measured using LCR meter as a function of temperature and frequency. It was found that dielectric properties of the samples are highly dependent on the La 3+ content. Room temperature dielectric constant was found to be increased, whereas the Curie temperature decreased with La 3+ content. [ABSTRACT FROM AUTHOR]

In present study we have prepared ferroelectric BaZrxTi1-xO3 (x = 0.05) ceramic by conventional solid state reaction route and studied its electrical properties as a function of temperature and frequency. X-ray diffraction (XRD) analysis shows single-phase formation of the compound with orthorhombic crystal structure at room temperature. Impedance and electric modulus spectroscopy analysis in the frequency range of 40 Hz-1 MHz at high temperature (200-600 °C) suggests two relaxation processes with different time constant are involved which are attributed to bulk and grain boundary effects. Frequency dependent dielectric plot at different temperature shows normal variation with frequency while dielectric loss (tanδ) peak was found to obey an Arrhenius law with activation energy of 1.02 eV. The frequency-dependent AC conductivity data were also analyzed in a wide temperature range. [ABSTRACT FROM AUTHOR]

Abstract: The perovskite Pb(1−x)Ba x Zr0.55Ti0.45O3 material (x=0.00, 0.01, 0.02, 0.03, 0.05, and 0.07) was synthesized by solid state reaction route. Green bodies were sintered at 1250°C. All samples were subjected to X-ray diffraction analysis and they were found to be in single phase. Dielectric properties were studied as a function of temperature and frequency. Ferroelectric properties were studied as a function of temperature. Remnant polarization, saturation polarization and coercive field were determined for all the samples using ferroelectric loops. Piezoelectric properties such as d 33 and electromechanical coupling factor (k p) were also measured at room temperature for all samples. [Copyright &y& Elsevier]

Abstract: Composites having general formula 0.1Ni0.8Zn0.2Fe2O4–0.9Pb1−3x/2Sm x Zr0.65Ti0.35O3 with x=0, 0.01, 0.02 and 0.03 were synthesized by a conventional solid state reaction route. X-ray diffraction analysis was carried out to confirm the coexistence of individual phases and microstructural study was done by using a scanning electron microscope. Dielectric properties were studied as a function of temperature and frequency. To study ferroelectric and magnetic ordering in composite samples, P–E and M–H hysteresis loops were recorded respectively. Maximum magnetoelectric coupling coefficient of 22.5mV/cmOe was observed for sample with x=0.03. A significant improvement in dielectric, ferroelectric, piezoelectric and magnetoelectric properties was observed for Sm substitution. [Copyright &y& Elsevier]

Room temperature and atmospheric pressure assisted hydrogenation of aromatic nitro compounds is achieved with a high proficiency over Schiff base Pt(II) complex supported montmorillonite. Usually hydrogenation reactions require severe conditions to crop up. However, our catalyst could alter these extremities exhibiting excellent yields with 100% selectivity. The catalyst was prepared by intercalating Schiff base Pt(II) complex into montmorillonite by simple cation exchange mechanism. The intercalation of the complex inside the clay matrix was supported by various characterization techniques like X-ray diffraction, thermogravimetric and differential thermogravimetric analysis, BET surface area measurement, UV–vis diffuse reflectance spectroscopy, Fourier transform infrared spectroscopy (FT-IR), and atomic absorption spectroscopy. The stability of the catalyst during the course of the reaction was confirmed from its post catalytic FT-IR analysis. The catalyst could be reused three times without noticeable loss of its catalytic activity. [ABSTRACT FROM AUTHOR]

Abstract: Lanthanum modified Ba0.80Pb0.20Ti0.90Zr0.10O3 (BPZT) ceramics with composition Ba0.80−x La x Pb0.20Ti0.90Zr0.10O3; x =0–0.01 in steps of 0.0025 were prepared by conventional solid state method. All the samples were sintered at 1325°C after compacting in circular discs. Detailed structural and ferroelectric properties were carried out for sintered specimens. X-ray diffraction analysis for all the sintered specimens shows tetragonal structure with perovskite. Coercive field (E c) and remanent polarization (P r) to spontaneous polarization (P s) ratio (P r/P s) was found to decrease with increase in temperature. P r/P s ratio was found to decrease with increase in x, except x =0.0025. [ABSTRACT FROM AUTHOR]

Abstract: Barium titanate is one of the most studied ferroelectric materials which has been used in various forms, e.g. bulk, thin and thick films, powder, in a number of applications. In order to achieve a material with desired properties, it is modified with suitable substituents. Most common substituents have been strontium, calcium and zirconium. Here, we report studies on lead and zirconium substituted barium titanate. The material series with compositional formula Ba0.80Pb0.20Ti1−x Zr x O3, with x varying from 0 to 0.1, was chosen for investigations. The material was synthesized by solid-state reaction method. Reacted powders compacted in the form of circular discs were sintered at 1300°C. All the samples were subjected to X-ray diffraction (XRD) analysis and found to have single phase perovskite structure. Dielectric behavior was studied as a function of frequency and temperature. Curie temperature (T c) was found to decrease with increasing x. [Copyright &y& Elsevier]

Abstract: In this paper we are reporting a systematic study on ferroelectric properties of lanthanum (La) substituted modified lead zirconate titanate (PLZFNT) ceramics which were fabricated by mixed oxide process. La contents were varied in between 0 and 0.01 in steps of 0.0025. The X-ray diffraction study shows single phase for all samples. Silver electrode was deposited on flat surfaces of sintered discs for P–E (polarization vs. electric field) measurements. All compositions exhibited well-defined ferroelectric behavior at room temperature. Hysteresis loops were also recorded at different temperatures for all the compositions which showed typical variation of ferroelectric nature. The PLZFNT composition with 1mol% of La showed the best retention behavior. The results are discussed. [Copyright &y& Elsevier]

Abstract: Here, we report dielectric behaviour of lanthanum substituted Ba0.80Pb0.20Ti0.90Zr0.10O3 (BPZT) ceramics. The material series with compositional formula Ba0.80− x La x Pb0.20Ti0.90Zr0.10O3 (BLPZT) with x varying from 0 to 0.01 in the steps of 0.0025 was chosen for investigations. The material was synthesized by solid state reaction method. Reacted powder compacted in form of circular discs were sintered at 1325°C. All the samples were subjected to X-ray diffraction (XRD) analysis and found to be single phase. Dielectric behaviour was studied as a function of frequency and temperature and Curie temperature (T c) was determined. T c was found to decrease with increasing x. The details are discussed and presented in this paper. [Copyright &y& Elsevier]

Abstract: Samarium modified lead zirconate titanate (PSZT: Pb1−x Sm x (Zr0.65Ti0.35)O3: x =0, 0.02, 0.04, 0.06) ceramics were synthesized by solid state ceramic route. XRD shows single-phase formation with rhombohedral structure up to x =0.04. With Sm—substitution, the grain size first increases up to x =0.02 and then decreases. A metal/ferroelectric/metal (MFM) structure was made by depositing gold electrode on the flat surfaces for electrical measurements. All samples show normal ferroelectric behaviour, however, a squareness of P–E loop (polarization vs. electric field) was observed to increase with Sm content. Higher electromechanical coupling coefficients (K p and K t) have been achieved for the PZT with 6mol% Sm substitution and having fine grain size. [Copyright &y& Elsevier]

Abstract: BST thin films are grown by pulsed laser deposition technique at different temperatures and different oxygen deposition pressures. X-ray diffraction studies confirm the perovskite phase of the films. From the ɛ′–V characteristic tunability is calculated and the films grown at lower oxygen deposition pressure is found have higher tunability which is explained in terms of stress developed in the film and oxygen vacancies formed during deposition. The ɛ′–V variation is explained in terms of Devonshire''s phenomenological theory. [Copyright &y& Elsevier]

Solid solution of 32 mol% of Lead Titanate in PMN–PT system has been prepared by columbite precursor method. Room temperature X-ray diffraction study reveals the formation of perovskite phase with tetragonal structure. Dielectric measurements have been carried out at different frequencies (0.1 kHz–1 MHz) as a function of temperature (RT to 235 °C). The phase transition was found to be of diffused type. The polarization studies show ferroelectric nature of the material with a high value of remnant polarization (Pr) ∼21 μC/cm2 and spontaneous polarization (Ps) ∼29 μC/cm2. Strain versus electric field (S–E) behavior shows piezoelectric nature of the material with high value of maximum strain 0.14% at 60 kV/cm. Pyroelectric coefficient at room temperature has been found to be 3×10−2 μC/cm2 K. [Copyright &y& Elsevier]

High density Ba 0.80 Pb 0.20 TiO 3 (BPT) ceramics were successfully prepared by using the microwave sintering technique, which helps in reduction of time and energy consumption that is quite large in normal conventional technique. X-ray Diffraction (XRD) study showed the single-phase formation with tetragonal structure. Dielectric study demonstrated sharp peak in dielectric versus temperature plots and high value of the T c as compared to that observed for samples prepared by conventional technique. The microwave sintering technique rendered drastic improvement in piezoelectric properties. The piezoelectric charge coefficient ‘ d 33 ’ was obtained to be 157pC/N as compared to 130pC/N in case of conventionally sintered sample respectively. [ABSTRACT FROM AUTHOR]

Li–Zn–Ti ferrite substituted with vanadium having the general formula Li0.5+tZn0.2Ti0.2VtFe2.1-2tO4 with 0.00≤t≤0.25 in steps of 0.05 were synthesized by the standard ceramic technique. X-ray diffraction (XRD) analysis showed all the samples to be single-phase with spinel structure. The variation of the lattice parameter with vanadium concentration is reported. The density of the samples has been studied as a function of composition. Magnetic properties such as Curie temperature (Tc), saturation magnetization (4πMs) were measured and were found to decrease with compositional parameter x. The mechanisms involved are discussed. [Copyright &y& Elsevier]