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Ferrites are among the most frequently investigated materials mainly due to interesting and practically different properties. Therefore, easily and cost-effective lanthanum doped Mg 0.5 Cd 0.25 Cu 0.25 Fe 2-x La x O 4 (x = 0.0, 0.0125, 0.025, 0.0375 and 0.05) ferrites were synthesized by a co-precipitation route, a comprehensive characterisation of their structural, optical, electric, dielectric, molecular vibrational, and magnetic properties were carried out. X-ray diffraction analysis confirmed the formation of a cubic spinel structure. Variations in frequency bands were also observed with amplification in optical band gap energy (2.95 – 3.38 eV) due to La3+ ions insertion. The electric resistivity had opposite trends at low and high temperatures with increasing La3+ content. The Curie temperature, activation energy, and drift mobility were also determined to have values consistent with the semiconducting behavior of the soft ferrites. The saturation magnetization (M S) has a maximum value 49.385 emu/g with remanent magnetization (M r) was 34.928 emu/g and coercivity 661.4 Oe for La3+ concentration x = 0.05. The minimum dielectric loss was observed for La3+ concentration x = 0.025. Moreover, the resistivity (ρ) has a maximum value of 7.95 × 104 Ω cm for La3+ concentration x = 0.025. The calculated frequency range of La3+ doped Mg–Cd–Cu ferrites was detected in the microwave range (3.36 – 10.80 GHz), suggesting the potential application of the materials in longitudinal recording media and microwave absorbance. [Display omitted] • La3+ doped Mg–Cd–Cu ferritessamples synthesized via co-precipitation. • The lattice constant increased with La3+ substitution. • At 303 K, for La3+ concentration x = 0.025, maximum resistivity was observed. • Magnetization saturation was increased with La3+ concentration. [ABSTRACT FROM AUTHOR]

Liver cancer or hepatocellular carcinoma (HCC) is leading cause of cancer-related mortalities globally. The therapeutic approaches for chronic liver diseases-associated liver cancers aimed at modulating immune check-points and peroxisome proliferator-activated receptor gamma (PPARγ) signaling pathway during multistep process of hepatocarcinogenesis that played a dispensable role in immunopathogenesis and outcomes of disease. Herein, the review highlights PPARγ-induced effects in balancing inflammatory (tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, IL-1) and anti-inflammatory cytokines (IL-10, transforming growth factor beta (TGF-β), and interplay of PPARγ, hepatic stellate cells and fibrogenic niche in cell-intrinsic and –extrinsic crosstalk of hepatocarcinogenesis. PPARγ-mediated effects in pre-malignant microenvironment promote growth arrest, cell senescence and cell clearance in liver cancer pathophysiology. Furthermore, PPARγ-immune cell axis of liver microenvironment exhibits an immunomodulation strategy of resident immune cells of the liver (macrophages, natural killer cells, and dendritic cells) in concomitance with current clinical guidelines of the European Association for Study of Liver Diseases (EASL) for several liver diseases. Thus, mechanistic insights of PPARγ-associated high value targets and canonical signaling suggest PPARγ as a possible therapeutic target in reprogramming of hepatocarcinogenesis to decrease burden of liver cancers, worldwide. Mechanistic insights of PPARγ-associated high value targets and canonical signaling for cellular reprogramming of hepatocarcinogenesis. [Display omitted] [ABSTRACT FROM AUTHOR]

Y-type hexaferrite ceramic materials of nominal composition Ba 2 Co 2 Cr x Y x Fe 12-2x O 22 (x = 0.00, 0.03, 0.06, 0.09, and 0.12) were synthesized by sol-gel auto combustion route. Y-type hexaferrites are technologically important ceramic materials for fabricating modern electronic devices and microwave absorbers due to their unique electrical and dielectric properties and reflection loss behavior. XRD classifies the single-phase formations with space group R 3 ‾ m. The crystallite size of the synthesized samples was calculated in (34–41) nm range. The specific absorption band in FTIR spectra approves the (Fe–O) stretching vibrations at wavenumbers 446 and 478 cm−1. The substitution of iron by Cr3+ and Y3+ increases DC resistivity from 1.03 × 1011 to 1.17 × 1012 Ω cm by limiting the electrons jumping between ferrous and ferric ions. The activation energy and drift mobility were also calculated among the substituting content of Cr3+-Y3+. The dielectric response in 1 MHz–6 GHz frequency was determined and the effect of substitution has been observed. The Maxwell-Wagner (MW) bilayer model is used to study dispersion in dielectric parameters with reference to applied frequency. The maximum values of dielectric losses were obtained at 6 GHz in the range of 0.37–0.60. The coercivity values confirms the soft magnetic nature of synthesized samples. The microwave absorption (MW) properties of synthesized materials were improved upon Cr3+-Y3+ substitution. Minimum reflection loss R Lmin = −66 dB (99.99% absorption of MW) at 1.46 GHz frequency and 1.96 mm thickness was obtained for x = 0.09 composition. All investigated samples are efficient materials for stealth technology, radar cross-reduction, EM interference shielding, and high-frequency applications. [ABSTRACT FROM AUTHOR]

Rare earth cerium (Ce3+) doped Cu 0. 5 Cd 0. 25 Co 0.25 Ce x Fe 2-x O 4 (x = 0, 0.0125, 0.025, 0.0375, 0.05) spinel ferrites nanoparticles were synthesized via co-precipitation technique. XRD, FT-IR, UV-VIS, VSM, LCR and current-voltage measurement techniques were utilized to investigate the structural parameters, metal stretching vibrations, indirect energy band gap, magnetic parameters and electrical behavior of synthesized ferrite powders respectively. The XRD patterns confirmed the remarkable reduction in crystallites size, cell volume and lattice constant while both densities (ρ x , ρ b u l k ) tends to increase with rise in Ce3+contents(x). The indirect energy band gaps (E g) and the DC electrical resistivities were found in decreasing order from 3.48 to 2.50 eV and 9.902 × 107 to 0.142 × 107(ohm-cm) respectively at room temperature (303 K) with Ce3+ doping concentration. LCR meter inveterate that the dielectric constant had declining, and ac conductivity had growing trend at fix value of cerium concentration with rise of frequency from 8 Hz to 8 MHz. The soft magnetic properties can be significantly improved by the small amount of Ce3+ ion doping (x = 0.0375) with an increase of the saturation magnetization (Ms), and retentivity (Mr). [ABSTRACT FROM AUTHOR]

Due to their outstanding properties, low cost, and environmental friendliness, mixed transition metal oxides are frequently used in various applications. In this study, Ce3+ doped CdFe 2 O 4 powder samples were prepared through the co-precipitation process. A peak shift was observed towards a lower 2 θ angle with the substitution of Ce3+ at their lattice site and the lattice constant has a maximum value for the x = 0.06 sample with the crystallite size of 34 nm. Moreover, for x = 0.06 sample, the resistivity was found in the order of 106 Ω cm and the dielectric tangent loss had a smaller value. The electrical and dielectric analysis of the as-prepared x = 0.06 sample indicate that it is the best for high-frequency applications. • The Ce3+ doped CdFe 2 O 4 samples were prepared via the co-precipitation route. • The crystallite size was found 34 nm for a sample having Ce3+ x = 0.06 sample. • The x = 0.06 sample resistivity was observed in the order of 106 Ω cm. • The dielectric tangent loss has a smaller value for the x = 0.06 sample. • The electrical and dielectric properties suggested that x = 0.06 sample is suitable for high-frequency applications. [ABSTRACT FROM AUTHOR]

Transition metal vanadate nanostructures are getting significant importance as an efficient electrode material for modern energy storage applications. In this work, a simple hydrothermal method is employed for the synthesis of magnesium vanadate (MgV 2 O 5) and Ag-doped magnesium vanadate (Ag doped MgV 3 O 8) nanomaterials. The X-ray diffraction (XRD) analysis reveals the formation of an orthorhombic structure for magnesium vanadate, whereas the Ag-doped magnesium vanadate results in a monoclinic structure. Interestingly, the optical bandgap is observed to increase from 2.85 eV to 3.92 eV with the increase in Ag-doping as revealed from Tauc's plot of the UV-visible absorption spectrum. The electrochemical performance of magnesium vanadate electrodes is thoroughly investigated by cyclic voltammetry (CV), Galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy. The Ag-doped magnesium vanadate shows higher specific capacitance (C s = 706 Fg−1) in comparison to undoped (325 Fg−1) at a current density J = 5 Ag−1. The theoretical investigations through Dunn's model demonstrate a major contribution arises from surface-controlled processes, which increase as high as 91% at scan rate of 60 mVsec−1. Our findings indicate that Ag-doping significantly improves the overall electrochemical response of magnesium vanadate as an efficient electrode material for supercapacitor applications. [Display omitted] • Phase and lattice parameters of zinc vanadate are changed due to difference in ionic radii of dopant element (Ag). • Variable oxidation of states of vanadium are observed which cause improvement in electrochemical response. • Ag (2%) doped magnesium vanadate shows higher specific capacitance (Cs = 706 Fg−1) than undoped (325 Fg−1). • Silver-modified electrode exhibits energy density and power density of 65.5 Whkg−1 and 12,100 Wkg−1 respectively. [ABSTRACT FROM AUTHOR]

The impact of Cr3+ substitution on the electrical and dielectric properties of Y-type hexaferrites with composition Ba 2 Mg 2 Cr x Fe 12-x O 22 (x = 0.0, 0.5, 1.0, 1.5, and 2.0) was synthesized by the sol-gel auto combustion technique. The lattice parameters 'a' and 'c' slightly increase with the substitution content of Cr3+, and some other physical parameters, including porosity, microstrain, dislocation density, specific surface area, and stacking fault coefficient, were determined from XRD data. FTIR spectra confirm the formation of iron oxide base material by the appearance of three signature bands at precisely 429, 474, and 499 cm-1 due to Fe–O vibrations at octahedral and tetrahedral sites. Substituting Cr3+ at the octahedral site enhanced the room temperature DC electrical resistivity from 6.89 × 109 to 2.27 × 1010 Ω-cm. Temperature-dependent DC electrical resistivity exhibits semiconducting behavior. There is a direct relation between resistivity and activation energy. The dielectric behavior of Cr3+ substituted samples in the frequency range of 1 MHz–6 GHz was understood based on the conduction mechanism through the hopping of electrons between Fe3+ and Fe2+ ions and the Maxwell-Wagner Model. In impedance spectroscopy studied using Cole-Cole plots, most dielectric response arises from the contribution of the grain boundary effect. With the substitution of Cr3+, dielectric losses decreased. A very high Q-value around 1 GHz was observed, suggesting that these hexaferrites are efficient materials for many high-frequency applications, such as multi-layer chip inductors (MLCI), dielectric resonators, and power applications. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this review was to examine the comprehensively accumulated data regarding potential therapeutic aspects of exogenous administration of interleukin 33 (IL-33) or its antagonists in allergic, cancerous, infectious, and inflammatory diseases. Methods A selected review was undertaken of publications that examined the protective and exacerbating effects of IL-33 or its inhibitors in different diseases. Mechanisms of action are summarized to examine the putative role of IL-33 in various diseases. Findings IL-33 promoted antibacterial, antiviral, anti-inflammatory, and vaccine adjuvant functions. However, in T H 2-biased respiratory, allergic, parasitic, and inflammatory conditions, IL-33 exhibited disease-sensitizing effects. The alarmin cytokine IL-33 induced protective effects in diseases via recruitment of regulatory T cells; antiviral CD8 + cells, natural killer cells, γδ T cells, and nuocytes; antibacterial and antifungal neutrophils or macrophages; vaccine-associated B/T cells; and inhibition of nuclear factor–κB–mediated gene transcription. In contrast, IL-33 exacerbated the disease process by increasing T H 2 cytokines, IgE and eosinophilic immune responses, and inhibition of leukocyte recruitment in various diseases. Implications The protective or exacerbated aspects of use of IL-33 or its inhibitors are dependent on the type of infection or inflammatory condition, duration of disease (acute or chronic), organ involved, cytokine microenvironment, dose or kinetics of IL-33, and genetic predisposition. The alarmin cytokine IL-33 acts at cellular, molecular, and transcriptional levels to mediate pluripotent functions in various diseases and has potential therapeutic value to mitigate the disease process. [ABSTRACT FROM AUTHOR]

Technology important ferrites ceramic Sr 2 Ni 2 Ga x Fe 12-x O 22 (x = 0.00, 0.2, 0.4, 0.6, and 0.8) samples were produced using sol-gel auto combustion route. Structural, electrical, dielectric, and magnetic parameters were identified by substituting Ga3+ at the Fe3+ site. It was recognized that an increase of Ga3+ content in (Sr 2 Ni 2 Ga x Fe 12-x O 22) ceramic samples first decreased, then increased lattice parameters, and the density of samples was observed. This is because of the ionic radii and atomic weight of Ga3+ and Fe3+ cations. FTIR spectra show two characteristic absorption bands at 444-513 cm−1 caused by metal-oxygen vibrations. Due to the contribution of smaller grains of samples, the higher values of resistivity were observed, which vary from 3.78 × 1010 (Ω cm) to 1.13 × 1011 (Ω cm) by the substitution of Ga3+ ions at the octahedral site. The activation energy was measured between 0.20 and 0.61 eV. The dielectric response of Ga3+ substituted ferrite ceramic samples were studied in the 1 MHz-6 GHz frequency region. The Maxwell-Wagner bilayer model studied the effect of polarization with applied frequency on dielectric parameters. With the substitution of Ga3+, minimal losses in the range 0.34–0.44, about 6 GHz, and a high Q-value of about 10,000 were observed for each sample. In impedance spectroscopy analysis Cole-Cole plots confirm that the dielectric response is because of the influence of grain boundaries. The substitution of Ga3+ enhances saturation magnetization (68.20–71.78 emu/g) while coercivity decreases (655.86–507.86 Oe). In the present finding, the low dielectric loss, moderate permittivity, high value of the Quality factor, and very high value of resistivity of about 1.13 × 1011 that reduces the eddy current losses suggested that these materials are appropriate candidates for many high-frequency applications such as multilayer chip inductor, dielectric resonators, power applications, and microwave devices. [ABSTRACT FROM AUTHOR]

A series of (Zr–Co) substituted Y-type polycrystalline hexaferrite with composition SrBaNi 2 (ZrCo) x Fe 12-2x O 22 (x = 0.0, 0.25, 0.50, 0.75, 1.0) were fabricated by sol-gel auto combustion method. Pure Y-type single phase formation was achieved at a relatively lower temperature of 1150 °C for 5:30 h. The fabricated nano ferrites were examined by X-ray powder diffraction to confirm the pure single-phase formation of Y-type hexaferrites. An increase in lattice parameters (a& c) was observed by adding Zr4+-Co2+ metal cations. Crystallite size (D) measured in the 48-19 nm range. FTIR spectra clarified iron-oxygen vibrational bands at 417-487 cm−1, which approved the Y-type hexaferrites formation. DC electrical resistivity has an opposite trend at high and low temperatures with increasing Zr4+-Co2+ content (x). DC electrical resistivity values depend on grain size; they have an inverse relation. Activation energy, drift mobility, and Curie temperature were also determined. Conduction is due to the hopping of electrons below the Curie temperature, and polarons are responsible for hopping above the Curie temperature. Activation energy varies from 0.39 to 0.10 eV with the substitution of Zr4+-Co2+ ions. A wide frequency range of dielectric characteristics (1 MHz–6GHz) was observed, and these parameters revealed a considerable fluctuation with the substitution of Zr4+–Co2+ ions. Dielectric constant, dielectric loss and ac conductivity of nano ferrites materials increased with frequency and Zr4+-Co2+ content (x). Complex impedance spectroscopy formalism using the Cole-Cole plots indicated that most dielectric responses arise from grain boundary contributions. [ABSTRACT FROM AUTHOR]

Lanthanum (La3+) substituted Mg-Cd-Bi ferrite nanoparticles were synthesized by sol-gel auto combustion route consuming high quality nitrates. The impact of lanthanum concentration on microstructural and electrical properties in the ferrite series Mg 0.5 Cd 0.5 Fe 1.95 Bi 0.5-x La x O 4 (x = 0.0, 0.01, 0.02, 0.03, 0.04, 0.05) was investigated. The samples were characterized by X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FTIR), scanning electron microscope (SEM), and Current-voltage (I-V) analyzerfor compositional, structural, morphological and electrical analysis. Upon varying the lanthanum content, it is observed that all the samples retained perovskite BiFeO 3 phase with distorted rhombohederal structure. Furthermore, it is revealed that the sintering process can significantly control the structural defects and crystal imperfections which affect the electric and magnetic nature of ferrites. The conduction process in La3+-dopedferrite series is originated by the hopping of electrons between ions of same elementswhich reduced the electrical resistivity and depicts the semiconductor nature of synthesized samples.Thus, it is believed that the optimal doping of lanthanum content in La3+-substituted Mg-Cd-Bi ferrites followed by post-annealing can remarkably tune the electrical properties of synthesized ferrite nano particles. [ABSTRACT FROM AUTHOR]

The impact of holmium (Ho) ions on lithium-rich spinel ferrites is studied through magnetic, morphological, and electrical transport properties. The X-ray photoelectron spectroscopy (XPS) analysis indicated the existence of all metal ions in the required valence state. Transmission electron microscopy (TEM) analysis exhibited nano-crystalline (∼50 nm) structures of these ferrites. The electrical resistivity measurements showed the higher resistivity values of the synthesized samples. The resistivity increased from 2.4 × 108 to 2.1 × 1010 Ω-cm with Ho inclusion, indicated an inverse relation with the size of grains. The Curie temperature (T c ) observed to decrease from 848 to 806 K with the incorporation of Ho 3+ ions. The activation energy (Δ E a ) noted to vary between 0.21 and 0.23 eV. The drift mobility (μ d) study revealed a decrease from 1.86x10 −12 to 6.14x10 −14 cm 2 V −1 s −1 by increasing Ho amount up to x = 0.06. A reduction in thermoelectric power (S) from - 143 to -95 μ.V/K by increase in Ho concentration confirmed the Fe replacement by Ho on octahedral B-sites. The ferromagnetic resonance (FMR) investigations indicated a drop in FMR line-broadening (ΔH) from 2491 to 2000 Oe by the increase of Ho concentration, making it beneficial to reduce microwave losses. A non-linear variation in the resonance field (H res) with the substitution of Ho was observed between 7359 to 7785 Oe. [ABSTRACT FROM AUTHOR]

We investigate here the effect of holmium on Li–Co nano-ferrites to elaborate the surface morphology, dynamic magnetic and electrical transport properties. The transmission electron microscopy (TEM) technique was employed to examine the microstructure and grain size distribution. TEM analysis confirmed the nanocrystalline nature (~50 nm) of the prepared materials. X-ray photoelectron spectroscopy (XPS) experiment results verify the presence of all metal ions with the required valences. Ferromagnetic resonance (FMR) analysis revealed the need for a dense microstructure to cut down the microwave losses. FMR line width was observed to reduce from 2757 -to 1676 Oe except for x = 0.12 by the substitution of Ho ions which correspond to low microwave losses. The dc resistivity results show that high resistivity values are associated with smaller grains of the samples and vice versa. Resistivity values are found to increase from 3.66 × 108 -to 5.31 × 108 Ω-cm by increasing the Ho addition. Seebeck experiment revealed n-type conduction. Together with showing the nature of charge carriers, a decrease in the Seebeck coefficient with increasing Ho ensured the replacement of Fe ions by Ho ions on B-sites. [ABSTRACT FROM AUTHOR]

Z n 0.5 C o 0.25 C u 0.25 F e 2 − x L a x O 4 (x = 0.0, 0.0125, 0.025, 0.0375, 0.05) ferrite powders with uniform distribution of ions and close-packed configuration were prepared via sol-gel auto-combustion route. XRD spectra showed the formation of spinel-phase cubic crystalline structure. SEM results revealed that the irregularity in size and shape of particles increases, and particle distribution uniformity decreases with La3+ concentration. Moreover, each curve of the UV–vis spectra revealed two optical energy band gaps. More importantly, DC resistivity (ρ) and the activation energy (Δ E) have minimum values at x = 0.0375. The dielectric loss was explained according to Maxwell-Wager space charge polarization. The P-E loop showed the ferroelectric nature of the synthesized samples. Moreover, VSM results revealed that the as-prepared samples possessed maximum saturation magnetization (M S = 56.77 ± 0.0283) and 8–12 GHz operating microwave frequency (ω m) range at x = 0.0375. All these results show the potential of Z n 0.5 C o 0.25 C u 0.25 F e 1.9625 L a 0.0375 O 4 ferrite powders for X-band microwave applications. Image 1 • Zn 0.5 Co 0.25 Cu 0.25 Fe 2-x La x O 4 ferrite powders via simple sol-gel auto-combustion. • Crystallite size and lattice constant decrease with increasing La3+ cations. • Optical band gap energies and DC resistivity have minimum values at x = 0.0375. • The ferroelectric nature of all the samples was confirmed using the P-E loop. • Maximum magnetization saturation was observed at x = 0.0375. [ABSTRACT FROM AUTHOR]

The yttrium substituted cadmium ferrites having composition Cd 1-x Y x Fe 2 O 4 (X = 0.00, 0.125, 0.250, 0.375, 0.500) were synthesized by the co-precipitation method and sintered at 1100 °C for 6 h. Structural, morphological, electrical, optical and dielectric characteristics were explored by XRD, SEM, EDS, FTIR, I–V two probes, UV–Vis and LCR techniques.XRD results confirmed the cubic structure of spinel ferrites. A decrease in lattice constants of the prepared samples was observed with the substitution of Y ions and was attributed to the difference in ionic radii of Y3+ (0.95 Å) and Cd2+ (0.97 Å) ions. Cationic distributions, ionic radii of both tetrahedral and octahedral sites, tolerance factor, oxygen positional parameters, bond lengths, interatomic distances, positional parameters and bond length angles were calculated from XRD data. The morphology of the prepared ferrites was studied using SEM and results ratified the XRD results. EDS confirmed the presence of all inserted elements in Cd 1-x Y x Fe 2 O 4 composition. DC resistivity and drift mobility of soft-ferrites were found to be increased from 1.047 × 108–4.822 × 1010 Ω-cm and 5.87 × 10−12 – 1.045 × 10−14 cm2V−1s−1, respectively, at 523 K with yttrium content confirming the behavior of semiconductor materials. The optical band gap energy calculated from the UV–Vis pattern of the Cd 1-x Y x Fe 2 O 4 system was decreased from 3.6011 to 2.8153 eV. DC resistivity and optical band gaps exposed inverse relation. FTIR results revealed lower and upper-frequency absorption bands in the ranges of 419.31–417.01 cm−1 and 540.95–565.70 cm−1, respectively. Dielectric constant and dielectric losses were in decreasing order, while ac conductivity revealed rising behavior with increasing frequency. Results showed the potential of yttrium doped Cd nanoferrites for applications in high-frequency microwave absorbing devices. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Establishment of time-dependent acetaminophen-induced oxidative stress. • Cinnamon aqueous extract possesses antioxidant potential. • Cinnamon pretreatment prevents acetaminophen-induced acute liver and kidney injury. Abstract Cinnamomum zeylanicum , a widely used spice and flavor, is used in the treatment and prevention of many diseases. In the current study, Balb/c mice were pretreated with cinnamon bark aqueous extract (200 mg/kg/day i.g.) 14 days prior to intragastrically administer single toxic dose of acetaminophen (200 mg/kg). Blood samples were collected for analysis of biochemical and oxidative stress parameters and liver and kidney samples were collected for histopathological analysis. The results indicate that cinnamon aqueous extract exhibit a highly significant preventive potential by ameliorating APAP-induced elevated levels of serum alanine aminotransferase, aspartate aminotransferase, creatinine, urea and macroscopic and histological alterations in liver and kidney. Moreover, significant increase in total oxidant status and decrease in total antioxidant capacity accompanied by APAP exposure, were restored by cinnamon pretreatment. We found that prior administration of cinnamon prevented the toxic changes induced by acetaminophen as confirmed by histopathological examination, more possibly owing to its antioxidant potential. In conclusion, the pretreatment with cinnamon provide potential therapeutic applications in acute liver and kidney injury induced by APAP in experimental animal model and it could have therapeutic potential in oxidative stress associated diseases. [ABSTRACT FROM AUTHOR]

Magnetoelectric multiferroics, which combine ferroelectric and magnetic characteristics, have potential use in a variety of electronic devices. In this work, Dy3+ substituted bismuth ferrites with the chemical formula Bi 1−x Dy x FeO 3 (x = 0.0, 0.15, 0.30, 0.45, and 0.60) were synthesized using the sol-gel auto combustion process. The effect of Dysprosium substitution in BiFeO 3 (BFO), on its structural, surface morphology, optical, electrical, dielectric, ferroelectric, and magnetic properties were studied. The rhombohedral perovskite structure of the space group (R3c) was confirmed via X-ray diffraction (XRD) analysis. Moreover, the crystallite size had a maximum value of 59.57 nm for x = 0.30. XRD and FTIR confirmed the substitution of Dy3+ into BFO ferrite. Further, the structural change and absorption bands confirmed the substitution of Dy3+ ions into the lattice. For x = 0.30, the energy bandgap of 2.81 eV was found. The resistivity and activation energy were minimum and drift mobility was maximum at x = 0.30 as compared to Dy3+ doped BFO samples. At low frequency, the dielectric loss was reduced, while at high frequency, the dielectric loss increased with increasing frequency. The saturated polarization (P S), electric polarization (E C), and remnant polarization (P r) have values of 6.95 µC/cm2, 3.49 µC/cm2, and 1.53 kV/cm for x = 0.30, respectively. The maximum saturation magnetization and microwave frequencies were 10.89 emu/g and 2.41 GHz, respectively at Dy3+ concentration x = 0.30. These materials are suitable for electronic and microwave devices. • Bi 1- x Dy x FeO 3 (x = 0.0, 0.15, 0.30, 0.45, and 0.60) multiferoaic were successfully prepared via simple sol-gel auto-combustion. • The optical bandgap energy has values between 2.71.71 eV and 2.93 eV. • The ferroelectric nature of the samples was confirmed using the P - E loop. • Maximum magnetization saturated is observed ~ 13 emu/g. • The maximum microwave frequency has values between 1.39.39 GHz and 2.88 GHz. [ABSTRACT FROM AUTHOR]

Lanthanum doped Z n 0.5 C o 0.5 L a x F e 2 − x O 4 spinel ferrites were synthesized through the co-precipitation technique. To characterize the structural, vibrational, electro-optical, dielectric, and thermoelectric properties, the following characterization techniques X-ray diffraction (XRD), Fourier transformation infrared (FTIR) and Raman spectroscopy, I–V measurement analysis, UV–vis spectroscopy, LCR meter, Seebeck analysis, and Energy dispersive X-ray analysis (EDX) were used. The XRD patterns showed nano-crystalline single-phase structure formation. Moreover, the lattice constant increased from 8.3909 ± 0.0042 Å to 8.3994 ± 0.0042 Å, and the crystallite size reduced from 33.6 to 17.5 nm with increasing La3+ cations. The bond angles showed stronger A – A and A – B interactions and weak B – B interactions with the addition of La3+. FTIR spectra showed the existence of the M − O stretching band and functional group study. The resistivity, optical band gap, and activation energy had maximum values at x = 0.1. At room temperature (RT), the dielectric parameters were recorded between the range of 8 Hz to 8 MHz. The Seebeck voltage coefficient was obtained for the as-prepared nano-ferrites to determine the charge carrier type. The EDX spectra showed a compositional distribution of the elements in all the samples. • Z n 0.5 C o 0.5 L a x F e 2 − x O 4 nano ferrite powder was prepared via the co-precipitation route. • Single-phase crystal structure and crystallite size decreased with La3+ in Zn–Co ferrites. • The optical band gap and DC resistivity were maximum at x = 0.1. • Z n 0.5 C o 0.5 L a 0.1 F e 1.9 O 4 has a small dielectric tangent loss at low frequency. [ABSTRACT FROM AUTHOR]

Lanthanum substituted Mg–Ni–Cu–Co ferrite nanoparticles prepared through the Sol-Gel method were studied using different methods such as XRD, FTIR, UV-VIS, SEM, Raman, LCR, EDX and IV to evaluate the structural, optical and electrical properties. The single-phase cubic spinel structure of the prepared samples was confirmed from X-ray diffraction analysis. The FT-IR spectra indicated two absorption bands, ν 1 and ν 2 that represent the complex Fe3+–O2− at A-site (tetrahedral) and B-site (octahedral) vibration. The optical band gap decreased from 2.48eV to 1.53eV observed by UV–Vis, and matched with the electrical resistivity measurements. Variation in the lattice parameters from XRD, the absorption band (octahedral) from FTIR, the optical energy band gap from the UV–vis data and the DC resistivity demonstrated change in structural, optical and electric properties of Mg–Ni–Cu–Co ferrites nanoparticles due to the addition of the rare earth element La3+. Both the dielectric losses and dielectric constant of the prepared samples decreased due to the La3+ ions doping, and A.C conductivity increased with increasing the value of frequency from 8 Hz to 8 M Hz. The variation in Raman peaks reveals that Raman shift varied due to the La3+ addition. EDX data confirmed the stoichiometric calculations of La3+ions substituted into Mg–Ni–Cu–Co ferrite nanoparticles. [ABSTRACT FROM AUTHOR]