Overlapping Large Polaron Tunneling Research Articles

Study on nonlinear conduction of PEDOT:PSS conducting polymer

In the present study, solid film of poly (3,4-ethylenedioxythiophene):polystyrenesulfonate, (PEDOT:PSS) has been prepared by casting its aqueous solution at room temperature and are characterized by using X-ray diffraction and differential scanning calorimeter. The temperature-dependent behavior of the ac and dc conductivity of the PEDOT:PSS film has been investigated. The temperature dependence and scan rate dependence of J-V characteristic curves have been tested. The study of frequency dependence of ac conductivity in a wide range of temperature up to 443 K, indicates that the dominant conduction mechanism in PEDOT:PSS film is Overlapping-Large Polaron Tunneling (OLPT). The study of the electrical conduction with applied voltage shows a reversible negative differential resistance (NDR) through the turnover point (T.O.P) for Cu/PEDOT:PSS/Cu device. Threshold current density, Jth, and threshold voltage, Vth at T.O.P as well as NDR are strongly affected by ambient temperature up to 383K and scan rate up to 3V/sec. The turnover behavior has been explained according to a competition between high conduction due to schottky emission and NDR due to field-induced of electrical polarization in conduction paths.

Structural phase transition, vibrational analysis, ionic conductivity and conduction mechanism studies in an organic-inorganic hybrid crystal: [N(CH3)3H]2CdCl4

Hybrid organic-inorganic metal halides (HOMHs) present good application prospects in optoelectronics and photovoltaic as a result of their richness in physical properties and diverse structural assemblies. Herein, the organic-inorganic hybrid compound, [N(CH3)3H]2CdCl4 (1) is successfully synthesized by slow evaporation at room temperature. X-ray powder diffraction shows that 1 crystallizes in the orthorhombic system with the space group Pna21. The chemical composition of 1 is discussed by a STEM−EDS. Two-phase transitions at T1=253/263 ​K and T2=290/300 ​K are confirmed by the differential scanning calorimetry (DSC) curve. The measurements of the electrical properties are performed in the 10−1−107 ​Hz frequency range and 220−335 ​K temperature interval. The study on the charge transfer mechanism of 1 is done with the help of Elliott’s theory. The conduction mechanism in 1 is interpreted by different approaches: the correlated barrier hopping (CBH) model in phase I, the non-overlapping small polaron tunneling (NSPT) model in phase II, and the overlapping large polaron tunneling (OLPT) model in phase III.

Investigations of biodegradable polymer blend electrolytes based on Cornstarch: PVP: NH4Cl and its potential application in solid-state batteries

Incorporation of ammonium chloride (NH4Cl) with optimized Cornstarch: Poly vinyl pyrrolidone (80:20) polymer blend electrolytes were prepared by the technique of solution casting. XRD study reveals the incorporation of NH4Cl fully dissolved to make complexation to the polymer matrix. This complexation between polymer and salt was further confirmed by FTIR study by peak shifting and peak shape changing. Variation of asymmetry and symmetry stretching and vibration of cation (NH4+) were investigated by deconvoluted peak of FTIR in absorbance mode at O–H region and area of deconvoluted peaks in C–O region was changed by the increment of salt concentration in polymer blend electrolyte. It was used for the measurement of percentage of free ions and conduction ions. For 25 wt% NH4Cl-added polymer electrolyte system, there was 60.45% of free ions and also higher conductivity value of 1.53 × 10–6 S cm−1 at 303 K. The ion conduction in the polymer electrolyte is followed the overlapping large polaron tunnelling (OLPT) conduction model. From Arrhenius plot, conductivity of all the samples was linearly increased to follow the Arrhenius behaviour and low activation energy obtained was 0.151 eV for higher conducting sample. Dielectric studies confirmed the non-Debye nature and there was a existence of a shift in the relaxation peak towards the high frequency and thereby decrease in relaxation time.

Electric Transport and Dielectric Studies of CoFe2O4-BaFe12O19 Nanocomposite

Electric transport properties of cobalt ferrite and barium ferrite composite were studied in the frequency range of 1 Hz to 1 MHz with temperature varying from 100 to 500 °C. The composite with weight ratio 1:1 (CoFe2O4:BaFe12O19) was synthesized by chemical co-precipitation route. Rietveld refined X-ray diffraction analysis revealed pure phase formation of cobalt ferrite, barium ferrite and the prepared composite. For the prepared composite, dual phase refinement procedure was employed. Average crystallite size of CoFe2O4 and BaFe12O19 was observed as 19 nm and 51 nm respectively. The conduction and polarization mechanism in ferrites was explained on the basis of Maxwell–Wagner theory and Koop’s model which reflects the contribution of grain and grain boundaries present in the specimens. The conductivity analysis confirmed the presence of overlapping large polaron tunneling (OLPT) model for conduction.

Study of charge transfer mechanism and dielectric relaxation of all-inorganic perovskite CsSnCl3.

In the field of commercialization, lead-free metal halide perovskite materials are becoming more popular these days because of their prospective use in solar cells and also in other optoelectronic applications. In this paper, a non-toxic CsSnCl3 metal halide is successfully synthesized via the slow evaporation solution growth technique. Such systematic characterizations as differential scanning calorimetry (DSC) measurements, dielectric measurements, and variable-temperature structural analyses indicate that CsSnCl3 goes through a reversible phase transformation at T = 391/393 K from the monoclinic to the cubic system. Optical measurements of CsSnCl3 reveal a direct band-gap value of about 3.04 eV. The study of the charge transfer mechanism of CsSnCl3 is carried out based on Elliott's theory. The conduction mechanism in CsSnCl3 is interpreted through the following two approaches: the non-overlapping small polaron tunneling (NSPT) model (monoclinic phase) and the overlapping large polaron tunneling (OLPT) model (cubic phase). Moreover, the high dielectric constant of CsSnCl3 which is associated with a low dielectric loss makes it a possible candidate for energy harvesting devices.

Enhancing the electrical and dielectric properties of ZnO nanoparticles through Fe doping for electric storage applications

The present paper provides significant results about the impact of iron doping on the ZnO nanoparticles’ structural and electrical properties. Fe-doped ZnO (ZnO:Fe) nanoparticles with varying doping concentrations from 0 to 5% were effectively synthesized by a simple co-precipitation method. The X-ray diffraction (XRD) studies revealed that all compositions crystallize in the hexagonal wurtzite structure with the P63mc space group. They also proved the presence of a secondary phase accredited to ZnFe2O4 for ZnO:Fe 5% sample. Concerning the transmission electron microscopy, it demonstrated that the formed nanoparticles are spherical. The electrical properties were explored by complex impedance spectroscopy in the 40–107 Hz frequency range and 400–500 K temperature domains. The comparative Nyquist plots at fixed temperature 440 K suggested that the impedance value dropped with the augmentation of Fe doping concentration. Furthermore, the electrical conductivity and dielectric properties were explored as a function of frequency and temperature in the same range. The obtained results demonstrated that iron doping enhanced the AC conductivity at the same selected temperature 440 K. The analysis of the AC conductivity frequency dependence of the ZnO:Fe 1% sample was carried out by Jonscher’s universal power law and the conduction mechanism was interpreted by the overlapping-large polaron tunneling (OLPT) model. Both impedance and modulus analyses were found to display the contribution of grain and grain boundary to the electrical response of the ZnO:Fe 1% sample. Moreover, the dielectric characterization had affirmed that both dielectric constant and dielectric loss decrease with the increase in frequency and increase with the increase in temperature. These two parameters were found to augment with Fe doping. The observed properties had proven that Fe doped ZnO nanoparticles was very functional for the electric storage applications.

Electrical impedance spectroscopy study of unsubstituted palladium (II) phthalocyanine

A pressed pellet of unsubstituted palladium (II) phthalocyanine (PdPc) was synthesized and characterized by UV-Vis transmittance and impedance spectroscopy. Optical absorbance analysis revealed that upon increasing the concentration, the absorption at 630 nm became more intense, demonstrating strong aggregation at high concentrations. For the synthesized PdPc pellet, the absorbance decreased beyond 800 nm, and the direct band gap energy was 1.95 eV. The electric properties of the sample were studied for a range of frequency (40–107 Hz) and temperature (300–660 K) using complex impedance analysis. The activation energy and the relaxation time values for both time and frequency ranges were close to each other, suggesting that the electrical conduction and relaxation phenomena were controlled by the same type of charge carrier in the sample. Notably, the sample exhibited a semiconductor–metal transition at temperature TSM = 560 K. The AC-conductance was satisfactorily explained using the Jonscher universal power law. The electrical transport mechanism was dominated by the overlapping large polaron tunneling (OLPT) model. Furthermore, impedance spectroscopy analysis revealed a non-Debye-type relaxation. The Nyquist plot indicates the presence of grains and grain boundary effects. The results demonstrate that this material may be a promising candidate for photovoltaic applications.

(CH3)3N(CH2)2Br]2[CoBr4] halogenometallate complex: crystal structure, high-temperature reversible phase transition, electrical and optical properties

A new Co(II)-based organic-inorganic hybrid compound, [(CH3)3N(CH2)2Br]2[CoBr4], was synthesized by slow evaporation at room temperature. The compound was characterized by single crystal X-ray diffraction, thermal analysis, optic and dielectric measurements. [(CH3)3N(CH2)2Br]2[CoBr4] belongs to the monoclinic P21/c space group at 150K. Molecular structure of the compound consists of discrete [CoBr4]2− anions and (2-bromoethyl) trimethylammonium cations linked together via non-covalent interactions including C-H...Br hydrogen bonding and weak halogen…halogen interactions which lead to a three-dimensional supramolecular network. The thermal analysis reveals a reversible phase transition at 366/337 K upon heating/cooling respectively, which is giving rise to a thermal hysteresis of ~26 K. In addition, the UV/Vis optical spectrum indicates that the material has an indirect band gap of 3.7 eV which can be used in the application of the semiconductor materials. The electrical properties as a function of frequency and temperatures were studied and confirmed the phase transition showed in the thermal analysis. The equivalent circuit was determined to separate grain and grain boundaries response and determine the grain resistivity. The modulus studies confirm the presence of grain and grain boundaries. The AC conductivity was analyzed by Jonscher power law and showed that the conduction mechanisms are well described by the small polaron tunnel (SPT) and overlapping large polaron tunneling (OLPT) models in the phases I and II, respectively. The variation of σg, fp and σdc from the simulation of Nyquist diagram, Modulus and AC conductivity proves the transition in the DSC and allows to determinate the activation energies for the two phases. These results will provide positive clues to explore the semiconductor and electrical properties of hybrid halogenometallate complexes.

Proton conducting polymer electrolyte based on cornstarch, PVP, and NH4Br for energy storage applications

Proton conducting polymer blend electrolytes based on cornstarch and polyvinyl pyrrolidone (PVP) with ammonium bromide (NH4Br) were prepared by the technique of solution casting. Enhancement of amorphous nature by the addition of NH4Br has confirmed by XRD. In FTIR,by the addition of NH4Br salt in the optimized blend system, there occurs a change like altering the peak intensity, peak shape, and position. This reveals the appearance of complex formation between the polymer and salt. At 358 K, 30 wt.% of NH4Br added system shows the maximum conductivity (1.31 × 10−4 S cm−1). The conduction mechanism of higher conducting polymer blend electrolytes follows the quantum mechanical tunneling (QMT) at mid-frequency and overlapping large polaron tunneling (OLPT) at higher frequency. High dielectric constant and low relaxation time of ions in polymer chain are obtained for 30 wt.% of NH4Br added polymer blend electrolyte. From Wagner’s polarization technique, it is established that conduction present in the polymer electrolytes is predominately due to ions. Faradaic pseudo capacity behaviour has observed in higher conducting sample by cyclic voltammetry. The electrochemical cell has prepared by the higher conducting polymer electrolyte and the open circuit potential (OCP) of 1.24 V has achieved from prepared electrochemical cell.

AC conductivity and dielectric relaxation of chitosan/poly(vinyl alcohol) biopolymer polyblend

Polyblend samples of chitosan/poly(vinyl alcohol) (PVA) have been prepared using a casting technique. Scanning electron microscopy, Fourier transform infrared spectroscopy and thermogravimetric analysis measurements revealed that chitosan and PVA are compatible with each other. Alternate current (AC) conductivity and dielectric relaxation features of pure and polyblend samples are analysed in the frequency range of 0.1 Hz to 100 kHz covering a broad temperature range from room temperature to 423 K. Variation of AC conductivity, σAC, of pure and chitosan/PVA polyblend samples is found to be characterized by a plateau region at low frequency and high temperature, and this plateau region increases with increase in temperature. Based on the behaviour of the exponent s vs. temperature, AC conductivity dependence on frequency is found to be correlated with overlapping-large polaron tunnelling (OLPT) model. The polyblend samples showed an improvement in their dielectric properties compared to the pure materials. The dielectric constant, e′, of polyblend samples was increased by increasing the content of PVA. The dielectric dispersion was observed in the variation of e′ against frequency for all samples. The high values of e′ for all samples at high temperature and low frequency are attributed to space charge polarization. Also, loss tangent-frequency behaviour of pure chitosan, PVA and all polyblend samples showed two distinguished relaxation peaks with different values of activation energies. The first relaxation peak is termed as interfacial polarization or Maxwell–Wagner–Sillars polarization due to heterogeneity of the polyblend samples, whereas, the second relaxation peak is termed as δ-relaxation and α-relaxation, for pure chitosan and PVA, respectively.

A new (MOM) approach of the (OLPT) model application to the (AC) conductivity in ZnS chalcogenide material

In this work, we have proposed a theoretical investigation of the complicated Overlapping Large Polaron Tunneling (OLPT) conduction mechanism. In fact, in previous works, some approximations have been made in the aim of adopting the (OLPT) model to the experimental data. These approximations are not convincing and lead to reviewing the (OLPT) model.Thus, in order to avoid these disagreements between experimental and theoretical results, we have proposed a new “methodology” which has allowed us to explore in depth this mechanism of conduction not well investigated. Due to the existence of two variables: temperature and frequency, a fundamental step is to adopt a new approach to fit theoretical parameters to experimental data: the Advanced Second order Fitting (ASF). This approach allowed us to discover the existence of relevant term appearing in the expression of the trapping potential. The corresponding physical interpretation reveals an original and unexpected behavior. The modified (OLPT) model (MOM) proves in a categorical way the validity of certain approximations used without being adequately justified by the (OLPT) model. (MOM) highlights two competitive and spectacular phenomena: the thermal effect and the resonance phenomena. In this work, we have considered the example of ZnS: a chalcogenide presenting the (OLPT) conduction mechanism.

Summerfield scaling model and conduction processes defining the transport properties of silver substituted half doped (La–Ca) MnO3 ceramic

Conductivity spectra of La0.5Ca0.3Ag0.2MnO3 (LCAM) oxide have been investigated in the temperature range [80 K–680 K]. The studied system displays a semiconductor behavior over the explored temperature and frequency ranges. From direct current study, the transport of charge carries is assisted via disorder energy below θD/4. For the temperature range [θD/4- θD/2], the transport properties are governed by activation of Mott-variable range hopping (Mott-VRH) process. Beyond θD/2, the conduction phenomena are assisted through the thermally activation of the small polaron hopping (SPH) mechanism. At high frequencies, the conductivity spectra reveal a dispersive region. They are explained by the double Jonscher response. The latter side was characterized by the appearance of the overlapping-large-polaron-tunneling (OLPT), the correlated barrier hopping (CBH) and the non small polaron tunneling (NSPT) conduction processes. It is found that the calculated disorder energy is frequency independent. At elevated frequencies, the hopping energy is predicted to decrease with increasing frequency which can be related to the change in the Polarons radius. In the temperature range [80 K–220 K], the conductivity spectra follow double Jonscher law. Using the scaling model, the spectra merge into a single master curve, which confirmed the validity of the time temperature superposition principle (TTSP). A confident divergence from the Summerfield is noticed at high frequencies. It proves that the charge mobility is temperature dependant. The Summerfield correction scaling is effectuated by introducing a scaling positive parameter (α = 1.2). An excellent coalescence of conductivity spectra is observed.

Charge transport mechanism in BaFe12O19 and BaFe11CoO19

The conduction and charge transport mechanism of cobalt substituted barium hexaferrite (BaCoM) were studied by impendence spectroscopy at different temperatures and compared with BaM. Frequency dependent impedance spectra showed two distinct relaxations in BaM whereas a single relaxation peak was present in BaCoM. The relaxation frequencies were found to be temperature dependent. Scaling behaviour confirmed the dynamic conduction process is temperature independent and deviates from Debye type relaxation. Brick layer model has been employed to investigate the charge conduction through grain and grain boundaries. Arrhenius plot of conductivity showed two sharp transitions in three different temperature regime which indicates parallel conduction mechanism in the system. The frequency dependent conductivity was fitted with Jonscher’s power law at different temperatures. The variation in frequency exponent with temperature confirmed the evidence of three types of conduction process. Higher conductivity and different transition temperature was observed for BaCoM as compared to BaM. The conduction process was in accordance with overlapping-large polaron tunnelling model.

Temperature-dependent transport properties of micro and nano-sized zinc cobalt oxide (ZnCo2O4) and zinc manganese oxide (ZnMn2O4) particles synthesized by a hydrothermal route

In the present work, a hydrothermal method has been adopted to synthesize micro (~150 nm), and nano (~20 nm) particles of Zinc based, cobalt, and manganese oxide structures, i.e., ZnCo2O4 (ZCO) and ZnMn2O4 (ZMO). These structures have been examined by X-ray diffraction, Field-emission scanning electron microscopy with energy-dispersive X-ray spectroscopy, transmission electron microscopy, and Fourier transform infrared spectroscopy. The effect of different reducing agents and solvents have been ascertained on the morphological and the crystalline nature of the samples. The highly crystalline and micron-sized particle formation has been observed with the usage of NaBH4 as the reductant in the water solution, and a polycrystalline structure with nanosized particle formation has been found with NaOH as the reductant in the water and DMF solution. The electrical properties have been investigated between 100 Hz and 1 MHz by varying the temperature from 303 K to 513 K. The micro and nano sized particles of ZCO and ZMO have shown frequency dependence, thermally activated and relaxation-type dielectric behavior confirming the semiconducting nature. The variation of ac conductivity with frequency at different temperatures is according to Jonscher's power law for micro and nano sized particles of the ZCO and ZMO but supporting different conduction mechanisms. The conduction mechanism in microparticles and nano-particles is according to an overlapping-large polaron tunneling (OLPT) model, and the Non-overlapping small polaron tunneling (NSPT) model, respectively.

The sodium-ion battery: Study of alternative current conduction mechanisms on the Na3PO4 - Based solid electrolyte

Abstract Sodium-ion batteries have been dominating as a power source in digital cameras, laptop computers, mobile phones and electric/hybrid electric vehicles. This can be explained by their high life cycle and power density which differentiate them from other battery types. Sodium phosphate is considered among the favored solid electrolyte materials for the sodium-ion battery because of its high ionic conductivity. In this study, Na3PO4 was obtained using the classic ceramic method and characterized by X-ray powder diffraction patterns, infrared spectroscopy, differential scanning calorimetry (DSC) and electrical impedance. The Na3PO4 compound crystallized at room temperature in the tetragonal system with a P 4 ‾ 2 1 c space group. The morphology and composition of Na3PO4 were studied by a scanning transmission electron microscope coupled with the energy dispersive X-ray spectroscopy (STEM-EDS). The phase transition at T1 ≈ 603/605 K was confirmed by the differential scanning calorimetry (DSC). Infrared spectroscopy confirmed the presence of the (PO4)3− group and its vibrations. The electrical technique was measured in the 10–106 Hz frequency range and 540–700 K temperature intervals. The frequency dependence of alternative current conductivity was explained using Jonscher law. The alternative current electrical conduction in Na3PO4 was interpreted through several processes, which could be associated with two different models: the overlapping large polaron tunneling (OLPT) model in phase I and the non-overlapping small polaron tunneling (NSPT) model in phase II. The conduction mechanisms of Na3PO4 were explained by Elliott's theory and consequently the Elliott's parameters were calculated.

Impedance and ionic transport properties of proton-conducting electrolytes based on polyethylene oxide/methylcellulose blend polymers

Abstract Proton-conducting polymer electrolyte films were prepared by dissolving NH4I salt in polyethylene oxide/methylcellulose (PEO/MC) blend polymers using the solution cast technique. The semi-crystalline nature of the sample was identified from the X-ray diffraction (XRD) pattern. The surface morphology on the electrical conductivity was analyzed by scanning electron microscopy (SEM). The highest ionic conductivity of 7.62 × 10 − 5 S / c m was achieved at room temperature for the sample containing 30 wt. % of NH4I. The temperature dependence of the Jonscher's exponent shows that the conduction mechanism can be well represented by the overlapping large polaron tunneling (OLPT) model. The electrical conductivity enhancement was analyzed by the Rice and Roth model, which showed that the increase in the salt concentration caused an increment in the mobility and the diffusion coefficient of the ions. For all prepared samples, the highest value of conductivity was associated with the minimum value of activation energy. The dielectric data were analyzed for the highest ionic conducting sample at various temperatures to clarify an important factor of the ion conduction. The non-Debye behavior of the samples can be expressed from the electric modulus formalism and the dielectric properties of the electrolytes that have been proven by the incomplete semicircular arc of the Argand plots.

Structural, electrical, and leakage-current characteristics of double perovskite: Sm2CoMnO6

Double perovskite compound Sm2CoMnO6 was prepared by a high-temperature solid-state reaction route. The monoclinic structure of the compound was obtained by the X-ray structural analysis. The microstructure analysis reveals that there is an almost homogeneous distribution of grains with small voids. The detailed studies of dielectric and electrical properties, carried out in the frequency range of (1 kHz–1 MHz) at different temperatures (25–500 °C), have provided many interesting features of the material. The frequency dependence of dielectric parameters is described on the basis of Maxwell–Wagner model. In the study of temperature dependent dielectric parameters, an observed dielectric anomaly is considered as the ferroelectric-paraelectric phase transition. The complex impedance study (Nyquist plot) exhibits the existence of only grain effect which is represented by a single semicircle (RQC). The existence of the relaxation mechanism of the material is of non-Debye type that is established from the depression angle. In Nyquist plots both negative temperature coefficient of resistance (NTCR) and positive temperature of coefficient of resistance (PTCR) characteristics are observed in the compound. The frequency dependence of conductivity is analyzed by Jonscher’s power law which suggests that the existence of overlapping large polaron tunneling (OLPT) and correlated barrier hopping (CBH) conduction phenomena in the material. The temperature variation of leakage-current characteristics has been analyzed. The low leakage-current density is observed from the J–E characteristic curves.

Effect of PEG as a plasticizer on the electrical and optical properties of polymer blend electrolyte MC-CH-LiBF4 based films

Plasticized polymer blend electrolyte films based on methylcellulose (MC), chitosan (CH), lithium tetrafluoroborate (LiBF4), and polyethylene glycol (PEG) as a plasticizer were prepared and investigated. The effect of different concentrations of PEG was studied using AC impedance spectroscopy, and UV–Visible spectroscopy. The electrical and optical properties of polymer electrolytes have been improved upon addition of PEG. The DC conductivity was evaluated from the bulk resistance achieved from Nyquist impedance plots. Results from temperature studies reveal that all samples comply with the Arrhenius formula in the investigated temperature range. The sample with 10 wt% of PEG exhibits the highest ionic conductivity of 2.12×10-5S/cm with the minimum activation energy of 0.528eV at ambient temperature. The lowest relaxation time for highest ion conductive sample indicates the faster ion dynamics. The frequency-dependence AC conductivity was found to follows the Jonscher’s power law at various temperatures, and the conduction mechanism for this system followed the overlapping large polaron tunneling (OLPT) model. The increase in absorption and a decrease in optical band-gap in the UV region was confined by UV–Visible spectroscopy.

Effect of scandium substitution on magnetic and transport properties of the M-type barium hexaferrites

Polycrystalline M-type barium hexaferrite compounds with scandium doping BaFe12-xScxO19 (0 ≤ x ≤ 2.5) were prepared by the solid state route. Room temperature neutron diffraction measurements show that the prepared samples are in single phase and exhibit a ferrimagnetic structure at room temperature. Temperature and field dependent magnetization study shows that due to doping of scandium, TC is lowered from 696 K in the undoped compound to 428 K for x = 2.5. The transport properties were investigated by ac conductivity measurements. Our results indicate that the temperature dependence of dc conductivity for x = 2.5 does not follow Arrhenius behaviour but rather closely follows the Mott variable range hopping mechanism (VRH) of polarons. For the parent compound and with for Sc doping x = 1.5, the conductivity is found to be due to overlapping large polaron tunnelling (OLPT).

Cd-doping effect on morphologic, structural, magnetic and electrical properties of Ni0.6-xCdxMg0.4Fe2O4 spinel ferrite (0 ≤ x ≤ 0.4)

The effect of Cd-doping on physical properties of Ni0.6-xCdxMg0.4Fe2O4 spinel ferrite has been investigated. Scanning electron spectroscopy (SEM) confirms the formation of grain and grain boundaries in these samples and the presence of all chemical elements introduced was confirmed by EDS. The X-ray analyses indicate that all the compounds have the cubic structure with Fd3¯m space group, cell parameter increase which Cd content. A ferromagnetic state at room temperature for all compounds is detected by a magnetization measurement of hysteresis loops. We note that the saturation magnetization increases with Cd content, however, the remnant magnetization, and the corrective field decreases. DC electrical conductivity analysis shows a semiconductor behavior for all sample. In addition, non-overlapping small polaron tunneling (NSPT) and the overlapping large polaron tunneling (OLPT) are the dominants conductions mechanisms in our samples.