Effect of composition on structural and magnetic properties of nanocrystalline ball milled Ni1−xZnxFe2O4 ferrite (original) (raw)

Structure and magnetic properties of nanocrystalline Ni0·64Zn0·36Fe2O4powders prepared by ball milling

Powder Metallurgy, 2013

In this study, nanocrystalline Ni 0?64 Zn 0?36 Fe 2 O 4 powders were prepared using a planetary ball mill. The evolution of the microstructure and magnetic properties during the milling were studied by Xray diffraction technique, scanning electron microscopy, transmission electron microscopy and vibrating sample magnetometre. It is revealed from the results of the phase analysis that nanocrystalline Ni 0?64 Zn 0?36 Fe 2 O 4 ferrite with average crystallite size of 6?18 nm and non-uniform lattice strain of 0?33% has been formed after 60 h of milling time. A progressive increase of saturation magnetisation and a dramatic decrease in coercivity were also observed with increasing milling time.

Structural and magnetic properties of nanocrystalline ZnFe2O4 powder synthesized by reactive ball milling

HAL (Le Centre pour la Communication Scientifique Directe), 2011

The zinc ferrite (ZnFe2O4) has been obtained in nanocrystalline state by reactive milling in a high energy planetary mill from a stoichiometric mixture of oxides (ZnO and α-Fe2O3). A post milling annealing promotes the solid state reaction, improves the ferrite crystalline state and removes internal stresses. The formation of zinc ferrite was studied by X-ray diffraction and magnetic measurements. The chemical homogeneity and morphology of the powders were studied by X-ray microanalysis and scanning electron microscopy. The mean crystallite size after 16 h of milling was found to be 18 ± 2 nm. The lattice parameter of the obtained ferrite depends on the milling time and subsequent annealing treatment. It is lower than that of zinc ferrite obtained by the ceramic method. The evolution of the magnetization versus milling time is discussed in terms of milling induced cations reorganisation into the spinel structure.

Characterization of nanodimensional Ni-Zn ferrite prepared by mechanochemical and thermal methods

Journal of Physics: Conference Series, 2010

Nickel zinc ferrite nanoparticles, Ni 1-x Zn x Fe 2 O 4 (x = 0, 0.2, 0.5, 0.8, 1.0), with dimensions below 10 nm have been prepared by combining chemical precipitation with highenergy ball milling. For comparison, their analogues obtained by thermal synthesis have also been studied. Mössbauer spectroscopy, X-ray diffraction, and magnetic measurements are used for the characterization of the obtained materials. X-ray diffraction shows that after 3h of mechanical treatment ferrites containing zinc are formed, while 6h of treatment is needed to obtain NiFe 2 O 4. The magnetic properties of the samples exhibit a strong dependence on the phase composition, particle size and preparation method.

Effects of Milling Atmosphere and Increasing Sintering Temperature on the Magnetic Properties of Nanocrystalline Ni 0.36 Zn 0.64 Fe 2 O 4

Journal of Nanomaterials, 2015

Nanocrystalline Ni 0.36 Zn 0.64 Fe 2 O 4 was synthesized by milling a powder mixture of Zn, NiO, and Fe 2 O 3 in a high-energy ball mill for 30 h under three different atmospheres of air, argon, and oxygen. After sintering the 30 h milled samples at 500 ∘ C, the XRD patterns suggested the formation of a single phase of Ni-Zn ferrite. The XRD results indicated the average crystallite sizes to be 15, 14, and 16 nm, respectively, for the 30 h milled samples in air, argon, and oxygen atmospheres sintered at 500 ∘ C. From the FeSEM micrographs, the average grain sizes of the mentioned samples were 83, 75, and 105 nm, respectively, which grew to 284, 243, and 302 nm after sintering to 900 ∘ C. A density of all the samples increased while a porosity decreased by elevating sintering temperature. The parallel evolution of changes in magnetic properties, due to microstructural variations with changes in the milling atmosphere and sintering temperature in the rage of 500-900 ∘ C with 100 ∘ C increments, is also studied in this work.

Structure and magnetic properties of Ni0.64Zn0.36Fe2O4 nanoparticles synthesized by high-energy milling and subsequent heat treatment

Journal of Materials Science: Materials in Electronics, 2014

High energy ball milling and subsequent annealing were applied to synthesize nanocrystalline Ni 0.64 Zn 0.36 Fe 2 O 4 ferrite from a powder mixture of pure metal Zn, Fe 2 O 3 and NiO in an oxygen atmosphere. The structural and phase evolution of powder particles after different milling times were studied by X-ray diffractometry. The XRD results showed that a Ni-Zn ferrite was formed with some residual Fe 2 O 3 by annealing a 30-hmilled sample at as low as 400°C for 2 h. The average crystallite size of the 30 h-milled powder was estimated to be about 15 nm which grew to 21 nm after annealing at 500°C for 2 h. TEM image showed an agglomerated state of particles for 30 h-milled powders. FT-IR analysis indicated two absorption bands in the Ni-Zn ferrite structure related to octahedral and tetrahedral sites, respectively, in the range of 400-600 cm -1 . Thermogravimetric analysis showed a mass loss about 2 % for as-received powder mixture below 400°C; after that, it was almost stable. The Ni-Zn ferrite formation mechanism was detected to be in three stages: oxidation of zinc, diffusion of ZnO in Fe 2 O 3 and the formation of ZnFe 2 O 4 , and diffusion of NiO in ZnFe 2 O 4 and the formation of Ni-Zn ferrite. Vibrating sample magnetometery results revealed that a saturation magnetization of the 30 h-milled sample was about 5 emu/ g which increased to 16 emu/g after annealing at 400°C due to a reduction in density of lattice imperfections and strain.

Magnetic and structural properties of NiFe 2O 4 ferrite nanopowder doped with Zn 2+

Journal of Magnetism and Magnetic Materials, 2008

This work involved an investigation to ascertain how the substitution of nickel ions for zinc ions affects the structural, morphological and magnetic properties of NiFe2O4 ferrite samples. Ni1−xZnxFe2O4 (x=0.0, 0.3 0.5, 0.7) powders were prepared by combustion reaction and characterized structurally by X-ray diffraction. The specific surface area of the powders was determined by the nitrogen adsorption method (BET). Magnetization measurements were taken using an alternative gradient magnetometer (AGM), which revealed that the powders prepared by combustion reaction resulted in nanosized particles with a particle size of 18–27 nm. The crystallite size and lattice parameter increased as the concentration of Zn increased. Moreover, augmenting the Zn content in the NiFe2O4 ferrite increased the saturation magnetization and coercive field.

The effect of sintering temperature on evolution of structural and magnetic properties of nanostructured Ni0.3Zn0.7Fe2O4 ferrite

Journal of Nanoparticle Research, 2013

Nanocrystalline Ni 0.3 Zn 0.7 Fe 2 O 4 ferrite was synthesized by the sol-gel auto-combustion method. The structural, morphological, and magnetic properties of samples, sintered at different temperatures of 350-1,200°C, have been studied using X-ray diffraction (XRD), field emission scanning electron microscope, Fourier transform infrared (FTIR) spectroscopy, vibrating sample magnetometer (VSM), and AC susceptibility. XRD results indicated that the average crystallite sizes are in the range of *13 to *58 nm. The activation energy of crystallization of Ni 0.3 Zn 0.7 Fe 2 O 4 ferrite was found to be 12.46 kJ mol-1. Also, the spinel phase formation was further monitored by the FTIR analysis. VSM studies of the samples indicate that magnetization increases with the crystallite size and the maximum magnetization (49.42 emu g-1) observed in the sample sintered at 1,200°C. The coercivity increases with increasing the crystallite size and reaches a maximum value of 13.82 Oe, then decreases. Also, the low temperature-sintered samples (350 and 400°C) were superparamagnetic, due to their near-zero coercivity and remanence. AC susceptibility measurements on low temperature-sintered samples show that the interparticle interaction leads to the superspin glass-like behavior in these nanoparticle samples.

A Simple Thermal Treatment Synthesis and Characterization of Ni-Zn Ferrite (Ni0.5Zn0.5Fe2O4) Nanocrystals

Cubic structured nickel-zinc ferrite nanoparticles (Ni 0.5 Zn 0.5 Fe 2 O 4 ) have been synthesized by thermal treatment method. This simple procedure employed an aqueous solution containing only metal nitrates as precursors, polyvinyl pyrrolidone as a capping agent, and deionized water as a solvent. The solution was thoroughly stirred for 2 hour, dried at 353 K for 3 hour, the dried material crushed into powder and calcined the powder at 873 K to remove organic substances and crystallize the particles. The microstructure properties of the prepared ferrite nanoparticles were measured using FTIR, XRD, TEM, and EDX and the magnetic properties were determined using VSM and EPR. The average particle size increased from 7 to 22 nm with the increase of calcination temperature from 723 to 873 K. The saturation magnetization, coercivity field, and gfactor increased respectively from 24 emu/g, 11 G, and 2.0673at 723 K to 38 emu/g, 60 G, and 2.1227 at 873 K. This method offers simplicity, a low cost, and an environmentally friendly operation since it produces no byproduct effluents.

Effects of varying chemical composition with x = 0.1 – 0.7 on magnetic properties of soft ferrite Ni1-xZnxFe2O4

IOP Conference Series: Materials Science and Engineering, 2019

The preparation of NiZn ferrites with varying composition have been synthesized by mechanical milling method. The starting iron oxide (Fe2O3), nickel oxide (NiO), and zinc oxide (ZnO) were mixed with seven compositions of Ni1-xZnxFe2O4 with x = 0.1 – 0.7. The effects of the composition on the structural and magnetic properties of the ferrite have been investigated. Structural properties were observed by X-ray diffraction (XRD) (Bruker’s). XRD patterns match well with the characteristic reflections of f d-3 cubic spinel structure, and it confirms that the all samples have single phase. Magnetic properties characterized by Permagraph Magnet Physik at room temperature. Hysteresis curve results show that varying composition influence the magnetic properties. Sample that have the highest Ms and Mr values is when x = 0.3 with magnetization of remanence (Mr) = 30.1538 emu/g, magnetization of saturation (Ms) = 39.1642 emu/g, coercivity (HcJ) = 0.3040 kA/m, and density = 4.40 g/cm3. The high...