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The goal of this research is to create a perovskite ceramic with electrical and dielectric properties appropriate for energy storage, medical uses, and electronic devices. A bismuth ferric titanate, Bi0.7Ba0.3(FeTi)0.5O3, doped with barium and crystalline, was effectively synthesized at the A-site via sol–gel synthesis. A rhombohedral structure emerged in the R3́C space group, which was confirmed by room-temperature X-ray studies. An average grain size of 263 nm and a homogeneous grain distribution and chemical composition were confirmed by the results of scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The study established a clear relationship between temperature, frequency, and the electrical properties of the material. Impedance spectroscopy and electrical modulus measurements, performed in the frequency range of 1 kHz to 1 MHz and at temperatures ranging from 200 K to 360 K, demonstrated a non-Debye type of relaxation. Furthermore, once the material was produced at various temperatures, its frequency-dependent electrical conductivity was examined using Jonscher's law. The results demonstrate that barium doping significantly improves the electrical conductivity and dielectric properties compared to pure BiFeTiO₃. Over the complete temperature range, consistent conduction and relaxation mechanisms were discovered. These findings suggest that the chemical may find widespread applicability across a broad temperature range, including electrical fields and capacitors. Highlights: Successful Synthesis: A perovskite ceramic, Bi0.7Ba0.3(FeTi)0.5O3, was synthesized using the sol–gel method, doped with barium at the A-site. Structural Properties: X-ray diffraction confirmed a rhombohedral structure in the R3́C space group, with an average grain size of 263 nm, as analyzed through SEM and EDX techniques. Enhanced Electrical and Dielectric Properties: Barium doping significantly improved the electrical conductivity and dielectric properties of the material compared to undoped BiFeTiO₃, making it suitable for energy storage and electronic applications. Non-Debye Relaxation Behavior: Impedance spectroscopy and electrical modulus analysis in the frequency range of 1 kHz to 1 MHz and temperature range of 200–360 K revealed non-Debye type relaxation. Wide Applicability: The study identified stable conduction and relaxation mechanisms over a broad temperature range, suggesting potential use in capacitors and electrical fields across various temperature conditions. [ABSTRACT FROM AUTHOR]

Cobalt ferrite (CoFe2O4) ceramics were effectively synthesized using the co-precipitation method, followed by an investigation into the impact of sintering temperature on various properties including structure, morphology, magnetism, and dielectric behavior. These obtained ceramics exhibited a spinel ferrite structure with cubic symmetry. The average grain size increased from 0.26 to 0.83 μm, as the sintering temperature raised from 400 to 1000 °C. Dielectric measurements demonstrated significant temperature-dependent behavior across all frequencies, suggesting a pronounced influence on polarization within the ferrites, likely caused by localized electron displacement due to electronic exchange between Fe2+ and Fe3+ ions along the direction of the applied electric field. Analysis of impedance and modulus confirmed a negative temperature coefficient of resistance (NTCR) response. Additionally, the increase in ac conductivity with temperature was found to enhance charge hopping, resulting in decreased activation energy (Ea) for specimen mobility responsible for conduction. Magnetic properties exhibited enhancement with increasing sintering temperature, with maximum magnetization, coercivity, and remanent magnetization values increasing accordingly. However, non-saturation at high fields suggested surface effects in the CoFe2O4 ceramics. Notably, the CFO ceramic sintered at 1000 °C displayed a maximum magnetization value of approximately 74.54 emu/g at room temperature, while the highest coercivity value among all samples was 1368.33 Oe for the sample sintered at 900 °C. [ABSTRACT FROM AUTHOR]

The ceramic Sr(NiNb)0.5O3, incorporating silver doping in the A site, was synthesized using a sol–gel route and subjected to comprehensive analysis through various experimental techniques. X-ray diffraction data analysis indicates a rhombohedral crystal structure. Scanning electron microscopy (SEM) examination reveals densely packed grains with minimal surface porosity. A thorough investigation of electrical properties, encompassing dielectric constant, loss tangent, electrical impedance, modulus, conductivity, etc., was conducted across a wide frequency range (103–106 Hz) and temperature range (260–340 K). This analysis provided valuable insights into structure–property relationships and conduction mechanisms. The discussion highlights the significance of interface effects, space charge polarization, and Maxwell–Wagner dielectric relaxation in achieving the material's high dielectric constant at low frequencies and elevated temperatures. Examination of temperature dependence through Nyquist plots elucidates the contributions of grain behavior to the material's resistive and capacitive properties. The dielectric permittivity, dissipation of energy, and electrical characteristics like impedance, modulus and conductivity are notably influenced by the frequency of the applied electric field and temperature. Overall, the material exhibits promising potential for industrial applications such as energy storage, given its intriguing properties. [ABSTRACT FROM AUTHOR]

This paper discusses the structural, microstructure and electrical properties of perovskite oxide lanthanum nickel LaNiO3, synthesized by the sol–gel reaction technique that was investigated. The prepared material was doped with bismuth and niobium and studied their properties. The Rietveld refinement of the X-ray diffraction pattern suggests that the compound has a monoclinic phase at room temperature with a P21/n space group. Scanning electron microscopy surface morphology analysis of the sample showed closed packing of grains with good density and very little porosity. The frequency-dependent modulus of the material is investigated in the temperature range from 200 K to 360 K and in range frequency between 1 kHz and 1 MHz. The Cole–Cole model is used to analyze the dielectric relaxation phenomenon. The complex impedance data are analyzed by an electrical equivalent circuit consisting of a resistance and a constant phase element, where the ideal capacitance part is replaced by a constant phase element. The frequency-dependent conductivity spectra follow the Jonscher power law. Nevertheless, the Arrhenius-type conduction mechanism was found to be active in the sample with activation energy of 0.168 eV. The electrical property of the sample was found to be independent of temperatures, making it a potential candidate for thermally stable capacitor application. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive investigation into the structural, morphological, and electrical properties of sol-gel synthesized Ba0.75Ni0.25Tc0.88Mn0.12O3 perovskite ceramic (BNTMO). The meticulous preparation protocol, involving solvating various precursors, was followed by an extensive characterization employing X-ray diffraction, scanning electron microscopy, and dielectric studies. XRD analysis affirmed the single-phase single-phase cubic structure with Pm-3m space, while SEM revealed a well-defined morphology with an average particle size of 243 nm. The electrical conductivity exploration, elucidated through Jonscher's universal power law, provided insights into charge carrier dynamics, exhibiting semiconductor behavior. Impedance spectroscopy unraveled a distinctive relaxation peak, corroborated by Cole-Cole plots, unveiling a unique charge carrier mechanism. Dielectric studies showcased intriguing polarization dynamics, indicating promising applications in energy storage. The convergence of activation energy values from various analyses underscores the coherence in the charge carrier relaxation process. Overall, our findings contribute to a nuanced understanding of the electrical intricacies of BNTMO, presenting avenues for its utilization in advanced technological applications. Highlight: X-ray diffraction (XRD) confirmed that Ba0.75Ni0.25Tc0.88Mn0.12O3 (BNTMO) has a cubic structure (Pm-3m). Scanning electron microscopy (SEM) showed BNTMO has a well-defined morphology with 243 nm average particle size. BNTMO exhibited semiconductor behavior, with electrical conductivity following Jonscher's universal power law. Impedance spectroscopy showed a relaxation peak and Cole-Cole plots indicated a unique charge carrier mechanism. Dielectric studies suggested potential energy storage applications with consistent activation energy values. [ABSTRACT FROM AUTHOR]

This study undertakes a comparative analysis of the structural, morphological, electrical, and magnetic characteristics of Fe-doped LaMnO 3 ceramics. The solid-state reaction method was used to prepare Fe-doped LaMnO 3 at different concentrations (0.00 ≤ x ≤ 1.00) and has been characterized using X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), Field emission scanning electron microscopy (FE-SEM), energy-dispersive spectroscopy (EDS), and vibrating sample magnetometry (VSM). The structural transformation from rhombohedral to orthorhombic with Fe-doping is demonstrated by Rietveld's refined XRD patterns. The positive slope in Williamsons-Hall's (W-H) plots confirms the presence of tensile strain with increasing average crystallite size. Quasi-spherical morphology of all the compositions with similar uniformity was confirmed by FESEM images. The chemical distribution of all the elements has been identified by EDS mapping images. Normal dielectric dispersion behaviour of all the samples with NTCR response is confirmed by dielectric and impedance analysis respectively. Increasing lattice volume with Fe-concentration results is increasing E a . The presence of antiferromagnetic ordering, in addition to weak ferromagnetic ordering, is indicated by the unsaturated magnetization even up to a high external field. The decrease in M S and increase in H C values due to Fe-doping reflect the influence of particle size on various magnetic parameters., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)

This manuscript investigates the structural and electrical properties of a Ba 0.75 Bi 0.25 Ni 0.7 Mn 0.3 O 3 (BNMO) perovskite compound synthesized through the sol-gel method. The orthorhombic crystal structure of the sample is confirmed by X-ray diffraction analysis. The electrical conductivity of BNMO is found to increase with frequency, indicating the presence of local charge carriers. The AC electrical conductivity follows Jonscher's equation, exhibiting a plateau at low frequencies and a power-law behavior at high frequencies. The activation energy for conduction is determined to be 0.654 eV. Impedance spectroscopy reveals the presence of grain and grain boundary contributions, which are modeled using an R -CPE combination circuit. Analysis of the electrical modulus demonstrates non-Debye type relaxation and indicates the presence of charge carrier hopping between Mn 2+ and Mn 3+ ions. The activation energy obtained from the relaxation peaks of the modulus is found to be 0.674 eV. The dielectric constant exhibits high values that increase with temperature. This observation suggests that the capacitance behavior holds promising potential for energy storage applications, making it a suitable candidate for various technological uses., Competing Interests: The authors affirm that they did not accept any money, grants, or other assistance for the creation of this manuscript., (This journal is © The Royal Society of Chemistry.)