Co-Zn Ferrite Nanoparticles Research Articles

Structural, Electrical and Magnetic Properties of Low Dimensional Pr-Doped Co-Zn Ferrite Nanoparticles

Structural, Electrical and Magnetic Properties of Low Dimensional Pr-Doped Co-Zn Ferrite Nanoparticles

Tuning the photocatalytic performance through magnetization in Co-Zn ferrite nanoparticles

In this work, the link between the photocatalytic performance of Co-Zn ferrite nanoparticles and the net magnetic moment is analyzed. CoxZn1-xFe2O4 nanoparticles (0 ≤ x ≤ 1) were synthesized by co-precipitation method and different physicochemical techniques were employed to characterize the samples (X-ray diffraction, Transmission Electron Microscopy (TEM), BET surface area, Diffuse Reflectance Spectroscopy (DRS), Photoluminescence spectroscopy, Z-potential, SQUID magnetometry). Enhanced photocatalytic degradation (maximum degradation ratios of two emerging pollutants, phenol and toluene) are found in those nanoparticles (0.4 ≤ x ≤ 0.6) with optimum magnetic response (i.e. superparamagnetism at room temperature and high saturation magnetization). The magnetization of the nanoparticles turns out to be the determining factor in the optimization of the photocatalytic response, since there is no clear relationship with other physicochemical parameters (i.e. specific surface area, isoelectric point, band gap energy or photoluminescence). These results support the current field of research related to photocatalytic performance enhancement through magnetic field effects.

Enhancing the magnetization, electric resistivity and mechanical properties of silicone rubber loaded by Co-Zn ferrite nanoparticles as filler

High temperature vulcanized silicone rubber samples filled with Co0.5Zn0.5Fe2O4 ferrite nanoparticles were prepared using an ordinary standard rubber mixer. The compounds were prepared by dry mixing in two roll-mixing mills (outside diameter 470 mm, working distance 300 mm, speed of slow roll 24 rpm and fraction ratio of 1:1.4). Structure and Morphology of Co-Zn ferrite were characterized by X-ray diffraction and transmission electron microscope (TEM). The homogeneity of Co-Zn nanoferrite-filled silicone rubber was evaluated by scanning electron microscope (SEM). The influences of ferrite concentration on the rheological and the physico mechanical properties: tensile strength, elongation at break, Young’s modulus were measured. An enhancement of those properties were noticed by increasing ferrite load till 8 phr. The hardness showed an enhancement for all composite samples. Magnetization of the samples showed an increase with high rate at high ferrite concentration while the electric resistivity decreases up to 8 phr ferrite loaded sample then increases for higher ferrite loads. These results were discussed and interpreted in the light of the morphology and different interactions between the phase of ferrite and rubber matrix. Comparisons which were held between the obtained results with those in the literature showed superiority for the values of measured properties in this study.

Electromagnetic wave absorption properties of cobalt-zinc ferrite nanoparticles doped with rare earth elements

Traditional ferrites are of poor electromagnetic wave (EMW) absorption while doping rare earth elements (REEs) can greatly enhance their permeability to improve the EMW loss performance. In this study, Co-Zn ferrite nanoparticles doped with various amounts of REEs (Gd3+, Nd3+ and Pr3+) were synthesized by a hydrothermal method, and their particle morphology and an EMW absorption performance were characterized by using transmission electron microscopy (TEM) and a Vector network analyzer (VNA). The results show that the initial spherical Co-Zn ferrite nanoparticles present an irregular quadrilateral structure after Gd3+ doping, and the average particle size of Co0.5Zn0.5−xGdxFe2O4 increases from 26 to 50 nm with x increasing from 0 to 0.35. At x of 0.25, the reflectivity absorbance achieves −27.94 dB at 18 GHz with the effective absorption bandwidth (EAB) of 4.08 GHz at a sample thickness of 2.5 mm. When Nd3+ doping amount reaches x = 0.3, the minimum reflection loss (RL) is −25.63 dB at 18 GHz and EAB is 3.91 GHz. Doping Pr3+ (x = 0.25) in the sample broadens EAB, and the minimum RL is −16.1 dB at 16.81 GHz and EAB is 7.31 GHz. This study shows that the magnetic moment produced by doping REES can form magnetic domains, which affects the incident EMW and improves the magnetic loss. It is expected that REEs-doped Co-Zn ferrite nanoparticles can be used as efficient electromagnetic shielding materials in aerospace.

Inter-atomic bonding and dielectric polarization in Gd3+ incorporated Co-Zn ferrite nanoparticles

A series of ferrite with a chemical composition Co0.7Zn0.3GdxFe2−xO4 (where x=0.0 to x=0.1) were prepared by sol-gel auto-combustion method. X-ray diffraction pattern were used to determine the crystal structure and phase formation of the prepared samples. Scanning electron microscopy is used to study the surface morphology of the prepared samples. Elastic properties were determined from the infrared spectroscopy. Debye temperature, wave velocities, elastic constants found to increase with the increase in Gd3+ substitution. Dielectric properties such as dielectric constant and dielectric loss were studied as a function of Gd3+ substitution and frequency. Dielectric constant decreased with the increase in frequency and Gd3+ substitution. Behavior of dielectric properties was explained on the basis of Maxwell-Wagner interfacial polarization which in accordance with Koops phenomenological theory. Real and imaginary part of impedance was studied as a function of resistance and Gd3+ substitution. The behavior of impedance is systematically discussed on the basis of resistance-capacitance circuit.

Synthesis and characterization of Co-Zn ferrite nanoparticles for application to magnetic hyperthermia

Co-Zn ferrite nanoparticles have been investigated, aiming at a further improvement of the magnetic hyperthermia properties for bio-medical applications. We precisely tune the magnetic and the thermal properties of CoxZn1−xFe2O4 nanoparticles, prepared by using a high-temperature thermal-decomposition method, by chemically controlling the cation. The structure and the magnetic properties as well as the AC-heating characteristics of the synthesized CoxZn1−xFe2O4 were measured by using X-ray diffraction (XRD), vibrating sample magnetometer, magneTherm device and Mossbauer spectroscopy. The analysis of the XRD patterns confirmed the spinel phase, the crystalline size, and the lattice parameter. The magnetic behavior of Co-Zn ferrite was studied with M-H hysteresis curve measurements at room temperature. Also, the thermal properties were measured under an external applied field of 250 Oe at 112 kHz. In addition, we plasma-treated the samples with magnetic and thermal excellent characteristics for 30 min at room temperature. The cation distribution was investigated with Mossbauer spectroscopy and further analyzed with one sextet for the tetrahedral A site and four six-lines for the octahedral B1, B2, B3, and B4 sites.

Metal ferrite nanoparticles: Synthesis, characterization, and studies on decontamination of sulfur mustard

Mg, Ca, Mn, Co, Ni, Cu, Zn, Mn-Zn, and Co-Zn metal ferrite and mixed metal ferrite nanoparticles were synthesized by co-precipitation method and were characterized by using transmission electron microscopy, X-ray diffraction, and nitrogen adsorption techniques. Transmission electron microscopy data indicated the formation of metal ferrite and mixed metal ferrite nanoparticles with particle sizes varying from 2 to 88 nm. X-ray diffraction data indicated the formation of metal ferrite and mixed metal ferrite nanoparticles with spinel phase. The metal ferrite nanoparticles were found to be mesoporous and exhibited surface area values in the range of 62–257 m2/g. The ferrite nanoparticles were used in decontaminating sulfur mustard and the reactions exhibited first order behavior. Out of them, Ni, Zn, and Co-Zn ferrite nanoparticles showed greater decontamination efficiency in comparison to other ferrite nanoparticles. While Ni, Zn, and Co-Zn ferrite nanoparticles decontaminated 99.99% of sulfur mustard within 10 h other ferrite nanoparticles took about 16 h to degrade the same. The metal ferrite and mixed metal ferrite nanoparticles degraded toxic sulfur mustard into relatively non toxic products like chloro ethyl vinyl sulfide, hydroxy ethyl vinyl sulfide, hemisulfur mustard, and 1,4-oxathiane. The promising decontamination properties of metal ferrite nanoparticles against sulfur mustard were attributed to the basic sites, Lewis acid sites, and the presence of these sites was confirmed by CO2 and NH3 temperature programmed desorption.

Combustion and Coprecipitation Synthesis of Co–Zn Ferrite Nanoparticles: Comparison of Structure and Magnetic Properties

In this study, we used urea and ammonia to synthesize zinc cobalt ferrites via microwave‐assisted hydrothermal method from metallic nitrates. It was figured that despite the common synthesis method and equal amount of nitrates, magnetic properties of nanoparticles were different. Changes in magnetic properties are discussed based on factors such as nanoparticles’ size, surface atom spins, cationic distribution, magnetocrystalline energy. Nanoparticles synthesized with ammonia showed lower magnetization while higher magnetocrystalline energy and greater coercivity was obtained due to better cationic distribution. It was also revealed that by increasing magnetization, the susceptibility of nanoparticles increases and then declines.

Mechanical and dielectric properties of cobalt–zinc nanoferrite/nitrile butadiene rubber composites

Nitrile butadiene rubber (NBR) samples filled with cobalt–zinc (Co-Zn) ferrite nanoparticles (Co1− xZn xFe2O4, where x = 0, 0.2, 0.4, 0.6, 0.8, 0.9, 0.95 and 1) were prepared. The structure and morphology of Co-Zn ferrite nanoparticles were investigated using X-ray diffraction, transmission electron microscopy, and Fourier transform infrared (FTIR) spectroscopy, while the structure of the Co-Zn nanoferrite-filled NBR composites was studied using scanning electron microscopy and FTIR spectroscopy. The influence of ferrite composition on cure characteristics, mechanical properties and hardness showed an improvement up to x = 0.8. Dielectric parameters showed an enhancement with ferrite composition.

Magnetic, Electric and Structural Properties of Ni Substituted Co-Zn Ferrite Nanoparticles Synthesized by Sol-Gel Method

Nickel substituted CoxZn0.8-x Fe2O4 (x=0.2,0.5 and 0.6) ferrite were synthesized by Sol-gel auto combustion method. The powders were sintering at 400 o c and 700 o c for 2hrs to densify properly. The samples were characterized by XRD, SEM and FTIR and Magnetic properties. The XRD used to analyze phase structure and lattice parameters. The FTIR spectra confirmed that synthesis material is ferrite. Morphology of ferrite powders were investigated by using SEM. Porosity of synthesis ferrite is measured. The saturation magnetization increases with increasing Co-Zn concentration. Resistivity of ferrite material is may be decreases due to vary concentration of Co and Zn. this paper we present a study of the magnetic and structural properties of Ni0.2CO0.2Zn0.6Fe2O4, Ni0.2CO0.5Zn0.3Fe2O4 and Ni0.2CO0.6Zn0.2Fe2O4 nanocomposites of different composition. The composition, crystal structure, morphology, and size distribution of Ni-Co-Zn ferrite nanocrystals can be controlled by adjusting the synthesis route and molar ratio of materials in the initial mixtures. The synthesized nano crystals have been characterized by XRD, SEM, FTIR, and Magnetic Properties presented below are the details of investigation. II. Experimental: The Ni0.2CO0.2Zn0.6Fe2O4, Ni0.2CO0.5Zn0.3Fe2O4 and Ni0.2CO0.6Zn0.2Fe2O4 ferrite powders were prepared by co-precipitation and hydro thermal technique using iron nitrate, zinc nitrate, cobalt nitrate, and nickel nitrate as reaction agent. To obtain Ni0.2CO0.2Zn0.6Fe2O4, Ni0.2CO0.5Zn0.3Fe2O4 and Ni0.2CO0.6Zn0.2Fe2O4 ferrite powders we have mixed AR grade iron nitrate, zinc nitrate, cobalt nitrate, and nickel nitrate with double distilled water. Citric acid was used as a chelating agent because it plays an important role in homogeneous mixture formation of metal cations. Reaction procedure was carried out in air atmosphere at room temperature. The composition was well shake and pH of solution is maintained as 7 by adding ammonia. The prepared solution was stirred on magnetic stirrer at low temperature 80 0 C to form a gel. The prepared ferrite samples were annealed for 400 0 C and 700 0

Structural and magnetic properties of Co1-xZnxFe2O4 nanoparticles

Co1-xZnxFe2O4 nanoparticles, prepared by the polyvinyl alcohol sol—gel method, have been investigated by x-ray diffraction and Mössbauer spectroscopy. These results are compared with those for the bulk material. The lattice parameters of CoZn ferrite nanoparticles are larger than those of the bulk material. Thermal scanning of Mössbauer measurement shows that the transition temperatures for nanoparticles are higher than those of the bulk material except for the sample CoFe2O4.