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High energy density is the goal pursued by energy storage dielectric capacitors. Lead-based antiferroelectric ceramics are the most promising material system. Herein, the improved recoverable energy storage of 14.5 J/cm3 and efficiency of 77.1 % are obtained at x = 0.02 in Ca2+-modified Pb0.97-xCaxLa0.02(Zr0.93Sn0.05Ti0.02)O3 (PCLZST) antiferroelectric ceramics, which are fabricated by the tape-casting method. It is proved that the partial substitution of Ca2+ to Pb2+ at A-site can effectively strengthen the antiferroelectricity due to the reduced tolerance factor. Besides, the addition of Ca2+ can refine the grains and increase the breakdown strength, up to 448 kV/cm vs 376 kV/cm for PLZST ceramics. In addition, the discharge energy density and time are 11.6 J/cm3 and 5.09 μs, respectively. These characteristics indicate that Pb0.95Ca0.02La0.02(Zr0.93Sn0.05Ti0.02)O3 ceramic is a potential energy storage material for pulsed power systems.

Electrocaloric effect (ECE) is considered well applicable in the field of next generation solid state refrigeration technology. In this article, the structural properties and ECE response were altered and optimized by tailoring the Zr/Ti molar ratio in (Pb0.94La0.04)(ZrxSn0.30Ti0.70-x)O3 (x = 0.54, 0.52, 0.50 and 0.48) polycrystalline ceramics. Multiple phase transition behaviors including antiferroelectric (AFE) state to ferroelectric (FE) state transition under applied electric field, depolarization phase change behavior and AFE state to paraelectric state (PE) transition were observed, and their effects on the ECE response were investigated in detail. Significant improvement of ECE adiabatic temperature change of 1.04 K at room temperature (30 °C) was obtained by Maxwell method in (Pb0.94La0.04)(Zr0.52Sn0.30Ti0.18)O3 bulk ceramic through AFE→FE phase transition, while the highest ΔT of 2.73 K with electrocaloric strength (ΔT·ΔE−1) of 0.039 K cm kV−1 were observed in (Pb0.94La0.04)(Zr0.50Sn0.30Ti0.20)O3 bulk ceramic at temperature close to its Curie peak. The high ECE temperature change and ECE strength make them to be candidates for using in next generation solid-state refrigeration device.

The applications of antiferroelectric (AFE) materials in miniaturized and integrated electronic devices are limited by their low energy density. To address the above issue, the antiferroelectricity of the reinforced material was designed to improve its AFE-ferroelectric (FE) phase transition under electric fields. In this present study, the composition of Zr4+ (0.72 A) and Ti4+ (0.605 A) at B-site of Pb0.97La0.02(ZrxSn0.05Ti0.95-x)O3 ceramics with orthogonal reflections are synthesized via the tape-casting method. These ceramics are modified to enhance their antiferroelectricity by reducing their tolerance factor. A recoverable energy storage density Wrec 12.1 J/cm3 was obtained for x = 0.93 under 376 kV/cm, which is superior value than reported until now in lead-based energy storage systems. Moreover, the discharge energy density can reach 10.23 J/cm3, and 90 % of which can be released within 5.66 μs. This work provides a new window and potential materials for further industrialization of pulse power capacitors.

Here, we present a collective prospective application that includes electrocaloric effect, thermal energy harvesting and energy storage density in Eu3+and Nb5+co-substituted Na0.5Bi0.5TiO3ceramics. To understand the structural property impact on desired properties, here presented the clear phase evaluation quantitatively with different phase coexistence over structural ambiguity of duel structural phase models. The induced adiabatic temperature change (ΔT) of these specimens reflects the significant change in entropy(ΔS) over a wide temperature range. The obtained change in ΔT evaluated @ 60 kV/cm was found to be nearly 0.4 K for these specimens. The pyroelectric energy harvesting property was investigated in detail with the help of the Olsen cycle. The estimated energy storage density as well as efficiency was enhanced greatly with substitution of Nb concentration as W r e c = 1.58 J/cm3 and η = 95(%) for NBET-Nb2 ceramics. The materials with multiple functionalities are considered to be an open window in the field of electronic devices, optoelectronics and solid state refrigerator applications.

In addition to energy storage density (Wrec) and energy efficiency (ƞ), electrical fatigue characteristic is also an important factor affecting the performance of anti-ferroelectric (AFE) capacitors. The main impacts of electrical fatigue characteristic are strain and thermal shock. The AFE ceramic materials will undergo AFE-FE phase transition, when the applied electric field is high enough. This process is usually accompanied by huge electric-field-induced strain, which results in the fatigue phenomenon during switching cycles. Meanwhile, low ƞ will lead to heat accumulation effect during working cycles. However, researches on these aspects are very limited for AFE capacitors. In this work, the (Pb0.96-1.5xBa0.04Lax)(Zr0.65Sn0.3Ti0.05)O3 (x = 0.02, 0.03, 0.04, 0.05) AFE ceramics with low electric-field-induced strain and high ƞ are obtained by regulating the content of La. The Pb2+ creates vacancies in A-sites crystal structure by introducing La-ions can reduce the strain and difference between AFE-FE (EF) and FE-AFE (EA), thereby improving ƞ simultaneously. As a result, the PBLZST ceramics exhibit a maximum Wrec of 4.44 J cm−3 and a high ƞ of 88.8% under 170 kV cm−1 when La3+ content of x = 0.03. The Wrec and ƞ fluctuate within 4.4% and 2.5% respectively after 5000 working cycles, which demonstrates the excellent anti-fatigue characteristic related to low electric-field-induced strain (0.26%) of the sample. Besides, these ceramics have a discharge energy density (Wdis) value as high as 4.22 J cm−3 under the field 170 kV cm−1, which indicates the amount of energy that can actually be released. Those advantages illuminate the PBLZST ceramics (x = 0.03) are beneficial to the practical application of AFE capacitors.

Here, in this paper, we have reported the structural, microstructural, optical, ferroelectric and magnetic properties of Nd and W/Co co-substituted Bi4NdTi3−2x(W/Co2)xFeO15 (0.00 ≤ x ≤ 0.15) 4-layered Aurivillius multiferroic ceramics. These ceramics were prepared by conventional high-temperature solid-state reaction method. The room temperature (RT) X-ray diffraction (XRD) and Raman studies revealed that, these ceramics exhibits a pure orthorhombic structure with A21am space group. The surface morphology of these ceramic studies confirmed the formation of randomly oriented grains as non-uniform in size. Further, W/Co2 substitution in BNFT revealed the presence of asymmetrical shaped internal nano-size domains. The band gap of the ceramics was calculated and found to be decreased upon with increasing the concentration of W/Co2. All compounds exhibited improved P–E loops with unsaturated polarization upon substitution with enhance polarization and reduced coercive field. It was found that with higher substitution levels x ≥ 0.10 adversely affected the ferroelectric characteristics. The magnetic measurement revealed that Nd and W/Co co-substitution induced a strong ferromagnetic interaction via Fe3+–O–Co2+/3+ coupling. The high-temperature magnetization studies revealed the Curie temperature (TC) enhances as the W/Co2 concentration increase. Henceforth, the observed outcomes are emphasized for designing new single-phase room temperature multiferroics in future magnetoelectric applications.

Lanthanum (La)-modified 0.93(Bi0.5−xLaxNa0.5TiO3)–0.07(BaTi0.96Zr0.04O3) (0.00 ≤ x ≤ 0.08) (Abbreviated as BLNT-BZT) ceramics were synthesized (close to MPB) by using conventional solid state route. The structural phase purity of ceramics was confirmed by using room temperature (RT) X-ray diffraction. The structural phases coexistence was analyzed with different duel phase model and bring out the amount of phase contribution quantitatively with the help of Rietveld refinement technique. The X-rays diffraction studies revealed that coexisting of minor tetragonal (P4mm) phase evolution along with major monoclinic structural (Cc) phase. Moreover, the above affirmation was clarified from Raman studies, observed that TiO6 reflection at 500–600 cm−1 splitting occurs resides the presence of MPB of ceramics. With the substitution of La in BNT–BZT induces the gradual change in the average grain size and non-uniform distribution was observed from the surface morphology. The dielectric anomalies of these BLNT-BZT ceramics show broad dielectric anomaly near the maximum dielectric constant, which reflects the diffuse phase transition behavior. The RT P-E loops were observed in slim and slanted shape, replicates the enhanced properties due to the phase additive behavior near the MPB.

Herein, we present comprehensive investigations of the optical and electrical properties of Nd3+ substitution in sodium bismuth titanate ceramics (NBNT) with varying Nd3+ concentration. The room temperature photoluminescence (PL) emission for both unpoled and poled samples is observed to be a maximum for an Nd3+ substitution of 1 mol%. Upon poling, the PL intensity is observed to be quenched, consistent with the obtained XRD data, indicating an electric-field induced structural ordering towards higher symmetry, confirmed with the help of structural refinement. The evaluated ferroelectric to relaxor and antiferroelectric relaxor T(F–R) was observed clearly from the poled dielectric–loss curve for the 1 mol% of Nd3+ substitution. Furthermore, the optimized NBNT exhibited a lower Ec and a higher off-resonance figure of merit (FOMoff) for energy harvesting by 12% and 30%, respectively, in comparison with un-doped NBT.

We present a comprehensive investigation on the dependence of Nd3+ substitution on various properties in [ N a 0.5 B i 0.5 − x N d x ] T i O 3 (NBNT) for x = 0 − 0.1 . The structural analysis of XRD measurements revealed a crossover structural phase transition from monoclinic ( C c ) to orthorhombic ( P b n m ) for composition s 0.04 ≤ x ≤ 0.1 . Increase in Nd3+ substitution resulted in larger grain size. Enhanced electrical properties were observed for x = 0.01. Dielectric measurements revealed the relaxor behaviour enhances with the content of Nd3+, which is verified with help of bipolar strain loops. The polarization measurements support the evolution of centrosymmetry space group over particular cross over for NBNT with x = 0.04 . In concomitance with enhanced electrical properties, the luminescence measurements showed the largest emission for x = 0.01 for the Nd3+ substituted NBT. The onset of luminescence quenching starts from the substitution of x = 0.03 which can be surmised to be due to the effect of centro-symmetric ( P b n m ) of orthorhombic structure in addition to the expected concentration quenching effects. The results presented here, establishes the substitution of Nd3+ into the NBT resulted in enhanced electrical and optical properties compared to parent NBT, making these NBNTs promising candidate for multifunctionality applications.

The eco-friendly Na0.5Bi0.5TiO3 (NBT) and its derivatives have been synthesized by conventional solid state route. According to Judd-Ofelt theory, the higher symmetry phase suppresses the e...

Single-phase Er/Yb co-substituted 0.94(Na0.4K0.1Bi0.5−x–yErxYbyTiO3)–0.06(Ba0.85Ca0.15Zr0.1Ti0.9O3) $$(x = 0.01, \;y = 0.02\;{\text{and}}\; x = 0.02,\; y = 0.01)$$ (NKBT–BCZT) lead-free ceramics were synthesized by conventional solid-state reaction. The structural properties of the ceramics were confirmed with the help of X-ray diffraction studies. The crystal structure of NKBT–BCZT changed from rhombohedral to a morphotropic phase boundary and then to tetragonal phase in the presence of BCZT. The surface morphology of these ceramics was well packed with high-density and delineated grain boundaries which were confirmed with the help of the density of the samples. It was noted that the grain sizes decreased slightly by altering the Er/Yb compositions. The temperature dependence dielectric study revealed the existence of ferroelectric and antiferroelectric phase transformations in two independent regions. The temperature dependence conductivity study showed doubly ionized oxygen vacancies due to the presence of a defect dipole, which helps to promote ionic conductivity at a high temperature region. The observed room temperature P–E loops were identified from well-saturated slim loops having reduced coercivity which was found to be useful for potential applications in the field of energy storage devices.

Here with we reported a detailed synthesis of Fe/Cr co-doped Copper oxide nano particles with a simple and inexpensive wet chemical method. The pure and Fe, Cr substituted CuO nanoparticles was prepared with sol-gel chemical method are expedient for industrial application. The preliminary X – ray diffraction and Rietveld refinement study revealed a pure crystallinity nature with monoclinic crystal with C2/c phase. The average crystallite size was calculated by Scherrer’s formula in order of 21 nm and further observation indicates with increase concentration crystalline size increases. The scanning electron microscopy (SEM) images indicate particles are in 20-30 nm range. The Raman spectroscopic study indicates the existence of molecular groups in the CuO nanoparticles with the doping of Cr and Fe.

Herein, we present comprehensive investigations of the optical and electrical properties of Nd

BiFeO 3 (BFO) is well known room temperature multiferroic among all perovskite kind multiferroics. It shows very high ferroelectric Curie temperature T C = 1103 K and Neel temperature T N = 643 K [1]. The coupling between spin and charge in it would have an additional degree of freedom of changing magnetization by electric field and vice versa. However, the presence of oxygen vacancies and Fe 2+ /Fe 3+ ions lead to the leakage current which limits the potential of BFO in device applications [2]. It has been found that substitution of elements at A - site and/or B - site is quite effective to tackle these issues and to improve the physical properties. It is reported that A - site substitution by rare earth is quite effective in tuning the properties of BFO [2]. In a ddition to this, substitution of Sc at B - site reduces the leakage current and improves the insulating character of BFO [3]. It can be anticipated that co - substitution of Sm at A - site and Sc at B - site would improve the insulating character by reducing the l eakage currents and enhances the physical properties of BFO. In this work, polycrystalline BFO and Bi 0.85 Sm 0.15 Fe 0.90 Sc 0.10 O 3 (BSFSO) compounds were synthesized and their structural, dielectric and electrical properties were analyzed.

Recent studies on (0.96)Na0.5Bi0.5TiO3–(0.04)BaTiO3 (NBT-4BT)solid solution reveal the existence of the structural distortion of lower symmetric Cc phase rather than the R3c phase through high resolution X-ray diffraction and neutron diffraction. The Nd-modified NBT-4BT can be thought of a possible candidate for switchable optical properties and has been chosen for present studies. The structural distortion in this solid solution is found to be mixture of two structural phases. The coexistence of Cc along with minor phase reflections of P4mm was confirmed through structural refinement The systematic study of structural, electrical and optical properties on this solid solution has been performed.

Eco friendly (Na0.5Bi0.48Eu0.02) Ti1-xNbxO3 ceramics were synthesized with help of conventional solid state reaction by using high energy ball milling. The room temperature XRD of Nb5+ substituted NBET ceramics were stabilized in single phase pervoskite structure without any secondary phase. Polarization study reflects long range ferroelectric order for pure NBET ceramics and coercive field enhance with the substitution of Nb5+ ion at Ti site. Further, the substitution of Nb5+ ≥ 0.02 composition induced relaxor future. The energy density calculation shows the maximum energy storage density of 1.02 J/cm3 for x=0.02 ceramics. These results confirms a small fraction of Nb5+ doped NBET ceramics should be good candidates for energy storage applications.Eco friendly (Na0.5Bi0.48Eu0.02) Ti1-xNbxO3 ceramics were synthesized with help of conventional solid state reaction by using high energy ball milling. The room temperature XRD of Nb5+ substituted NBET ceramics were stabilized in single phase pervoskite structure without any secondary phase. Polarization study reflects long range ferroelectric order for pure NBET ceramics and coercive field enhance with the substitution of Nb5+ ion at Ti site. Further, the substitution of Nb5+ ≥ 0.02 composition induced relaxor future. The energy density calculation shows the maximum energy storage density of 1.02 J/cm3 for x=0.02 ceramics. These results confirms a small fraction of Nb5+ doped NBET ceramics should be good candidates for energy storage applications.

Nanocrystalline Pr3+ substituted NBT was synthesized using hydrothermal technique. Pr3+ modifies the ferroelectric NBT optically active and enhances the electrical properties with small structural changes. Aiming to the development of the bottom up optoelectronic devices this optimized nanoscale Na0.5Bi0.5-xPrxTiO3(x = 0.005) compound is synthesized hydrothermally. X-ray diffraction pattern shows that the system is stabilized in the Rhombohedral (space groupR3c) phase indicating the local strain inhomogeneity. PE loop shows that there is a decrement in the Ec value compared with compounds synthesized using conventional methods. The strong red emission assigned to prominent transition of the Pr3+ ions at 610nm was observed along with weak blue-green emission, indicating the potential use of the system. Energy transfer from host system to Pr3+ ions is responsible for red emission while blue green emission is due to quenching of 3P0 induced by intervalence charge transfer state.

BiFeO3 (BFO) and Bi0.85Sm0.15Fe0.90Sc0.10O3 (BSFSO) ceramics were synthesized by conventional solid state route. X-ray diffraction measurements revealed that an orthorhombic Pnma structure evolved with a phase fraction of 84% in the rhombohedral R3c structure of BFO upon the substitution of Sm and Sc. The changes in the intensity and the frequency of Raman modes also corroborated the structural transformation in the BSFSO compound. A decrease in grain size, reduction in porosity, and improved density were observed in the BSFSO compound. An enhanced remanent magnetization of 0.2 emu/g and coercive field of 6.2 kOe were observed, which were attributed to the structural change as well as the destruction of the spin structure with the substitution. Impedance and leakage current measurements revealed that the insulating character of BFO was improved with the substitution of Sm and Sc in BFO and was explained based on the bond enthalpy concept. The enhanced magnetic properties along with the improved insulating character of BSFSO compound will be suitable for device applications.

Eco-friendly 0.92(Na0.5Bi0.49Nd0.01TiO3)-0.08(BaTiO3) [denoted as NBNT-BT 92/8] ceramic is synthesized with the help of conventional solid state reaction route. The structural phase pure studies reveals, the compound stabilizes into mixed phase of Cc + P4 mm and the surface morphology of microstructure shows the uniform distribution of Nd. The temperature dependent dielectric study reveals two typical anomalies with the diffuse phase transition and show the relaxor future estimated with the help of diffusivity (γ). From the temperature dependent polarization and room temperature bipolar strain hysteresis loops over broad electrical field range from (0–73) kV cm−1, the estimated energy storage density, energy storage efficiency, and strain values are Wrec ≈ 1.53J cm−3, η ≈ 93(%), and S(%) ≈ 0.4, respectively, which is the best obtained value among available various reported lead-free piezoelectric ceramics. The adiabatic or electrocaloric temperature change (ΔT) is calculated to be ΔT ≈ 0.95 K at 50 kV cm−1. The obtained valued of ΔT, strain and energy storage density for NBNT-BT 92/8 is tremendous enhancement compared with absence of Nd in NBT-BT 92/8.

In this work, we report the simultaneous optimization of the relaxor properties and photoluminescence from nanocrystalline Nd3+ substituted NBT (Na0.5Bi0.5-xNdxTiO3 where x = 0,0.01,0.02 and 0.04) synthesized by hydrothermal method. Substitution of optically active Nd3+ results in luminescence in addition to modification of structural and electrical properties of parent NBT. NBT-Nd ceramics stabilize in rhombohedral structure which is confirmed from X-ray diffraction analysis. Here, the long range structure is associated with the removal of local strain inhomogeneity by hydrothermal synthesis. The variation of morphology observed from the transmission electron micrographs is conjectured as the result of the nucleation process involved with Nd3+ content in hydrothermal process. The Raman spectral measurements concur with the observed rhombohedral symmetry. Upon photo-excitation typical NIR emission from Nd3+ in the NIR region is observed. The variation in the dielectric and the optical properties are correlated well with the structural observations for NBT-Nd compositions.

We have designed a promising optofluidic laser device based on a microfluidic structured channel filled with an ethanolic dye solution. We report random laser emission attributed to the inherent randomness of the structure. The systematic study of the emission dependence on various pump laser parameters reveals fundamental aspects as well as potential applications of this system.

ZnO and Zn2SiO4 nanoparticles embedded SiO2 waveguides, a new candidate for fabrication of low-loss glass-ceramic active-waveguides for integrated optic applications, were fabricated by the sol-gel technique using dip-coating process. The waveguides fabricated from the sol-gel solution composed of (100-x) SiO2–x ZnO (x = 25, 30, and 35 mol %) exhibited uniform thickness (1.5 ± 0.1 µm), and refractive index of 1.529 ± 0.005 (for x = 35 mol %) at 632.8 nm. Propagation loss of 1.4 ± 0.2 dB/cm at 632.8 nm was observed in the transparent glass-ceramic waveguides. The as-prepared waveguides contained nanoparticles of average size ~15 nm uniformly dispersed in the SiO2 matrix. Formation of Zn2SiO4 along with ZnO nanoparticles in the waveguides is confirmed from the X-ray diffraction patterns and photoluminescence spectra. The tuning of the optical and spectroscopic properties by controlled heat-treatment of the as-prepared active-waveguides has been demonstrated.