Nano Ferrites Research Articles

Investigation of dielectric, electrical and optical properties of copper substituted Mn-Zn nanoferrites

Transition metal such as Copper substituted Mn-Zn magnetic nano ferrite with general formula Mn0.5Zn0.5CuxFe2−xO4 (x = 0.0, 0.1, 0.2, and 0.3) were fabricated by solution combustion method and expose how significant properties of the samples are modified accordingly by dopant concentration. By FTIR spectroscopy various functional group present in Mn-Zn ferrites is studied. The optical plots revealed bandgap energy reduced from 2.42 to 1.82 eV although the electrical study shown the highest conductivity of synthesized nano ferrite is 1.93 × 10−8Scm−1. The dielectric constant as well as dielectric loss behavior recorded at room temperature and were analyzed with increasing temperature; both dielectric constant and loss tangent upsurge however with increasing frequency both are observed to reduce. Doping with Cu has the potentiality of accumulative dielectric constant and conductivity of Mn0.5Zn0.5CuxFe2−xO4 thereby improving its application for electromagnetic devices.

A Comparative Study of (Al2O3/CuO/Fe3O4) Nanoparticles on the Cementition Brick Properties

In the present study, different nanoparticles were used to improve the Cementation Brick properties, such as Nano Alumina (NA), Nano Ferrite (NF) and Nano Copper (NC). The weight of cement was partially replaced by those nanoparticles. All types of nanoparticles were added in four ratios (0.5, 1, 1.5 and 2 wt%). Three types of those nanoparticles were utilized as mixtures, first mix of NA, second mix of NF and mix of NC brick. Experimental studies were conducted to identify the optimum ratio of the mixture. The results show that 2 wt% of Nano Copper is the most relevant ratio that can improve the targeted properties. In addition, the best ratios of Nano Alumina and Nano Ferrite were observed to be 1.5 wt%. Overall, the bricks with added nanoparticles showed a better reinforcement than the bricks without adding nanoparticles. The concrete testing equipment was used to determine the bearing strength of the bricks in three different curing ages 7, 28 and 90 days. It was revealed that the bricks that contain NA particles show a better performance of strength against the compression of the tester than NC and NF particles in all ages. The ratio of 2 wt% resulted as the best ratio to decrease the water absorption of the bricks. Also, the bulk density was higher when 2 wt% ratio was used. Thus, the physical properties were significantly improved when using the nanoparticles.

Detailed analysis of structural and optical properties of spinel cobalt doped magnesium zinc ferrites under different substitutions

Spinel ferrites nanoparticles have complex considerable interest in several technical applications because of their different magnetic behavior. These magnetic nanoparticles obtain finite size and surface effects. The Co doped Mg-Zn ferrites were prepared by co-precipitation method. The structural characterization of the samples was done for Mg0.5Zn0.5-xCoxFe2O4 (X = 0.01–0.05) nano ferrites using X-ray diffraction (XRD), scanning electron microscopy (SEM), UV spectroscopy and Fourier transform infrared spectroscopy (FTIR). The cubical spinel structure of single phase has been obtained. As the concentration of Cobalt in the magnesium zinc ferrite increases, the crystallinity of the cubic spinel phase gradually increases. As increasing the concentration of Co+2 the lattice constant disorderly the lattice symmetry. Absorption spectra display a change in position of maximum absorption near the higher wavelength with increased Co2+ content. Some XRD parameters, using proposed X-ray morphology index, average crystalline size, lattice parameter, Density, Volume of unit cell, etc., have been evaluated. The absorption spectra reveal that in visible region Co-doped Mg-Zn ferrite close infrared region has low absorption rate moreover; in UV region the absorption is high. The evaluation of bandgap of Co-doped MgZnFe2O4 is the important features of its optical characteristics. The SEM image shows the non-uniform grains distributions for all compositions. The IR spectroscopy is a versatile tool for the identification of purity, functional groups, and phase of samples.

Preparation of Nano Ink Using Cobalt Ferrite and Barium Titanate for Printed Electronic Devices

Lead in our body is toxic and hazardous. Here leadfree Cobalt ferrite and Barium Titanate inks have been prepared and fabricated. The prepared inks remained stable without agglomeration or condensation during preservation. Cobalt Ferrite and Barium Titanate Nano inks have been characterized using X-ray diffraction method and UV Visible Spectroscopy. By the analysis of X-ray diffraction (XRD), the resultant inks were confirmed to be of pure Cobalt Ferrite and Barium Titanate powders with cubic structure and tetragonal structure respectively. Lattice parameters and grain size have been determined by X-ray diffraction method. UV Visible Spectroscopy analysis has been done to obtain the band gap energy of the prepared inks. The preparation and characterization of Cobalt Ferrite and Barium Titanate Nano inks are comprehensively demonstrated in this paper.

Review paper on nickel-zinc nano ferrite

Spinel ferrites are very popular due to their large flexible properties and loss eddy current loss. Among spinel ferrites, Ni-Zn nanoferrites plays vital in industry because of its numerous applications in r due to its high permeability and high mechanical strength. Ni – Zn are very good magnetic materials and its magnetic, electrical and structural properties can be varied by changing ions at tetrahedral and octahedral sites. Ni-Zn nano ferrites papers were studied and summarized the conclusions of different studied by varying synthesis methods, varying shape of nanomaterials, changing dopant, changing sintering temperature and changing annealing temperature.

Synthesis and tuning the electro-magnetic properties of Co-Cr substituted Sr-hexaferrite towards diverse usages

Strontium hexaferrite is one of the powerful commercial magnets due to its unique characteristic combination of physical, magnetic, and dielectric properties. According to the necessity, their magnetism may be altered as either hard or soft by substitutional effectiveness of the transition elements and optimization of processing parameters. Here, SrFe12-(x+y)CoxCryO19 (x,y = 0,0; 0,1; 0.25,0.75; 0.50,0.50; 0.75,0.25; 1,0) nano ferrites have been successfully synthesized by the sol–gel self-propagation process and the impacts of Co-Cr on the microstructure, densification, magnetic, dielectric, and electrical properties have been analyzed. The XRD data discloses the crystalline ferrite phase with a hexagonal structure (P63/mmc). It is found that the magnetic properties can be tuned up effectively by the substitutions. The samples show a range (0.02–0.48) of the squareness (Mr/Ms) ratio suitable for diverse industrial applications. SrFe11CrO19 composition reveals magnetic improvement in Ms (60 emu/g) and Hc (6.3 kOe) along with decent energy product, i.e., 27.17 MGOe, optimized to approach for a permanent magnet. SrFe11Co0.75Cr0.25O19 & SrFe11CoO19 compositions show a great dilution in hard magnetism having Ms of 71 emu/g along with Hc of 36.21 Oe and 3.23 Oe, respectively. It has opened up the opportunity of possible emersion of the hard magnet in the magnetic recording media application. The proposed work is expected to offer a good notion to modify strontium hexaferrite in order to expand its application areas.

Influence of Cadmium Substitution on Structural and Mechanical Properties of Co‐Ni Nano Ferrite Synthesized by Co‐Precipitation Method

AbstractThe objective of this work is to synthesize cadmium doped cobalt nickel ferrite (Co0.5Ni0.5Cd1.5xFe2‐xO4) series with x = 0.0, 0.1, 0.2, 0.3, 0.4, 0.5 by co‐precipitation method and analysis of structural properties using X‐ray diffraction (XRD), Fourier‐transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) characterization. The XRD characterization of the samples confirms the cubic spinel structure. Grains in the samples are granular in nature as depicted by SEM images. The FTIR spectra of synthesized ferrites show two strong absorption bands (ν1 and ν2) in the range 400–600 cm‐1 belonging to tetrahedral (A) and octahedral (B) interstitial sites. Williamson Hall and size‐strain plot results show the variation in the grain size with change in doping concentration. Crystallite size D, lattice constant a, micro strain ε, x‐ray density Δx, dislocation density ρD, hopping lengths(LA and LB), bond lengths (A–O and B–O), ionic radii (rA and rB), texture coefficients [TC(hkl)], and mechanical properties are also reported.

The investigation of structural and magnetic properties of MnFe2−xWxO4 nanoparticles

The investigation of effective synthesis routes and applications of magnetic nanomaterials are of great importance in recent years. Here in this article, W3+ substituted manganese ferrite (MnFe2−xWxO4) nano particles were prepared via cost effective and a new micro emulsion strategy. The synthesized materials were first characterized by different physicochemical analyzing techniques to study the structural, spectral and magnetic properties in detail. From the XRD investigation, a cubic phase was observed in all samples of Tungsten substituted Manganese ferrites with a very minute secondary phase. Variation in lattice parameters and observed peak shifting in substituted samples directed towards introduction of tungsten ions in the spinel MnFe2O4. The change in band positions (ν1 and ν2) also suggested the incorporation of foreign impurity (W3+) in spinel lattice. From the magnetic measurement investigation, a significant rise in saturation magnetization (Ms) and coercivity (Hc) was observed. In this regard, the excellent properties and the soft magnetic behavior and of this new tungsten substituted manganese ferrite (MnFe2−xWxO4) suggested its effective utilization in sensors, switching, multilayer chip inductor and many advance technological applications.

Structural, Magnetic and DC Electrical Resistivity Studies of Ni–Zn–Cr Ferrites Prepared by the Citrate-Gel Auto-Combustion Method

Nanocrystalline chromium substituted Ni–Zn nanoferrites with composition Ni0.5Zn0.5CrxFe2−xO4 (0 ≤ x ≤ 0.25, in steps of 0.05) have been synthesized using citrate-gel auto-combustion method. The as synthesized powder of the starting composition has been characterized by using TG–DTA in air atmosphere for the temperature up to 800 °C and X-ray diffraction for its structure. Upon confirming the spinel phase for the starting composition, the chromium substituted Ni–Zn ferrite nano powders were synthesized by the similar procedure. The as synthesized powders were pressed into pellets and toroids under uniaxial pressure followed with sintering in air atmosphere for 4 h at 1100 °C for electrical and magnetic characterizations. The X-ray diffraction studies revealed a decrease of the lattice constant and considerable modification in the structure of Ni–Zn ferrite with the substitution of Cr3+ for Fe3+ ions. The room temperature FT-IR spectra displayed three significant IR absorption bands in the wave number range of 350–600 cm−1 which is a characteristic of the spinel structure. The band positions and intensities were found to vary with chromium substitution in Ni–Zn ferrite. The room temperature DC electrical resistivity and activation energy for conduction in the Ni–Zn–Cr ferrite samples were measured by using the two-probe method while the AC resistivity studies were carried out in the frequency range of 1 kHz to 13 MHz and the all the observations have been discussed in the light of existing understanding.

Impact of Mg doping on structural, spectral and dielectric properties of Cd–Cu nano ferrites prepared via sol-gel auto combustion method

A series of Cd0·5Cu0.5-xMgxFe1.95La0·05O4 (x = 0.0, 0.125, 0.25, 0.375, 0.5) nano ferrites was synthesized via sol-gel auto combustion route. XRD analysis confirmed the development of spinel ferrites. Different structural parameters like lattice constant, tetrahedral and octahedral radii, oxygen ion parameter, tolerance factor, bond lengths, edge lengths and interionic distances were calculated from XRD data. It was observed that by increasing the Mg2+ concentration, lattice constant and crystallite size were increased. Energy band gap was measured using UV–vis spectroscopy and found in the range 1.79–2.36 eV. Dielectric properties of the prepared samples were also studied and it was found that dielectric constant and ac conductivity were decreased with increase in Mg2+ content. The study indicates that Cd0·5Cu0.5-xMgxFe1.95La0·05O4 nano ferrites have great potential to be utilized in high frequency devices as microwave absorbing material and in optoelectronic devices.

Effect of Mn2+ doping on structural, magnetic and electrical properties of Ni0.5-xMnxCu0.2Cd0.3Fe2O4 nano ferrites prepared by sol-gel auto combustion method for high-frequency applications

The mixed ferrite samples Ni0.5-xMnxCu0.2Cd0.3Fe2O4 (0.0 ≤ x ≤ 0.3, in steps 0.1) have been prepared utilizing the sol-gel auto combustion method. From the XRD peak and FT-IR spectra, the formation of spinel ferrites has been confirmed. From XRD data, both the experimental and hypothetical lattice constant values have been calculated. Surface morphology and particle orientation have been investigated by TEM and FESEM images. The purity and the elemental distribution have determined from EDS spectra. Magnetic parameters have been measured from VSM data. Over an extensive range of frequency (20Hz-15MHz), dielectric properties, electric modulus, impedance spectroscopy, and ac conductivity have been recorded by an impedance analyzer. The minimum dielectric loss has been observed in the high-frequency area. In the impedance spectroscopy graph, grain and grain boundary outcome has been revealed. Typical increasing behavior has been seen from the ac conductivity response of ferrite samples with an enhancement in frequency.

The magnetic property alterations due to transition from barium ferrite (BaFe2O4) nano rods to barium carbonate (BaCO3) quantum dots

Barium carbonate (BaCO3) quantum dots and barium ferrite (BaFe2O4) nano rods were synthesized by combustion method. The structural, morphological and magnetic properties were characterized by X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), field emission scanning microscopy (FESEM), Transmission Electron Microscopy (TEM), Energy-dispersive X-ray spectroscopy analysis (EDAX) and vibrating sample magnetometer (VSM). The crystallinity with orthorhombic structure of BaCO3 and BaFe2O4 nanoparticles were confirmed by XRD pattern. The FTIR spectra also indicate the formation of both BaCO3 and BaFe2O4 from specific metallic vibration. The morphological analysis confirms the formation of BaCO3 quantum dot and barium ferrite nano rods which is clearly visualized from the FESEM and TEM images. The annealing process caused this vivid transition in morphologies. The BaCO3 quantum dot produced an important change in magnetic property over BaFe2O4 nanorods which are evidenced from saturation magnetization (Ms) and coercivity (Hc).

Bond performance of a hybrid coating zinc-rich epoxy incorporating nano-ferrite for steel rebars subjected to high temperatures in concrete

The main issues in common steel rebar coatings are the reduction in bond strength and inconvenience to high temperatures. Inspired by these facts, a hybrid coating zinc-rich epoxy (ZRE) incorporating nano-ferrite (NF) (NF-ZRE) was prepared with different percentages. The performance of bond strength was studied at different temperatures up to 600 °C in the presence of ZRE coating. In addition, the results of the uncoated specimens and other categories with an additional layer of Sikadur-31 (SDE) epoxy bonding coating over ZRE coating (SDE-ZRE) were compared. This experiment was performed for two different mixes, namely, normal (MN) and silica fume mixes (MSF). The effect of adding NF with different percentages of ZRE on bond strength in the MSF mix was investigated, and all results at distinct temperatures were compared. The compressive strength test and scanning electron microscopy (SEM) were conducted to explain the obtained results of bond strength. Results showed that the residual bond strength of uncoated and ZRE-coated specimens in the MSF mix was better than that of MN at temperatures up to 400 °C. The specimens with SDE-ZRE were deboned at temperatures over 300 °C. Furthermore, the residual bond strengths of specimens incorporating NF-ZRE, specifically in 2% NF, recorded the greatest values at high temperatures up to 500 °C. All the attained results were verified and emphasized through the compressive strength test and SEM.

Crystallographic and magnetic phase stabilities of NiFe2O4 nanoparticles at shocked conditions

In the present article, we have reported the crystallographic and magnetic phase stabilities of nickel ferrite nano particles (NiFe2O4 NPs) at different number of shock wave-loaded conditions. Series of shock pulses have been loaded on the test samples such as 50,100 and 150 shock pulses with Mach number 2.2. Powder X-ray diffractometer (XRD), diffused reflectance spectroscopy (DRS) and vibrating-sample magnetometer (VSM) are utilized to examine the crystallographic, electronic and magnetic phase stabilities. The observed XRD, DRS and VSM results indicated that no crystallographic, electronic and magnetic phase transitions occurred by the impact of shock waves. Fascinatingly, SEM images show the shock wave assisted shape modification at 150 shocks. The accomplished magnetic phase stability results have compared with our previous report on Fe2O3 NPs for better understanding the structure-property stabilities of title ferrite against the impact of shock waves. Based on the observed results, we wish to suggest that the title material is a suitable candidate for high pressure, high temperature applications and for aerospace applications due to the outstanding shock resistance properties.

A novel low cost nonenzymatic hydrogen peroxide sensor based on CoFe2O4/CNTs nanocomposite modified electrode

A novel and low cost electrochemical method has been developed for the non-enzymatic detection of the hydrogen peroxide using cobalt ferrite (CoFe 2 O 4 ), carbon nano tubes (CNTs) modified glassy carbon electro (GCE), and the sensor has been named as CoFe 2 O 4 /CNTs/GCE. The CoFe 2 O 4 /CNTs nanocomposite has been successfully synthesized through a facile one-step hydrothermal method. The crystal structure, morphology and composition of the nanocomposite are characterized by XRD, Raman, XPS, FE-SEM, and HR-TEM measuremnets. The particle size of ferrite nano composite is obtained as ~17 nm. Electrochemical properties of the CoFe 2 O 4 /CNTs/GCE are investigated using various electrochemical techniques such as; cyclic voltammetry, electrochemical impedance spectroscopy and square wave voltammetry. The constructed CoFe 2 O 4 /CNTs/GCE showed superior electrochemical activity towards H 2 O 2 sensing compared with the CoFe 2 O 4 /GCE and bare GCE. The sensor produces a linear response in the range of 5–50 μM and the detection limit is obtained as 0.05 μM (S/N = 3) using chronoamperometry techniques and the square wave voltammetry technique generated the linear response in the range of 5–100 μM and the detection limit of 0.02 μM (S/N = 3). The developed sensor has shown suitable anti-interfering property with good stability towards the detection of H 2 O 2 . The CoFe 2 O 4 /CNTs modified electrode has been applied to determine H 2 O 2 in the commercially available juice samples. The performance of the sensor is comparable or superior to several others commonly sensors used for the analysis of H 2 O 2 , which indicates its promising practical application. • Cobalt ferrite and CNT nano composite has been synthesized using hydrothermal route. • Nano composite materials has been characterized with suitable redox states. • Materials shown excellent electrocatalytic activity for hydrogen peroxide oxidation. • Analytical method is developed with limit of detection 0.02 μM (S/N = 3). • Chronoamperometry could be obtained, suitable for continuous monitoring.

Utility of Silane-Modified Magnesium-Based Magnetic Nanoparticles for Efficient Immobilization of Bacillus thermoamylovorans Lipase.

Enzymes and protein's immobilization on magnetic nano supports is emerging as a promising candidate in the food, medical field, and areas of environmental studies. This work presents a study on purified Bacillus thermoamylovorans lipase (BTL) by utilizing tetraethoxysilane (TEOS)-modified magnesium nano ferrite (MgNF) of 20nm size. Its structural and morphological studies were investigated by powder X-ray diffractometry, high-resolution transmission electron microscopy, etc. Binding of BTL with MgNF was supported by using Fourier transform infrared spectroscopy. Magnetic behavior was examined by the vibrational sample magnetometer and Mössbauer spectrometer graphs. The enzymatic activity of BTL before and after immobilization was studied at different temperatures and reaction time. As per the Lineweaver-Burk plot, immobilized lipase has more biological affinity for fatty acids in comparison to the free lipase, and Kmax values of immobilized and free BTL were computed as 6.6 and 7.5mM respectively, with excellent reusability(> 50%) even till 13 consecutive assay runs. Graphical Abstract.

Structural, Thermal and Morphology Studies of Cu-CoZnFe2O4 Nano Ferrites by Combustion Method

A detailed investigation on the effect of preparation method on the structural, thermal and morphology Cu-Co ferrite nanoparticles prepared by solution combustion method. The resulting ferrites were calcined at 450℃ and 750℃. Sharper X-ray diffraction (XRD) peaks were observed for the samples calcined at 750℃, indicating greater crystallinity of the samples calcined at higher temperature. Average crystallite sizes fell in the ranges of 30.4–42.1 nm for the samples calcined at 450℃ and 750℃, respectively. Agglomeration of particles was observed in the scanning electron microscopy (SEM) images. Cumulative acidity decreased for the samples calcined at higher temperature. The results underline the effect of preparation conditions on the morphology, crystallite size, and magnetic properties of nano ferrites. The thermal properties such as onset of decomposition and glass transition temperatures were determined by Thermo Gravimetric Analysis (TGA/DSC). The TGA data shows that nanoferrites have significantly enhanced thermal stability. Thermal studies on as prepared samples have been undertaken over a wide range of decomposition at room temperature to up to 1000⁰C.

Synthesis Condition and Treatment Assisted Tuning of Structural, Magnetic Properties and Bandgap of Ni Nano Ferrite

Synthesis Condition and Treatment Assisted Tuning of Structural, Magnetic Properties and Bandgap of Ni Nano Ferrite

Synthesis Condition and Treatment Assisted Tuning of Structural, Magnetic Properties and Bandgap of Ni Nano Ferrite

Synthesis Condition and Treatment Assisted Tuning of Structural, Magnetic Properties and Bandgap of Ni Nano Ferrite

Improved Electrical Properties Displayed by Mg2+-Substituted Cobalt Ferrite Nano Particles, Prepared Via Co-precipitation Route

In this reported study, magnesium-substituted cobalt ferrite nanoparticles (Co1−xMgxFe2O4, x = 0.0, 0.20, 0.35, 0.50) have been investigated. The samples were prepared via a wet chemical co-precipitation route and were calcinated at 800 °C for 6 h. The structural, electrical, and dielectric properties of these samples were studied using XRD, SEM, FTIR, impedance analyzer, and LCR meter. The XRD diffractograms established the development of FCC spinel arrangement with decreasing crystallite size from 20 to 30 nm without any additional impurity peak confirming the purity of the samples synthesized. The FTIR spectra established the existence of tetrahedral (A) and octahedral (B) lattice sites in the structural arrangement. The SEM images showed uniform nano-spherical particle formation with minimum porosity. No extra phase or impurity was found, confirming the effectiveness of the co-precipitation route. The dielectric properties of the synthesized samples measured at ambiance temperature against frequency range of 103 Hz to 5 MHz showed massive enhancement of dielectric constant (on the order of 104 at 100 Hz) which was comparable to traditional ceramics (having a dielectric constant in the range of 104–106), which are often rendered suitable for capacitor applications. Furthermore, the low values of dielectric loss tangent at high frequencies verified its potential usage in microwave applications. A significant contribution of both long- and short-range order in hopping as well as an increase in grain boundary density was confirmed by complex electric modulus analysis. The DC electrical resistivity measurement against increasing temperatures was done, showing a typical decreasing trend with increasing temperature, validating the semiconductor nature of synthesized nanoparticles with varying compositions. The drift mobility was further calculated from the DC resistivity data.