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Pure and nickel (Ni) doped cobalt oxide nanoparticles were employed by the co-precipitation method to present the structural, optical, and photocatalytic characteristics of NixCo3-xO4 nanoparticles (x = 0, 0.05, 0.1, and 0.3) for organic pollutant photodegradation. X-ray diffraction (XRD) was employed on NixCo3-xO4 samples with particle sizes ranging from 14 to 22 nm, confirming the occurrence of cubic phase. In addition, particle size was calculated by Debye Scherrer, Williamson-Hall (W-H) and Halder methods, respectively. The Fourier transform infrared (FTIR) analyses of all samples characterised the inherent lattice vibrations of spinel structures octahedral and tetrahedral sites, respectively. FESEM image depicts irregular-shaped clusters and EDX confirmed the presence of Ni, Co and O elements. The mesoporous nature of the pores and high BET specific surface area indicated the presence of several active sites, proving their viability as photocatalysts. UV-Vis spectrophotometer was utilised to measure the optical properties, which included recording absorption spectra and computing optical parameters. The photocatalytic activities of the pure Co3O4 and NixCo3-xO4 photocatalysts were studied by the degradation of a series of four dyes (Congo Red, Tartrazine, Rhodamine B, and Methylene Blue) solution under visible light irradiation. Compared to pure cobalt oxide, Ni-incorporated Co3O4 exhibits a substantially higher photocatalytic efficiency that increases with Ni doping concentration. The photocatalysts displayed superior recycling stability, retaining high performance after three cycles. The photosensing properties were investigated under UV light, and a considerable photocurrent enhancement was observed. As a result, it is illustrated that Ni-doped cobalt oxide NPs are a potential material for the fabrication of photosensitive devices. [ABSTRACT FROM AUTHOR]

The study presents a comprehensive investigation into the synthesis, characterization, and application of barium strontium titanate-calcium copper titanate (BST-CCTO) heterojunction, offering insights into their potential for high-energy-density capacitors and photocatalytic applications. It discusses the synthesis methods for BST, CCTO nanoparticles and their heterojunction. It delves into the structural analysis of prepared heterojunctions using techniques like X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The photocatalytic performance of heterojunctions, particularly in the degradation of organic dyes and pharmaceutical waste under visible light, is explored. Results demonstrate the superior photocatalytic efficiency of BST-CCTO heterojunction, i.e., B2 (99.5 % for RhB) compared to individual BST (78.4 %), suggesting potential applications in environmental remediation. This study also explores the development and properties of dielectric materials, particularly focusing on polyvinylidene fluoride (PVDF) and its composites with high-dielectric ceramics such as BST and CCTO. Various aspects of dielectric behavior, including polarization mechanisms and frequency dependence, are also discussed. Dielectric studies reveal the enhanced dielectric constant (50.93 at 1 kHz for 3 wt% loading of B3) of PBCT-3 composite as compared to pure PVDF composite (10 at 1 kHz), attributed to factors such as interface engineering, complementary electrical properties, and grain boundary effects. The mechanisms underlying the interaction between fillers and PVDF matrix are elucidated, highlighting the role of interface engineering and polarization enhancement in optimizing dielectric performance. [ABSTRACT FROM AUTHOR]

In this work, the optimized structure parameters, and vibrational wavenumbers of (2E)-1-(3-Bromothiophen-2-yl)-3-(2, 3, 5-trimethoxyphenyl) prop-2-en-1-one (BTTP) molecule have been predicted by Density Functional Theory (DFT) method with B3LYP/6–311++G (d,p) basis set. The calculated vibrational wavenumbers have been compared with observed FT-IR (4000 − 400 cm−1) and FT-Raman (3500 − 100 cm−1) wavenumbers. The difference between the observed and the scaled wavenumber values of most of the fundamentals is very small. Using the aid of VEDA 4 software, the vibrational assignments were made using potential energy distributions. The calculated HOMO, LUMO energies and energy differences demonstrate that charge transfers take place within the molecule. The stability of the molecule arising from hyperconjugative interactions, and charge delocalization have been analyzed using natural bond orbitals (NBO) analysis. The results provide that charge in electron density (ED) in the bonding, and antibonding orbital and second order delocalization energies E(2) confirms the occurrence of intramolecular charge transfer (ICT) within the molecule. Thermodynamic parameters such as entropy (S), enthalpy changes (ΔH) and heat capacity at constant pressure (Cp) are calculated in the temperature range from 100 to 700 K. The first hyperpolarizability (β), dipole moment (μ), and polarizability (α) values are being used to confirm the nonlinear optical behavior of the molecule. In addition, the dielectric properties explain the interactions between the sample and solvent at high frequencies. Finally, the compound is taken for the docking studies and molecular docking was performed against the potential target protein tankyrase and the results are compared with the drug Warfarin. The anticancer activity of BTTP confirms that it can be treated as antineoplastic against the two tested cell lines. [ABSTRACT FROM AUTHOR]

Depletion of lithium resources has forced scientists to search for alternative energy storage chemistries. Gel polymer electrolytes (GPEs) are being explored as an important option due to their leakage-free and superior electrochemical performance. The present work is focused on examining the impact of adding ionic liquid EMIM-BF4 (1-ethyl-3-methylimidazolium tetrafluoroborate) on the electrochemical behavior of sodium-ion conducting GPEs containing ethylene carbonate and polypropylene carbonate solvents, poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) polymer, and sodium tetrafluoroborate (NaBF4) salt. The electrochemical behavior of the prepared GPEs is studied by complex impedance spectroscopy and other electrochemical studies. With the accumulation of 10 wt.% of EMIM-BF4, the ionic conductivity is greatest, and increases from ~1.94 × 10−3 S cm−1 to a maximum of ~7.98 × 10−3 S cm−1 at room temperature. The electrochemical stability window (ESW) of the GPE is ∼ 4 V. To study the structural modification in electrolytes, Fourier transform infrared (FTIR) spectroscopy and x-ray diffraction (XRD) are conducted. The real and imaginary parts of permittivity and modulus behavior over a wide frequency range are also investigated and described. [ABSTRACT FROM AUTHOR]

Copper selenide (Cu2Se) is a promising semiconductor with notable potential for optoelectronic and thermoelectric applications. This study investigates the impact of film thickness on the physical properties of Cu2Se thin films. Cu2Se thin films of varying thicknesses were synthesized using the thermal evaporation technique. These films were then analyzed for optical properties, structural characteristics, and surface morphology. Optical analysis was conducted using absorption spectra over a wavelength range of 200 to 900 nm. From these spectra, we determined key optical parameters such as the energy band gap (Eg), extinction coefficient (k), and refractive index for films of different thicknesses. Dielectric properties were evaluated, allowing us to calculate the dielectric constant and dielectric loss for various film thicknesses. Additionally, current–voltage (I-V) characteristics and Raman spectroscopy were performed, and the results are presented and discussed in detail. [ABSTRACT FROM AUTHOR]

Doping is a widely explored technique to modify the properties of semiconducting materials. In the case of tungsten trioxide (WO3), doping with elements such as SnO2 and SrO has garnered significant attention owing to its potential impact on structural, functional, and optical characteristics. We report on structural, functional, optical, and dielectric properties of SnO2/WO3 and SrO/SnO2/WO3 composites and, for comparison, WO3 prepared via a wet chemical method. Crystallite phases were confirmed using x-ray diffraction patterns. Fourier-transform infrared spectroscopy and dielectric studies were employed to analyze the functional groups, dielectric constants, and losses of the SnO2/WO3 and WO3/SnO2/SrO composites. Ultraviolet-visible spectroscopy and photoluminescence spectroscopy were used to examine the optical absorption and emission maxima, respectively. The energy bandgap was determined from the absorption spectra by using a Tauc plot. Additionally, all the prepared composites exhibited brighter and sharper narrow emissions in the photoluminescence spectra. Dielectric studies of WO3/SnO2/SrO composites revealed slightly better dielectric constants and lower dielectric losses than those of SnO2/WO3 composites. Our findings suggest that the prepared composites are suitable for use in sensor and optoelectronic device applications. [ABSTRACT FROM AUTHOR]

Bio‐based flexible dielectric substrates have gained tremendous attention for their potential to reduce environmental risks from nonbiodegradable electronic waste. The present study demonstrates the fabrication of facile, nontoxic, and biodegradable chitosan‐based flexible dielectric substrate using graphene nanoplatelet (GNP) as a nanofiller. The detailed impact of different concentrations of GNP (1, 2, and 3 wt%) into the chitosan (CS) matrix was studied on physicochemical, morphological, mechanical, electrical, and thermal properties. The fabricated CS/GNP composites showed improved mechanical strength, thermal stability, and electrical properties compared with unmodified CS film. The composites exhibited excellent thermal stability (200°C) with a promising biodegradation rate (within 6 days). The mechanical strength of the unmodified CS film was increased unequivocally with 2 wt% GNP loading with tensile strength of 23.56 Mpa. Furthermore, the current–voltage (I–V) characteristic curves for CS/GNP (2%) and CS/GNP (3%) showed similar current conduction and ohmic behavior in flat, bending, and flat‐after‐bending modes. The dielectric measurements revealed that the CS/GNP composite with 2 wt% filler exhibited optimal performance having permittivity (έ) of 32.71 (at 102 Hz) with low dielectric loss of 0.04 (at 106 Hz). These results suggest that the dielectric films offer strong prospects as an eco‐friendly alternative for various applications. Highlights: Biodegradable chitosan‐based flexible dielectric films were prepared.Films were made using a simple solvent casting method with 1–3 wt% GNP filler.Optimum physicochemical and electrical properties were seen at 2 wt% GNP.CS/GNP (2%) film exhibited ohmic behavior in both flat and bending modes.Excellent dielectric properties were achieved at 2 wt% GNP filler. [ABSTRACT FROM AUTHOR]

Nanocrystalline cobalt ferrites co-substituted with rare earth Ho and Er (CoFe 2-2 x Ho x Er x O 4 , 0 ≤ x ≤ 0.10) have been synthesized via the sol-gel method. X-ray Diffraction (XRD) confirmed the single-phase spinel structure with reduced crystallite sizes (65 nm–12 nm), micro-strain (ε) and increased lattice constant (a) with Ho–Er co-substitution. Rietveld refinement and theoretical computation revealed Ho and Er occupancy at octahedral sites and Fe and Co ions redistribution between the tetrahedral and octahedral sites. Infrared spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray spectroscopy (EDX) and X-ray Photoelectron Spectroscopy (XPS) supported the formation of the desired spinel structure, aggregated spherical morphology, chemical stoichiometry and elemental states. Magnetic measurements showed a systematic decrease in saturation magnetization (M s), magnetocrystalline anisotropy (K 1), coercivity (H c) and Curie temperature (T c) with Ho–Er co-substitution. Electron Spin Resonance (ESR) exhibited asymmetric resonance peaks, reduced resonance field (H r), linewidth (ΔH pp) and deviation in Lande g values. Impedance spectroscopy revealed two conduction mechanisms (holes and electrons) with distinct activation energies (E aI and E aII). Modulus spectrum analysis confirmed the thermally activated sample-electrode effects and the Nyquist plots indicated the dominant contribution of the grain boundary resistance to the conduction process. A notable enhancement in the dielectric constant (ε′) was observed with Ho–Er co-substitution. The ac conductivity (σ ac) followed the Jonscher Power Law (JPL). The temperature-dependent frequency exponent s(T) , suggests the existence of two conduction mechanisms: non-overlapping small polaron tunneling (NSPT) and correlated barrier hopping (CBH). [ABSTRACT FROM AUTHOR]

This study demonstrates the successful synthesis of SrZr(PO4)2:Dy2O3 solid solutions via solution combustion method, employing glycine as fuel. Powder X-ray diffraction (XRD) confirmed the crystal structure, while scanning electron microscopy (SEM) provided detailed insights into the surface morphology. Fourier transform infrared (FT-IR) spectroscopy identified the functional groups present, further revealing the material's composition. Photoluminescence (PL) measurements reveal excitation bands at 350, 365, 390, 425, and 450 nm; emission bands at 480, 580, and 665 nm. Emission color of the sample plot in the CIE x,y co-ordinates reveal white emission close to the standard white (0.33,0.33) demanded by the international television committee. Finally, dielectric studies revealed promising potential for long-term energy storage applications, particularly in super-capacitors. [ABSTRACT FROM AUTHOR]

Nickel substituted Sr–Co nano spinel ferrites with composition Sr 0.5-x Ni x Co 0.5 Fe 2 O 4 (0.0, 0.1, 0.2, and 0.3) were prepared with the help of a sol-gel auto combustion route. The prepared materials were sintered at 800 for four and a half hours. Analysis of XRD confirmed that the material is composed of a cubic spinel structure with a single phase, and its space group is Fd-3m. Rietveld refinement of X-ray diffraction data was done for all prepared compositions using FULLPROF software. As the composition under study contains more nickel than lattice constant, crystalline size, X-ray density, and bulk density decrease. The dielectric properties were observed about frequency. The dielectric properties revealed that dielectric loss, dielectric constant, and ac conductivity decrease with increasing the Ni2+ content. The activation energy (ΔE) was calculated from the slope of Arrhenius plots. The ΔE found in the range of 0.580–0.096 eV. The analysis of XPS was carried out to examine the elemental state of annealed samples. The prepared material is suitable for employment in applications involving high frequencies because the Ni-doped Sr–Co ferrites with the greatest Ni2+ concentration have the lowest dielectric loss, dielectric constant, and tangent loss value. [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]

A graphene quantum dot (GQD)-decorated ZnFe2O4 hybrid nanocomposite [GQD-ZHN] was synthesized using the sol–gel technique. In the X-ray diffraction (XRD) analysis, a cubic spinel structure was identified with the space group Fd-3 m. Fourier-transform infrared (FT-IR) analysis revealed the vibration bands of the samples, while the existence of GQDs in GQD-ZHN was confirmed by the Raman spectra. Field emission scanning electron microscopy (FESEM) provided insights into the microstructural morphological topology of the surface. The dielectric properties of GQD-ZHN were analysed with respect to their dependence on frequency and temperature and explained by Maxwell–Wagner-type polarization. The frequency-dependent ac conductivity (σac) followed Jonscher's power law and investigated the dynamics of ion hopping in GQD-ZHN. Impedance and modulus spectroscopy were used to further evaluate electrical characteristics such as relaxation time (τ). Nyquist plots have been used to estimate grain and grain boundary contributions. The GQD-ZHN exhibited superparamagnetic properties at room temperature. At room temperature, GQD-ZHN exhibited a strong magneto-dielectric coupling (MD) and showed negative magneto-dielectric properties in low-frequency regions. These properties of GQD-ZHN enable it to be used as a potential application in microelectronic systems, spintronics and memory devices. [ABSTRACT FROM AUTHOR]

Cobalt based nanoferrites Co1−xCuxCeyFe2−yO4 where x = 0.0 to 0.5 with 0.1 nano-ferrites synthesized through citrate gel auto combustion technique and their structural and topographical studies were inspected through X-ray diffraction technique and field emission scanning electron microscope. The structural analysis confirms the prepared nano-ferrites having single-phase cubic spinel, along Fd3m space group. Crystalline size of the synthesized samples found 20–26 nm calculated by Debey Scherrer formula. The FTIR spectrum reveals prominent absorption bands ʋ1 and ʋ2 within the wavenumber range below 1000 cm−1, denoting tetrahedral and octahedral voids. The Raman spectrum of AB2O4 exhibits lattice vibrations expressible through 5Tu1 + A1g + Eg + 3T2g representations for the Fd3m space group, predicted via group theory. Electrical properties were measured by LCR meter. The AC conductivity of the materials increased as increasing frequency. Magnetic behavior of the materials measured by a vibrating sample magnetometer, saturation magnetization gradually decreases as increasing Cu and Ce content and found to be 26 to 18 emu/gm. Catalytic activity of the samples confirmed by dye degradation studies of methylene blue and acid red dye degradation. The sample Co0.9Cu0.1Ce0.1Fe1.9O4 exhibits the highest catalytic degradation activity for methylene blue and acid red. [ABSTRACT FROM AUTHOR]

In the years 1990–2015, many liquid crystalline (LC) substances were studied under elevated pressure. The main aims of studies were to determine the P vs. T phase diagrams, the equation of state V(P,T) for isotropic and LC phases, measuring the dynamical properties of molecules (mainly the flip-flop motions) and analysing them at the isobaric, isothermal and isochoric conditions. The observed phenomena were discussed using existing theoretical models of LC state or – in the absence of them – models adopted from the field of glass-forming liquids. In the present review, the attention will be paid to a comparative data analysis for two rings compounds with the strongly polar terminal group (CN or NCS) at one site and the n-alkyl or n-alkoxy group at the other. Such molecules may well mimic the rod-like molecules commonly used in theoretical models of LC state. [ABSTRACT FROM AUTHOR]

We report the effect of titanium doping on the structure, morphology, dielectric and electrical properties of zirconium ferrite Zr1−xTixFe2O4 (x = 0.0, 0.01, 0.03, 0.05) nanocrystalline ceramics prepared via sol–gel method. X-ray diffraction (XRD) technique confirmed the spinel structure of all samples and that the average crystallite size decreased with Ti doping. Scanning electron microscopy (SEM) confirmed the spherical-shaped morphology with an average grain size of 300 and 200 nm for x = 0 and 0.05, respectively. The Raman study revealed that Ti4+ substitution slightly shifts the Raman modes towards the lower wavenumber. The dielectric studies analyzed using Impedance analyzer show the increase in dielectric parameters such as dielectric constant and dielectric loss with Ti concentration. The complex impedance analysis in the frequency range (10–106 Hz) is analyzed to understand the interactions from the grain and grain boundary phases. The dielectric feedback and impedance analysis studied the electrical properties in the 300–700 K temperature range and frequency range of 20–106 Hz. The AC conductivity increases with applied frequency and decreases with doping concentration. It is found that the Ti concentration increases the activation energy determined using the Arrhenius equation of AC conductivity and is a characteristic of polaron conduction. The Universal power law dependency of AC conductivity indicates charge transport made possible by hopping or tunneling. The temperature-dependent frequency exponent n's observed minimal implies that the major transport mode is significant polaron tunneling. [ABSTRACT FROM AUTHOR]

Single crystals of bimetallic 1-D coordination polymer, NiZnEDTA were grown by the single gel diffusion method. The agar-well diffusion technique and MTT assay test were done to examine the antimicrobial and anticancer activity of NiZnEDTA. The test outcomes of the MTT assay give a preliminary indication of the anticancer potential of the sample on MDA-MB-231 cells and its nontoxic nature to normal L929 cells. The third-order nonlinear optical characterization of NiZnEDTA was studied by Z-scan technique.

The development of an environment-friendly process for synthesizing nanoparticles in the field of bionanotechnology is growing day-by-day. Increasing drug resistance in microbes has compelled researchers to synthesize biologically active nanoparticles. In this study, we used Tribulus terrestris plant extract to synthesize CuO/NaCuSO4 nanocomposite. The synthesized samples were characterized through functional groups analysis of FTIR and morphological analysis of SEM. The X-ray diffraction (XRD) and ultra-visible light absorbance analysis (UV–vis) were used to find the nanocrystalline nature and bandgap energy of the biosynthesized copper oxide (CuO) nanoparticles, respectively. In the metal oxide region of Fourier transform infrared (FTIR) spectroscopy the copper oxide nanoparticles were confirmed at 523 cm−1 which showed the nature of plant extracts to control over the reduction and stabilizing of the nanoparticles. The Rietveld refinement analysis yielded unit cell compositions of 53.39% for CuO and 46.61% for NaCuSO4, respectively. The monoclinic structure of CuO was confirmed, and the crystalline size was calculated as 37 nm by XRD analysis. From UV–vis spectroscopy, the absorption peak was observed at 277 and 337 nm, revealing the presence of CuO nanoparticles. In fact, the cluster-like morphology patterns are captured by scanning electron microscopy (SEM) and particle sizes were observed around 102 nm. Finally, the dielectric properties of the synthesized copper oxide nanoparticles have been examined and reported in detail. [ABSTRACT FROM AUTHOR]

In the present work, we have synthesized rare-earth ion modified Bi4−xRExTi2Fe0.7Co0.3O12−δ (RE = Dy, Sm, La) multiferroic compounds by the conventional solid-state route. Analysis of X-ray diffraction by Rietveld refinement confirmed the formation of a polycrystalline orthorhombic phase. The morphological features revealed a non-uniform, randomly oriented, plate-like grain structure. The peaks evident in the Raman spectra closely corresponded to those of orthorhombic Aurivillius phases. Dielectric studies and impedance measurements were carried out. Asymmetric complex impedance spectra suggested the relaxation of charge carriers belonging to the non-Debye type and controlled by a thermally activated process. Temperature-dependent AC conductivity data showed a change of slope in the vicinity of the phase transition temperature of both magnetic and electrical coupling natures. Based on the universal law and its exponent nature, one can suppose that the conduction process is governed by a small polaron hopping mechanism but significant distortion of TiO6 octahedral. The doping of the A-sites with rare-earth element ions and changes in the concentrations of Fe and Co ions located on the B-sites manifested themselves in saturated magnetic hysteresis loops, indicating competitive interactions between ferroelectric and canted antiferromagnetic spins. The magnetic order in the samples is attributed to pair-wise interactions between adjacent Fe3+–O–Fe3+, Co2+/3+–O–Co3+/2+, and Co2+/3+–O–Fe3+ ions or Dzyaloshinskii–Moriya interactions among magnetic ions in the adjacent sub-lattices. As a result, enhanced magnetoelectric coefficients of 42.4 mV/cm-Oe, 30.3 mV/cm-Oe, and 21.6 mV/cm-Oe for Bi4−xDyxTi2Fe0.7Co0.3O12−δ (DBTFC), Bi4−xLaxTi2Fe0.7Co0.3O12−δ (LBTFC), and Bi4−xSmxTi2Fe0.7Co0.3O12−δ (SBTFC), respectively, have been obtained at lower magnetic fields (<3 kOe). The strong coupling of the Aurivillius compounds observed in this study is beneficial to future multiferroic applications. [ABSTRACT FROM AUTHOR]

An effect of Cu-doped Ni-Zn nanoferrite particles synthesized through the citrate gel auto-combustion method on structural dielectric and magnetic properties was investigated. The structural characterization of synthesized powder is investigated using XRD (X-ray diffraction), FE-SEM (field emission scanning electron microscopy), EDXS (energy-dispersive X-ray spectroscopy), AFM (atomic force microscope), and TEM (transmission electron microscope). All prepared samples were established to have a single-phase spinel structure and fine grain size with an Fd-3 m space group. The lattice parameter, volume, and crystallite size decrease with increasing copper substitution. By adding copper ions, the surface area rises from 123.9 to 187.4 m2 g−1. The surface roughness is increased by AFM examination from 7.6 to 11 nm. From the AFM samples, it is shown that they are soft to hard in nature due to the Cu doping. The real imaginary impedance and the complex electric modulus were studied within the frequency range of 20 Hz to 1 kHz at room temperature, respectively. In the Cole–Cole plots studied for dielectric constant, it was observed that all samples had single semi-circles and continuously decreased with increasing copper content. This shows that the prepared material is good for high-resistance applications and the fabrication of multilayer inductor chips. The magnetic characteristics of hysteresis loops were studied at room temperature using a VSM (vibration sample magnetometer) for nanoferrites. The prepared ferrites samples were examined; copper doping increased the width of the loops, which confirms the change from soft to hard magnetic material. They are utilized in data processing, telecommunications, and the automobile industries. At low temperatures, the prepared samples showed superparamagnetic behavior. It is used in medical and electrical device applications. [ABSTRACT FROM AUTHOR]

In this work, we report the synthesis of α-Fe2O3, ZnO, and α-Fe2O3/ZnO nanomaterials by a simple sol-gel method for photocatalytic dye degradation and flexible electronic applications. X-ray diffraction results reveal that the synthesized samples were rhombohedral and hexagonal wurtzite structures of α-Fe2O3, and ZnO nanoparticles, respectively. α-Fe2O3/ZnO composites exhibit the mixed peaks of both α-Fe2O3 and ZnO crystal structures which substantiate the formation of α-Fe2O3/ZnO composites. From the optical studies, the band gaps of α-Fe2O3, ZnO, and α-Fe2O3/ZnO composites of (1:1) and (1:2) ratios are calculated as 2.11, 3.14, 2.87, and 2.92 eV respectively. Compared to pure α-Fe2O3 and pure ZnO nanoparticles, α-Fe2O3/ZnO composites of (1:2) ratio exhibit superior photocatalytic behavior under the irradiation of the natural sunlight and also show good stability for up to five cycles. From the scavenger studies, it is concluded that hydroxyl radicals are the major contributors to the photocatalytic degradation of methylene blue dye molecules. The dielectric behavior of the pure and blended nanoparticles is also investigated in a wide range of frequencies using impedance spectroscopy. The nanoparticles embedded in polyvinyl alcohol (PVA) or α-Fe2O3/ZnO/PVA thin films demonstrate a higher dielectric constant (32.68) and lower loss factor (3.32) than pristine PVA. The AC conductivity (σAC) of α-Fe2O3/ZnO composites of (1:2) ratio is 10−12 S/cm. These findings indicate the possibilities of using α-Fe2O3/ZnO/PVA composites for the fabrication of flexible electronic devices. [ABSTRACT FROM AUTHOR]

Gadolinium-doped cobalt ferrite CoGdxFe2-xO4 (CGF) were produced using citrate gel auto-combustion method (x = 0–0.025 at an interval of 0.005). An investigations on the impact of Gd3+ ions on structural, dielectric, and magnetic properties were conducted. The synthesized materials were characterized using the following techniques: X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, ultraviolet visible spectroscopy (UV), impedance (dielectric) analysis, and vibrating sample magnetometer (VSM). The crystalline size ranging from 48 to 13 nm. The Williamson-Hall plots were utilized to examine the impact of crystalline size and lattice strain on the peak broadening of each sample. The X-ray diffraction spectra were used to confirm phase identification and spinel structure. The results of FTIR examinations show that strong metal oxide bonds can be found in the tetrahedral and octahedral sites at wavelengths of 351–376 cm−1 and 567–574 cm−1, respectively. The obtained samples to study optical energy bandgap (Eg), which vary from 2.01 eV to 2.45 eV and show that they are semiconducting materials.The Maxwell-Wagner model and Koop's theory have both been used to study the behaviour of dielectric properties. The dielectric constant at room temperature to 673 K in the frequency range 50 Hz–1 MHz to study the dielectric constant, dielectric loss, AC electrical conductivity, and impedance. The impedance charts show how conductivity was impacted by grain and grain boundary mechanisms. In relation to an applied field of 100 kOe, magnetization was measured at 3 K and 300 K. The blocking temperature (TB), which exhibits super-paramagnetic behaviour, is found to be approximately 359 K according to zero-field cooling ZFC and field cooling. The FC experiments carried out in the temperature range of 3 K–360 K under an applied field of 100 Oe.

Nano-crystalline powders of Bi(1-x)TrxFe(1-y)MnyO3 (where x & y = 0, 0.05 and Tr = Cr, Ni, Zn, Cu) were prepared using sol-gel autocombustion method. Structural studies on the calcined nanopowders using X-ray diffraction and Fourier transform infrared spectroscopy confirm the perovskite phase with rhombohedrally distorted structures. Microstructural studies using scanning electron microscopy and energy dispersive spectroscopy on the sintered surfaces display uniformly knitted fine grained microstructures with thin grain boundaries and the presence of all element's constituent for the synthesis of the samples, respectively. Dielectric properties were evaluated at various frequencies and temperatures and found to follow space charge polarization with significantly reduced dielectric losses at all frequency ranges investigated. Impedance study on the samples aids in understanding the contributions of electrical conductivity and interfacial polarization, and the results verify the claims explained during the dielectric property investigation. Magnetic studies on the samples reveal that among all the samples, Cr/Mn co-doped (BCrFMO) sample shows significant enhancement in the value of saturation magnetization (3.718 emu/g) while Ni/Mn co-doped (BNiFMO) sample demonstrates higher coercivity (259.734 Oe) at room temperature. With all enhanced structural, microstructural, dielectric and magnetic order through the influence of co-doing, these materials are highly recommended for spintronic, multifunctional memories, sensors, and actuators. Highlights: Wet chemical synthesis of sol-gel autocombustion produced Bi(1-x)TrxFe(1-y)MnyO3 (where x & y = 0, 0.05 and Tr = Cr, Ni, Zn, Cu) multiferroic samples with co-doping effect were studied for the first time. XRD and FTIR data shows that all samples have rhombohedral-symmetric single-phase perovskite structures. Co-doping boosts magnetic order in all Cr, Ni, Zn, Cu and Mn co-doped samples. Highest magnetization value of 3.718 emu/g was evident in Cr-Mn co-doped bismuth ferrite (BCrFMO) sample. [ABSTRACT FROM AUTHOR]

In this work, we have grown an organic nonlinear crystal of 4-methylpyridinium 2, 4-dinitrophenolate with reasonable size by slow evaporation solution growth method using ethanol solvent at ambient temperature. A well-developed surface crystal was selected for characterization studies, and single-crystal X-ray diffraction analysis provided a centrosymmetric monoclinic crystal structure. Various functional groups and different vibrational modes were identified using Fourier transform-infrared spectroscopy studies. Fluorescence emission declares that 4MPDNP crystal serves as a photoactive material. The optical transparency and optical band gap energy were examined by the UV–visible spectrum. Thermogravimetric and differential scanning calorimetry analyses were employed to understand the thermal and physio-chemical stability of the title compound. The relative dielectric permittivity and laser damage threshold of the grown crystal were measured by LCR/impedance analyzer and Q-switched Nd: YAG laser, respectively. The magnitude of third-order nonlinear optical parameters was evaluated by the Z-scan technique. [ABSTRACT FROM AUTHOR]

The research article investigates the effect of incorporating the guanidinium carbonate (GuC) salt into the poly vinylpyrrolidone (PVP) and polyethylene oxide (PEO) polymer matrix. Various weight percentages of GuC enriched PVP/PEO solid polymer electrolytes (SPEs) have been prepared by the simplest solution casting process. XRD analysis revealed that the incorporation of the GuC salt led to changes in the crystalline structure of the PVP/PEO. FTIR analysis confirms the presence of guanidinium carbonate in the blended polymeric system. FESEM imaging showed the uniform and smooth surface view of the electrolytes. DSC analysis suggests that the addition of the GuC led to a decrease in the melting temperature and an increase in the crystallisation temperature. The temperature-dependent dielectric analysis showed that the presence of the organic salt led to an increase in the dielectric constant of the polymer blend. Among all the prepared electrolytes, 25 wt.% GuC added polymer electrolyte achieved a higher conductivity of 3.00764 × 10−7 S/cm. Overall, the results of the study suggest that the incorporation of the GuC salt into the PVP/PEO can lead to significant changes in the structural, thermal, and dielectric properties of the blend. These findings have potential implications for the use of PVP/PEO blends in solid state battery applications.

Magnesium substituted Li-ferrites nanoparticles with chemical composition Li 0.5-0.5 x Mg x Fe 2.5-0.5 x O 4 (x = 0.0, 0.2, 0.4, 0.6, 0.8, and 1) synthesized by sol-gel auto combustion method. Synthesized materials were sintered at 600 °C for 4 h in the air and heated samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive x-ray spectroscopy (EDS) techniques. Rietveld refinement of XRD patterns confirmed the formation of the spinel structure where the lattice constant varied with the increase of Mg content. The crystallite size of magnesium-substituted lithium ferrites was calculated using Scherrer's equation and showed slight changes while the W-H plot shows more changes. The electrical conductivity and activation energy of Mg-substituted lithium ferrite were strongly affected by Mg content and by which they appear to confirm to semiconductor nature. The paramagnetic transition to ferrite was confirmed by the change in the Arrhenius plot, which showed a large variation between two regions that differ in the values of the activation energy, where the values of activation energies in the ferrite region were greater than those that appeared in the para region, as well as the variation between the activation energy values in the non-substituted lithium ferrite. The dielectric parameters such as the real part of the dielectric constant and loss tangent of the samples were analyzed in the range of 50 Hz to 5 MHz at room temperature, 100, 300, and 500 °C. Curie's temperature showed a decrease with the increase in Mg content. Hysteresis loops were measured using a vibrating sample magnetometer (VSM) where both the temperature and the applied magnetic field were changed. The FC result of Li 0.5-0.5 x Mg x Fe 2.5-0.5 x O 4 (x = 0.2, 0.4, and 0.6) is almost flat below T B which demonstrates that the Li–Mg nano ferrites show a super-spin glass behaviour. [ABSTRACT FROM AUTHOR]

Electromagnetic radiation interference (EMI) or pollution is increased significantly in proportion to the expansion of electronic and communication industries, which lead to the disturbance of the functioning of electronic gadgets and medical equipments, in addition to the human health damage. The Microwave absorbing (MA) composite comprised of polyvinyl alcohol (PVA), polyaniline (PANI), carbon nanotube (MWCNT) and iron oxide (Fe3O4) has been developed with various proportions, denoted as PVA/PANI/MWCNT/Fe3O4 (1%, 3%, 5%). Fe3O4 was prepared using a hydrothermal method, and PVA/PANI/MWCNT/Fe3O4 (1%, 3%, 5%) nanocomposites was made by solvent casting techniques. The PVA composite films were also subjected to a range of analyses including IR, TGA, DTA, DTG, SEM, TEM, dielectric measurements and EMI shielding effectiveness (EMI SE), to describe their characteristics. The results of various studies indicate that the PVA/PANI/MWCNT/Fe3O4 (1%, 3%, 5%) composites possess enhanced thermal and dielectric characteristics, for instance the PVA/PANI/MWCNT/5% Fe3O4 blend nanocomposites possess 10% initial decomposition at 220°C and dielectric constant of 3.2 × 107 at 1 MHz. The total EMI SE value for the synthetic PVA/PANI/MWCNT/Fe3O4 was found at 9.2 and 10 GHz is 48 and 54 dB, respectively, exhibiting synergistic properties of the composites toward EMI shielding. The microwave absorption spectra indicate two absorption peaks in the region around 8 to 12 GHz, with the absorption reflection loss (RL) value of −20 dB at 10 GHz for the PVA/PANI/MWCNT/5% Fe3O4 nanocomposites. [ABSTRACT FROM AUTHOR]

Herein, a study on the dielectric properties of ZnO–P2O5–SeO2 glass ceramics containing varied contents of Ag2O is presented. Structural analysis of the samples by X‐ray diffraction, transmission electron microscopy, differential scanning calorimetry, Fourier transform infrared spectra, and optical absorption techniques indicated that the glasses are embedded with Ag3PO4, Ag2SeO3, and Zn3(PO4)2 anisotropic crystal phases along with Ag+ ions and Ag0 particles. Dielectric properties, ac conductivity (σac), and dielectric breakdown strength (DBS) are investigated as functions of Ag2O concentration. The results show the maximal concentration of Ag+ ions and Ag0 metallic particles in the sample containing 0.6 mol% of Ag2O. Dielectric parameters and (σac) increase with increasing Ag2O up to 0.6 mol%, while the DBS and electrical impedance decrease. The observed dipolar effects are quantitatively analyzed and possible dipoles are identified. Ionic contribution is predominant up to 0.6 mol% of Ag2O, beyond which the polaronic tunneling phenomenon prevails. These findings indicate that 0.6 mol% of Ag2O is the optimal concentration for using these glass ceramics as solid electrolytes in ionic batteries. Moreover, glass ceramics containing Ag2O beyond 0.6 mol% have exhibited larger polaronic conductivity, hence such glasses can be considered suitable candidates for electrodes in ionic batteries. [ABSTRACT FROM AUTHOR]

The proliferation of electromagnetic (EM) pollution is more rapid now and can be more outrageous in near future due to the exponential growth of the electronics industry. Strategy of using natural fibers for fabricating efficient EMI shielding materials is an environmentally benign solution for this serious peril. With this motivation, we are introducing novel e-textile derived from sustainable jute fabrics that are capable of suppressing and absorbing EM radiations in the frequency range 8.2–12.4 GHz (X-band). In the present work, jute fabrics were in-situ polymerized with pyrrole monomer. These conductive fabrics were then characterized and correlated for their structure, morphology, thermal stability, electrical conductivity, and EMI shielding capabilities. Moreover, this e-textile showcased excellent electrical conductivity of 1.160 S/cm and exhibited a maximum EMI shielding effectiveness value of −30.2 dB (>99.9% blockage) at 1 mm fabric thickness by a predominant absorption behavior with menial reflection or secondary pollution, which is highly beneficial for commercial applications. This is so far the first report of jute fabrics as e-textile with the highest shielding efficacy value reported, which makes them an ideal candidate for next generation of smart and wearable electronic textiles for futuristic applications such as robotics and artificial intelligence (AI).

Zn-doped and un-doped BCTO ceramics (Bi2/3Cu3−xZnxTi4O12, x = 0 and 0.05) were prepared by chemical route sintered at 1123 K for 8 h. The Phase formation of ceramics were confirmed by X-ray Diffraction. Their microstructural properties were examined through SEM, EDX, and TEM. The dielectric constant (ɛr) of BCTO ceramic was obtained higher than BCZTO-0.05 ceramics at 100 Hz and 470 K. The tangent loss (tan δ) value for Zn doped BCTO ceramics were found to be lower than undoped BCTO ceramics at 10 kHz and 310 K. The conductivity dependence of Bi2/3Cu3−xZnxTi4O12 ceramics (where x = 0, 0.05), with the inverse of temperature follows the Arhenius equation, with a major temperature range of 300–500 K. [ABSTRACT FROM AUTHOR]

A light weight electromagnetic interference (EMI) shielding and microwave absorbing composite films has been developed by loading varying weight content of graphitic carbon nitride (g-C3N4) nanosheets and polyaniline (PANI) into polyvinyl alcohol (PVA) matrix. The prepared PVA/PANI/g-C3N4 (1%, 3%, 5%) composites has been subjected to FTIR, X-Ray powder diffraction, SEM, Thermal studies, Dielectric studies and electromagnetic shielding effectiveness (EMI SE) analysis. The PVA/PANI/g-C3N4 (1%, 3%, 5%) composites was discovered to have improved electrical conductivity, dielectric loss, and dielectric constant. It is observed from the SEM images that the sheet layers of g-C3N4 are wrapped by the polymer matrix and the morphology to PVA/PANI composite in the g-C3N4 indicates homogeneous blending of PVA/PANI without any phase separation and has porous in it. The PANI/g-C3N4 fractured surfaces present are smooth but irregular in appearance indicating good compatibility between the PVA and PANI matrices. The dielectric properties was found to increase on increasing the concentration of the g-C3N4 nanofiller and reached a maximum of 9.8 × 106 at 1 MHz for 3% g-C3N4 in PVA/PANI. The incorporation of g-C3N4 into PVA/PANI enhanced the conductivity and the 5% g-C3N4 loaded composite film exhibited a conductivity value of 0.043 S/cm at 1 MHz. The PVA/PANI/g-C3N4 (1%, 3%, 5%) composites exhibited potential EMI SE values ranging from 24 to 35 dB at 8.6 GHz and from 42 to 63 dB at 12.4 GHz, for instance the PVA/PANI/g-C3N4 5% composite showed highest value of 63 dB at 12.4 GHz. The PVA/PANI/g-C3N4 5% exhibits the maximum highest reflection loss 8 GHz–12 GHz in which the higher absorption of −36 dB is observed at 10.3 GHz of the X-band region. [ABSTRACT FROM AUTHOR]

From the citrate gel auto-combustion method, spinal ferrite of Al-substituted Mg nanoferrites has been synthesized. Structural, optical, and electromagnetic behaviours were reported by XRD, UV–Vis, dielectric studies, and VSM, respectively. According to XRD analysis, the phase of the nanoferrites belongs to the FD3M space group and has a crystalline size of 14–25 nm. The lattice constant is found to be 7.841–8.296 Ao. The FTIR spectral bands appearing in the 600 & 400 cm−1 wavenumber regions indicate that the prepared sample has a tetrahedral (A site) and octahedral (B site) structure, respectively. In the Raman spectra, five active modes (A1g + Eg + 3Tg) were observed, which would be expected in the spinel ferrite system. The optical band gap energy was obtained from the UV–visible spectrum and found to be 3.43 to 3.49 eV. The effects of aluminium substitution on AC conductivity, impedance analysis, dielectric constant, and loss were investigated. The AC conductivity increased with applied frequency and temperature, whereas the dielectric constant and loss decreased, which phenomenon was explained by the Maxwell–Wagner polarization theory. Single semi-circle behaviour is observed in the impedance spectrum. [ABSTRACT FROM AUTHOR]

In the present work, we have synthesized rare-earth ion modified Bi4−xRExTi2Fe0.7Co0.3O12−δ (RE = Dy, Sm, La) multiferroic compounds by the conventional solid-state route. Analysis of X-ray diffraction by Rietveld refinement confirmed the formation of a polycrystalline orthorhombic phase. The morphological features revealed a non-uniform, randomly oriented, plate-like grain structure. The peaks evident in the Raman spectra closely corresponded to those of orthorhombic Aurivillius phases. Dielectric studies and impedance measurements were carried out. Asymmetric complex impedance spectra suggested the relaxation of charge carriers belonging to the non-Debye type and controlled by a thermally activated process. Temperature-dependent AC conductivity data showed a change of slope in the vicinity of the phase transition temperature of both magnetic and electrical coupling natures. Based on the universal law and its exponent nature, one can suppose that the conduction process is governed by a small polaron hopping mechanism but significant distortion of TiO6 octahedral. The doping of the A-sites with rare-earth element ions and changes in the concentrations of Fe and Co ions located on the B-sites manifested themselves in saturated magnetic hysteresis loops, indicating competitive interactions between ferroelectric and canted antiferromagnetic spins. The magnetic order in the samples is attributed to pair-wise interactions between adjacent Fe3+–O–Fe3+, Co2+/3+–O–Co3+/2+, and Co2+/3+–O–Fe3+ ions or Dzyaloshinskii–Moriya interactions among magnetic ions in the adjacent sub-lattices. As a result, enhanced magnetoelectric coefficients of 42.4 mV/cm-Oe, 30.3 mV/cm-Oe, and 21.6 mV/cm-Oe for Bi4−xDyxTi2Fe0.7Co0.3O12−δ (DBTFC), Bi4−xLaxTi2Fe0.7Co0.3O12−δ (LBTFC), and Bi4−xSmxTi2Fe0.7Co0.3O12−δ (SBTFC), respectively, have been obtained at lower magnetic fields (

Organic nonlinear optical single crystal of 2-aminopyridinium maleate (2APM) was grown using a slow evaporation method. The single crystal X-ray diffraction study reveals that the crystals possess to monoclinic system with acentric space group Pc. The Fourier Transform Infrared spectrum is used to identify the sample functional group. Lower cutoff wavelengths have been seen down to 342 nm and the direct optical band gap has been calculated to be 5.9 eV in this region of the spectrum. The microhardness of the 2APM sample was refined using a Vicker's microhardness tester under matching stress. DSC analysis was used to assess the crystal thermal stability. The 2APM crystal dielectric behavior was investigated over a range of frequencies. The Nd: YAG laser was utilized to create the second harmonic waveform. The 2APSS crystal emission spectrum was uncovered during a photoluminescence experiment. Third-order nonlinear susceptibility χ(3) = 5.741 x 10−8 of 2APM formed crystal was utilized to estimate the values for third-order NLO exploits. [ABSTRACT FROM AUTHOR]

The complex was prepared with preyssler polyoxoanion and transition metal (Mo), a cationic surfactant as a connector. It has tuneable physical and chemical potential which has been exploited to study novel properties. A new technique of shock wave impulses is also used on the Mo-PHP complex. Extensive use of cationic surfactants could impact accumulation in the environment set off the surfacing of bacterial resistance. Due to the electrostatic binding to bacterial surface, the hydrophobic parts of cationic surfactants tend to penetrate bacterial cell walls and may cause membrane lysis and bacteria death. The surfactant-supported and direct release of metal ions from P5W29Mo against bacterial resistance has been explained schematically. The dielectric study helps to understand the dissociation of cations that generate polarons and the hopping mechanism with neighbouring vacant atomic sites. Structural analysis confirms the formation of cationic surfactant incorporated polyoxoanion (Mo-PHP). A hexagonal shape-like structure for the PHP complex has been observed. The Mo-incorporated PHP complex was characterized using UV-visible (UV), Fourier Transforminfrared (IR), Raman spectra, scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD) techniques. [ABSTRACT FROM AUTHOR]

Zinc selenium phosphate glasses added with the traces of Au2O3 were prepared and heat-treated. XRD, TEM, DSC, FT-IR and optical absorption (OA) spectroscopy methods were used for the structural assessment of these samples. Later, different dielectric parameters viz., dielectric constant (ε′), electric moduli (M), impedance (Z) and a.c. conductivity (σac) were measured over wide regions of frequency (ω) and temperature (T) as functions of Au2O3 concentration. Dielectric breakdown strength (DBS) of these samples was also measured at ambient conditions. The characterization studies indicated that multiple crystal grains were entrenched in the residual amorphous phase of the samples. The X-ray diffraction studies revealed that the bulk glasses consisted of Au2(SeO3)3 crystal phase and Au0 metallic particles (MPs). As Au2O3 content was raised, the intensity of the XRD peak related to Au3+ crystal phase indicated a growing trend, whereas that of Au0 MPs showed a decreasing trend. The results of XPS studies revealed similar inferences. The FT-IR results pointed out an improved degree of augmentation of the glass network as the content of Au2O3 was increased. Optical absorption (OA) - spectra of the glasses indicated a broad absorption band in the spectral range of 500–600 nm due to the surface plasmon resonance (SPR) of Au0 MPs. The intensity of the band was observed to decrease as Au2O3 content was increased and indicated decreasing proportion of Au0 metallic particles in the samples. The dielectric parameters exhibited a decreasing trend, whereas the dielectric breakdown strength (DBS) and electrical impedance indicated a substantial hike due to the increasing concentration of Au2O3. Overall, the presence of Au2O3 caused a significant improvement in the insulating strength of the ZnO added SeO2-P2O5 glasses and hence such glasses may be considered as insulating layers in the display panel devices. [ABSTRACT FROM AUTHOR]