AC Conductivity Behavior Research Articles

Optical, AC conductivity and antibacterial activity enhancement of chitosan-silver nanocomposites for optoelectronic and biomedical applications

This study is aimed to prepare and investigate the optical, electrical and antibacterial activity of the environmentally friendly (green) chitosan (Cs)/silver nanocomposites. TEM demonstrated that AgNPs have a spherical shape with particle size ranged from 3 nm to 25 nm. UV analysis spectra of Cs and Cs/Ag nanocomposites showed that, increasing the content of AgNPs led to a noticeable increase in the values of Urbach energy (E U ) and a dramatic decrease in both the indirect (E ig ) and direct (E dg ) optical bandgap energies. It is found that (E ig ) and (E dg ) are decreased from (4.72/5.31 eV) to (2.47/4.19 eV). The formation of the AgNPs is verified by the existence of surface plasmon resonance (SPR) peak at ∼ (421–450) nm. Wemple-DiDomenico and Sellmeier oscillator models are employed and displayed a clear enrichment in the dispersion energy (E d ) and oscillator energy (E 0) as well as the linear and nonlinear optical parameters of Cs. It is observed that the linear (χ(1)) and nonlinear (χ(3) and n2) parameters are enhanced from 0.083, 0.868 × 10−14 and 1.584 × 10−12 to 0.153, 9.762 × 10−14 and 4.088 × 10−12. The novel results in our study nominate Cs/Ag nanocomposites for applications in linear/nonlinear optical devices. AC conductivity behavior of Cs and Cs/Ag nanocomposites is analyzed based on Jonscher’s law and the analysis showed that the overlapping large polaron tunneling (OLPT) is the dominant conduction mechanism for our samples. It is clear that the values of dielectric constant (ε′) of Cs and Cs/Ag nanocomposites are higher confirming the presence of interface polarization (IP) relaxation. Moreover, it is found that the antibacterial activity of Cs against Gram-negative (P. aeruginosa) and Gram-positive (B. thuringiensis) bacteria is found to be enhanced with increasing the content of Ag NPs. These results suggested that Cs/Ag nanocomposites will be good source for preparing bio-nanocomposites for use in many biomedical and industrial applications.

Investigating the dielectric and ferromagnetic behaviour of Ni and Co dual doped ZnO for diluted magnetic semiconductor

Herein, Ni/Co co-doped ZnO nanoparticles (NPs) were successfully prepared via chemical co-precipitation process. The structural, purity and crystallite size of as-prepared particles were confirmed by using x-ray diffraction (XRD). The results revealed the hexagonal wurtzite structure of ZnO without any impurity phase of as-prepared samples. The crystallite size decreased from 34.9 to 9.6 nm, whereas lattice strain reduced to 0.00086. The change in crystallite size, lattice parameters, strains and dislocation density further indicates the successful incorporation of dopants in ZnO host lattice. The dielectric properties, ac conductivity, and magnetic behaviour were steadily examined. The dielectric constant has been found to be 1070 with 5wt% at low frequency and become constant at higher frequency. It was revealed that dopant additions lead to attain high dielectric constant and low loss possibly attributed to interface polarization, and dipole polarization due to oxygen vacancy defects. M-H measurement observed that ferromagnetism at room temperature pure and doped ZnO samples. The ferromagnetic behaviour of pure ZnO NPs with Ms = 0.17 emu g−1, Mr = 0.11 emu g−1 and Hc = 67 which was increased to Ms = 0.85 emu g−1 and Mr = 0.65 emu/g for 5wt% Co. This improvement with increasing Co concentration indicates that oxygen defects may stabilize the ferromagnetic order. These interesting features encouraging to use this material for ultrahigh dielectric materials and spintronics.

Dielectric, thermal and optical properties of PVDF-based (LaFeO3)0.5 (BaTiO3)0.5 perovskite composite films for advanced technological applications

(1-x)PVDF/(x)LFO-BTO composite films with weight percentages (x = 0, 0.05, 0.1 and 0.15) were prepared by solution casting method. Phase identification was carried out using the X-ray diffraction (XRD) technique revealing different phases (α, β & γ) of PVDF. FTIR results confirmed the presence of different vibrational modes and phases including PVDF phases. AFM and SEM were used to investigate the surface & morphological analysis, the results showed that the surface roughness increased with the concentration of LFO-BTO into PVDF films. From optical absorption spectra, the direct band gap and indirect band gap energies of the PVDF/LFO-BTO were evaluated by incorporating Tauc's relation. The composites experienced a reduction in band gap upon the addition of 0 - 15 wt% of LFO-BTO with an increasing trend in Urbach's energy. The dielectric investigations revealed elevated dielectric constant values across all composites at lower frequency ranges, attributed to interfacial polarization. Specifically, the dielectric constant of 15 % wt of LFO-BTO was found to be much higher (6 times more than the pristine PVDF). Additionally, the dielectric loss was suppressed with increasing filler concentration within the frequency range of 1 KHz to 1 MHz. Impedance spectroscopy analysis depicted a distinctive semi-circular pattern that was linked to the underlying conduction mechanism. The behaviour of ac-conductivity revealed the conduction process following the Nyquist plot. DTA-TGA analysis showed a notable improvement in thermal stability with increasing concentration in the PVDF matrix.

Strong magnetoelectric coupling in novel Na0.5Bi0.5TiO3–BaFe12-2xCoxTixO19 multiferroic composite

Multiferroic composites of sol-gel synthesized Sodium Bismuth Titanate (Na0.5Bi0.5TiO3) and Co–Ti substituted Barium Hexaferrite (BaFe12-2xCoxTixO19; x = 0.0, 0.5, 1.0, 1.5 and 2.0) in the ratio 3:1 was synthesized through ceramic route. Successful formation of R3c rhombohedral and P63/mmc hexagonal phases corresponding to Na0.5Bi0.5TiO3 and BaFe12-2xCoxTixO19 respectively was confirmed from the XRD and Rietveld refinement pattern. The frequency and temperature dependence of dielectric constant and loss of the composite systems exhibited typical dispersion behaviour which could be understood using the Maxwell-Wagner model. Substituted samples showed enhanced dielectric behaviour where dielectric constant was observed to increase while loss tangent decreased. Using the Universal Jonscher's Power law (JPL), conductivition mechanisms of the composite systems were studied from the ac conductivity behaviour which revealed that the x = 0.0 sample followed Non-overlapping Small Polaron Tunnelling (NSPT) model while the remaining samples followed the Correlated Barrier Hopping (CBH) model. The complex impedance and Nyquist plot analysis showed the enhancement of resistive property in the x≠0 systems. Magnetic hysteresis loop measurements were conducted, and the associated parameters were determined with the assistance of the Law of Approach to Saturation (LAS). Favourable reduction in the magnetic anisotropy was observed indicating the disturbance of magnetic spin structure in the hexaferrite phase. The P-E loops established the novel room temperature multiferroic nature of the composite systems. Significant magnetoelectric coupling was detected at room temperature in all samples, with the x = 0.5 sample exhibiting the highest value of approximately 59.81 mV/cmOe. These desirable properties suggest that the composites may find future device applications as in magnetically tunable energy harvesting devices and self-powered magnetoelectric sensors in the future.

Scaling behavior of AC conductivity and modulus spectra of K2NiO4-type Sr2TiO4

Scaling behavior of AC conductivity and modulus spectra of K2NiO4-type Sr2TiO4

AC conductivity and dielectric relaxation behavior of lamellar benzyltrimethylammonium/V2O5 nanocomposite

Lamellar benzyltrimethylammonium/V2O5 nanocomposite has been prepared hydrothermally. Electrical and dielectric properties as a function of temperature and frequency of the nanocomposite were reported. The decrease in Z′ with increasing temperatures indicates the existence of a negative temperature resistance coefficient (NTCR) characteristic of the semiconductor material. For T > 432 K, the values of the exponents decrease with increasing temperature indicating that the CBH model is the likely mechanism. When T < 432 K, the NSPT model is an adequate mechanism to characterize electrical conduction. Variation of log(σdc) versus 103/T reveals a rupture around 432 K and the average activation energy values are of the order of 0.240 and 0.085 eV. It has been found that the dielectric constant and the dielectric loss decrease when frequency increases which is explained by the hopping of electrons between V4+/V5+. Moreover, the presence of non-Debye type of relaxation was detected by the complex modulus analysis.

Structural and electrical characteristics of manganese modified BaTiO3 ceramic

The material Ba(Ti0.5Mn0.5)O3 synthesized through the conventional solid-state reaction method has hexagonal structure free from any impurity phase. The complex dielectric dispersion, temperature and frequency-dependent dielectric, impedance, AC conductivity, and leakage behavior of the sample are studied. The impedance study of the material encloses non-Debye type relaxation, negative temperature coefficient of resistance nature and the grain and grain boundary effects. The ferroelectric to paraelectric phase transition occurs at T C ∼ 270 °C. The dielectric constant and loss-tangent values are found to be less as compared to that of the parent barium titanate sample. R g < R gb, that is, grain boundary has greater opposition than the grain region. The material follows correlated barrier hopping model. The carrier transport process through AC conductivity study obeys the Jonscher’s power law and the Arrhenius relation while varying with the frequency and temperature.

Understanding charge transport and dielectric relaxation properties in lead-free Cs2ZrCl6 nanoparticles.

In the exploration of perovskite materials devoid of lead and appropriate for capturing solar energy, a recent finding has surfaced concerning Cs2ZrCl6. This compound has attracted interest as a potential candidate, displaying advantageous optical and electrical features, coupled with remarkable durability under environmental stresses. This research outlines the effective production of non-toxic metal halide nanoparticles of Cs2ZrCl6 using the gradual cooling technique. Thorough examinations have been conducted to explore the structural, optical, and dielectric traits. Over the frequency range of 101-106 Hz, the dielectric constant, loss factor, electric modulus, and electrical conductivity of Cs2ZrCl6 exhibit a strong dependence on temperature. The Nyquist plot confirms the distinct contributions of grains and grain boundaries to the total impedance. In the high-frequency region, the dielectric constant tends to increase with temperature. In accordance with the modified Kohlrausch-Williams-Watts (KWW) equation, an asymmetric nature corresponding to the non-Debye type is observed in the electric modulus spectra at different temperatures. Furthermore, the imaginary part of the electric modulus spectrum shifts from the non-Debye type towards the Debye type with increasing temperature, despite not obtaining an exact Debye response. The frequency-dependent behavior of AC conductivity has been modeled using Joncher's universal law. The conduction mechanism within the Cs2ZrCl6 compound is attributed to the small polaron tunneling model (NSPT). Furthermore, Cs2ZrCl6 has the potential to function as an energy harvesting device due to its elevated dielectric constant combined with minimal dielectric loss.

Morphological, structural, optical and dielectric analysis of Cs2TiBr6 perovskite nanoparticles.

In the pursuit of lead-free perovskite materials suitable for harnessing solar energy, a recent discovery has emerged regarding Cs2TiBr6. This compound has garnered attention as a prospective candidate, exhibiting favorable optical and electrical characteristics alongside exceptional resilience when subjected to environmental strains. This study details the successful synthesis of non-hazardous metal halide nanoparticles of Cs2TiBr6via the slow cooling method. Comprehensive investigations into the structural, optical, and dielectric characteristics have been undertaken. The temperature sensitivity of various electrical properties, including the dielectric constant, loss factor, electric modulus, and AC/DC conductivity, is evident in this perovskite material. This phenomenon is observed across a frequency range of 1 to 107 Hz. Furthermore, examination of the Nyquist plot highlights the distinctive contributions of both grain and grain boundaries to the overall impedance characteristics. In the high-frequency range, it is observed that the dielectric constant exhibits an upward trend as the temperature rises. Examination of the adapted Cole-Cole plot unveils that both space charge and free charge conductivity escalate with increasing temperature, while concurrently, the relaxation time experiences a reduction with the temperature's ascent. We observed an asymmetrical pattern in the electric modulus spectra at varying temperatures using a modified Kohlrausch-Williams-Watts equation. This asymmetry is consistent with the inherent non-Debye nature of perovskite materials. Additionally, as the temperature increases, we note a shift in the imaginary component of the electric modulus spectra, transitioning from a non-Debye character towards a semi-Debye nature, though it does not achieve a strictly Debye-type response. This transformation indicates the semiconducting properties of the material. We elucidate the AC conductivity behavior in Cs2TiBr6 by employing the non-overlapping small-polaron tunneling (NSPT) mechanism as the basis. The activation energy, as determined from both the modulus spectra and DC conductivity, aligns closely, providing robust evidence for the congruence between the relaxation dynamics and the conduction mechanism. In addition to these attributes, Cs2TiBr6 exhibits a substantial dielectric constant coupled with negligible dielectric loss, thus establishing its potential suitability for energy harvesting devices.

Electrospun Microstructured Biopolymer Fibers Containing the Self-Assembled Boc–Phe–Ile Dipeptide: Dielectric and Energy Harvesting Properties

Hybrid biomaterials were engineered using the electrospinning technique, incorporating the dipeptide Boc–L-phenylalanyl–L-isoleucine into microfibers composed of biocompatible polymers. The examination by scanning electron microscopy affirmed the morphology of the microfibers, exhibiting diameters ranging between 0.9 and 1.8 µm. The dipeptide self-assembles into spheres with a hydrodynamic size between 0.18 and 1.26 µm. The dielectric properties of these microfibers were characterized through impedance spectroscopy where variations in both temperature and frequency were systematically studied. The investigation revealed a noteworthy rise in the dielectric constant and AC electric conductivity with increasing temperature, attributable to augmented charge mobility within the material. The successful integration of the dipeptide was substantiated through the observation of Maxwell–Wagner interfacial polarization, affirming the uniform dispersion within the microfibers. In-depth insights into electric permittivity and activation energies were garnered using the Havriliak–Negami model and the AC conductivity behavior. Very importantly, these engineered fibers exhibited pronounced pyroelectric and piezoelectric responses, with Boc–Phe–Ile@PLLA microfibers standing out with the highest piezoelectric coefficient, calculated to be 56 pC/N. These discoveries help us understand how dipeptide nanostructures embedded into electrospun nano/microfibers can greatly affect their pyroelectric and piezoelectric properties. They also point out that polymer fibers could be used as highly efficient piezoelectric energy harvesters, with promising applications in portable and wearable devices.

Dual role of CoO and electron beam irradiation in enhancement the transport properties of borate glasses

The synthesis of lithium borate cadmium glasses doped with cobalt oxide (CoO) (LiBCdCo) was achieved using the traditional melt-quench process. The chemical composition of the glasses was determined to be 12 % Li2O – 5 % CdO – (83-z)% B2O3, where z represents the mol% of CoO and ranges from 0.0 to 2. Various experimental approaches, such as X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), Raman spectroscopy, FTIR and electrical measurements, were employed to investigate the physical, structural, and electrical properties. XRD patterns obtained from the manufactured glass specimens revealed their amorphous nature. The EDX analysis provides insight into the exact chemical composition of the materials in their prepared form. Raman spectroscopy and FTIR analysis have been employed to verify the disparity in the chemical bonds present in lithium borate cadmium glasses, both in their undoped state and when doped with 2 % CoO. The study observed a decrease in density and oxygen packing density as the molar ratios of the modifier oxides in the produced glasses increased. The present study investigates the electrical conductivity and dielectric properties of the glass samples manufactured, focusing on the influence of electron beam irradiation (E.B.). The investigation revealed that the samples exhibited greater effects when exposed to higher doses (100 kGy) of electron beam irradiation. This can be attributed to the increased occurrence of defects, specifically the formation of non-bridging oxygen species (NBOs). The ac-conductivity measurements indicate that the correlated barrier hopping (CBH) mechanism is the most suitable explanation for the ac-conduction behavior observed. This mechanism involves the electron conduction in the CoO-doped glass samples through the hopping of electrons between relaxation sites. This conduction process is facilitated by the conversion of BO3 units into BO4 units and the reduction of cobalt ions from Co+2 to Co+3.

A comprehensive study on the influence of Mg doping on structural, AC conductivity, and dielectric behavior of ZnONPs

In this research magnesium (Mg) doped zinc oxide nanoparticles (Zn1-x MgxO, where x = 0 for pure ZnO) were synthesized using a simple chemical route. Their structure and morphology was characterized using different methods, such as X-ray diffraction, scanning electron microscopy, Fourier Transform spectroscopy, photoluminescence. Nanoparticles (NPs) were synthesized and analyzed for their structure, shape, chemical content, and optical and dielectric activity with Zn1-x MgxO (where x = 5,15,50 wt%). The crystalline, hexagonal ZnO was verified by X-ray diffraction, with an average grain size of 45 nm for ZnO and 28 nm for Mg doping and a more interplane spacing that ranges from 2.9 nm to 18 nm. In the nanoscale domain, with a hexagonal crystalline shape between 30 and 80 nm, Zn1-x MgxO were analyzed in scanning electron microscopy (SEM) pictures. Transmittance rises with doping, as shown by optical characterization, and UV–vis spectroscopy reveals low absorbance in the visible area. Absorption values drop dramatically for all samples in the UV region, and when magnesium content rises, the absorption peak moves to shorter wavelengths. As the Mg content increased from 5 % to 50 %, the optical absorption spectra of ZnO switched to red. The UV emission peak in PL spectra was seen between 389 and 700 nm. It revealed that up to 50 % Mg doping, the strength of the emission bands at 405 and 525 nm decreases. According to fluorescence emission, zinc oxide has interaction with porphyrin, which results in a new peak at 389 nm. This 389 nm peak is thus specific to ZnO and Zn1-x MgxO nanoparticles as a result of the electron transport between the two materials. The Zn1-x MgxO samples show low dielectric losses and high dielectric constants in the middle and high-frequency ranges. The Mg doping at 5 % concentration is particularly intriguing since it shows enormous dielectric constant across a broad frequency range. At low frequencies, all the samples suffer from a significant loss factor. In the high-frequency range, it stabilizes.

Optical and temperature-dependent electrical and dielectric properties of ultrasound-synthesized CdS quantum dots

CdS quantum dots (QDs) were synthesized by the ultrasound-assisted chemical precipitation technique. The structure analysis revealed the presence of bi-structural cubic and hexagonal phases with an average crystallite size of 3 nm. The N2-adsorption isotherm exhibited the evolution of meso-/macro-porous interfaces with a pore size of 7.56 nm and a surface area of 44.41 m2·g−1. The improvement of the quantum size effect in CdS QDs resulted in the increase of optical bandgap to 2.52 eV compared with the corresponding bulk phase. However, the analysis of long-tail states absorption revealed a very small Urbach energy of about 76 meV compared with CdS QDs prepared by other techniques. The as-synthesized CdS QDs revealed high room-temperature DC conductivity of 2.56 × 10–6 Ω−1 · m−1 and very small activation energy of 268 meV facilitating tunnelling of the thermionically excited carrier through the high bandgap of CdS QDs. The frequency-dependent behavior of AC conductivity (σ AC) and dielectric constant (ε r) of CdS QDs were investigated at different temperatures in the range from 303 K to 453 K. It was observed that both σ AC and ε r were improved with increasing temperature up to 363 K followed by a sudden decrease at higher temperatures.

Sonochemical-assisted preparation of mesoporous ZnS quantum dots: Optical, electrical, and temperature-dependent dielectric characteristics

Mesoporous ZnS quantum dots (QDs) were prepared by the sonochemical technique that indicated bi-structural cubic-hexagonal phases with an average particle size of 2.5 nm, a pore size of 4 nm, and 28.85 m2 g−1 surface area. ZnS QDs exhibited a high bandgap of 3.85 eV with a large Urbach energy of 280 meV. The presence of localized defects was verified by the photoluminescence emission that was ascribed to the recombination of trapped carriers in shallow and deep trapping states with photogenerated holes. ZnS QDs revealed a high DC conductivity of 5.37 × 10−6 Ω−1 m−1 and a small activation energy of 248 meV that facilitated the tunnelling of thermionically excited carriers. The frequency-dependent behavior of AC conductivity (σAC), dielectric constant (εr), and dielectric loss (ε′) was examined at various temperatures. It was observed that both σAC, εr, ε′ were enhanced with increasing temperature up to 333 K followed by a gradual decrease at higher temperatures.

Studies on properties of green synthesised CuO/ZnO nano particle/nano rod composites in PVA matrix

In this research article, we have investigated the structural, microstructural, optical and electrical properties of CuO/ZnO nanoparticle/nanorod composites in PVA matrix using a facile two-step method via the sol-gel technique. In this report, we have synthesized four samples as: (i) pure PVA (ii) CuO/PVA (iii) ZnO/PVA and CuO/ZnO/PVA. The structural properties of all the samples have been understood by carrying out X-ray diffraction measurements, which confirm the crystalline properties of CuO, ZnO metal oxides in PVA matrix. The microstructural properties of all the samples have been analyzed by Field Emission Scanning Electron Microscopy (FESEM) and Elemental Compositions in the samples have been identified by Energy Dispersive X-ray analysis (EDAX). The optical properties of all the samples have been analyzed using UV–visible spectroscopy. The electrical properties, such as dielectric behavior, AC conductivity and impedance behavior of all the samples have been characterized by an LCR meter at room temperature.

Mixed ionic-electronic transport in Na2O doped glassy electrolytes: Promising candidate for new generation sodium ion battery electrolytes

In the present communication, newly developed glassy electrolytes, Na2O–ZnO–CdO, have been considered to discuss their electrical transport behavior at ambient temperature. The AC conductivity and relaxation behavior of them have been studied in the light of Almond-West formalism. The electrical conductivity (mixed conduction) is found to be a function of frequency as well as temperature. In the low-frequency range, it shows a flat conductivity owing to the diffusional motion of Na+ ions, whereas at high frequency, the conductivity shows dispersion. The DC conductivity ( σ dc ) and hopping frequency have been computed from the best fitted plots of experimental data. The AC conductivity at different concentrations and a constant temperature has been reported. The variation in the conductivity data with reciprocal temperatures indicates the dynamical behavior of charge carriers via hopping conduction in sodium oxide glassy systems. Mixed conduction in the present system may be dominated by polaron hopping in the samples with a lower Na2O content with a percolation type of motion of the electron/polaron. On the other hand, three-dimensional Na+ motion is the dominating charge carrier for the samples with a higher Na2O content. A negligible small difference in pathways in the I–V characteristics in both the directions should make the present system a promising candidate for the new generation battery electrolyte.

AC conductivity and dielectric behaviour of polypyrrole – Holmium oxide composites

Polypyrrole/holmium oxide composites were prepared by in situ polymerization technique with ammonium persulphate as an oxidizer. Polypyrrole and PPy/Ho2O3composites were correlated in varying compositions viz. (10, 20, 30 40 and 50 wt%) of Ho2O3 in polypyrrole. As prepared composites were characterized by FESEM (Field Emission Scanning Electron Microscopy), EDX (Energy Dispersive X-ray Spectroscopy), XRD (X-ray Diffraction), FTIR (Fourier Transform Infrared Spectroscopy), AC conductivity and dielectric behavior of the composites were carried out by using Hioki model, computer confederated LCR meter accompanied by frequency scale ranging from 50 Hz to 1 MHz. Conductivity of the samples was observed to increase with increasing wt %. The change in dielectric constant of the polypyrrole composites with the applied frequency can be explained using Maxwell-Wagner polarization . Dielectric tangent loss curves can be attributed due to Rezlescu model.

AC conductivity and dielectric behavior of polyaniline –Neodymium oxide composites

Polyaniline-neodymium oxide (PNdO) composites were created using the chemical polymerization process with ammonium persulphate as oxidizing agent. Polyaniline (PANI) and PNdO composites were prepared in various compositions viz. (10, 20, 30, 40 and 50 wt%) of Nd2O3 in polyaniline. As synthesized composites were characterized by X-ray diffraction (XRD) studies proved the presence of Nd2O3 particles in PANI matrix., AC conductivity and dielectric loss of the composites was carried out in the frequency range from 50 Hz − 1 M Hz. AC conductivity of the composites exhibited decreased values of conductivities compared to PANI. Cole-Cole plots inferred single relaxation occurring inside PANI and the composites. Dielectric tangent loss curves exhibited single peak and can be explained using Rezlescu model.

Studies on the electrical properties of polyaniline with cadmium oxide nanocomposites

In situ polymerization method was used to prepare cadmium oxide nanoparticles (NPs) with polyaniline nanocomposites, by varying different weight percentages of cadmium oxide NPs, and the oxidizing agent as ammonium per sulfate as starting materials. The AC and DC conductivity behavior of PANI with CdO nanocomposites has been studied as a function of frequency and temperature. The XRD and SEM techniques were used to explore how the establishment of PANI and its nanocomposites impacts the structural and morphological properties of the materials.The structure of CdO NPs was found to be cubic phase confirmed from XRD. The electrical conductivities, DC conductivity of polyaniline and its nanocomposites were measured at 27 to 180°Celsius. According to the AC conductivity frequency variation, CdO NPs concentration increases along with AC conductivity in the low-frequency zone.

Ac conductivity and modulus behavior of K0.12Na0.54Ag0.34Nb4AsO13 compound

Some physical properties of K0.12Na0.54Ag0.34Nb4AsO13 powder, synthesized visa a solid-state reaction at 800 °C, are discussed in this study. The vibrational analysis verifies the existence of the AsO43− and NbO67− functional groups. The X-ray powder diffraction pattern and Rietveld refinement confirm the formation of a pure phase that crystallizes in an orthorhombic system with a Cmcm space group. The structure and chemical composition of the compound are studied using the Scanning Electron Microscopy and the Energy Dispersive Spectroscopy. Complex impedance spectroscopy is used to examine the electrical conductivity, dielectric properties and relaxation behavior of the aforementioned compound at different temperatures and across the 0.01 kHz–13 MHz frequency range. The correlation between K0.12Na0.54Ag0.34Nb4AsO13's crystalline structure and its ionic conductivity is also studied.