scholarly journals Effect of cadmium doping on structural and magnetic studies of Co-Ni ferrites

2021 ◽  
Vol 53 (3) ◽  
pp. 407-418
Author(s):  
Akshay Kulkarni ◽  
Shridhar Mathad
Keyword(s):  
Magnetic Measurements ◽  
Spinel Phase ◽  
Solid State Reaction Method ◽  
Peak Position ◽  
Initial Increase ◽  
Slight Variation ◽  
X Ray Diffraction ◽  
Magnetic Studies ◽  
Sem Images ◽  
Cadmium Doping

We report effect of influence of Cd2+ ions on Co-Ni ferrites synthesized by the solid state reaction method. The X-ray diffraction analysis confirmed the cubic spinel phase with crystallite size varies between 20-24 nm. The SEM images show tetrahedral, octahedral, granular, long bulgy structures with variety of sizes. The Raman spectra for samples with x = 0.1 and x = 0.4 shown peaks corresponding to Alg, Eg and T2g which very closely match with NiFe2O4 spectra with slight variation in peak position as an effect of different chemical formula. Magnetic measurements were carried out at room temperature. It is found that substitution influenced the magnetic properties. Saturation magnetization decreased from 52.74 to 32.68 emu.gm-1 and coercivity shown an initial increase and then a continuous decrease, with increase in the Cd2+ substitution. Retentivity is found to be varying between 10.1 emu/gr - 6.21 emu/gr.

scholarly journals Enhancement in magnetic and electrical properties of Ni substituted Mg ferrite

2018 ◽  
Vol 36 (4) ◽  
pp. 644-654
Author(s):  
K. Ramarao ◽  
B. Rajesh Babu ◽  
B. Kishore Babu ◽  
V. Veeraiah ◽  
K. Rajasekhar ◽  
...  
Keyword(s):  
Spinel Phase ◽  
Solid State Reaction Method ◽  
Wave Number ◽  
X Ray Diffraction ◽  
Magnetic Studies ◽  
Ionic Radii ◽  
Number Range ◽  
X Ray ◽  
Ft Ir ◽  
The Difference

AbstractIn this work, Ni substituted magnesium spinel ferrites having general formula Mg1−xNixFe2O4 (where x = 0.0, 0.1, 0.15, 0.2, 0.25 and 0.3) were synthesized by standard solid state reaction method. All the samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), vibrating sample magnetometer (VSM), DC resistivity measurements. X-ray diffraction analysis confirmed the single spinel phase. The lattice constant decreased with increasing Ni content due to the difference in the ionic radii of Mg2+ and Ni2+ ions. The FT-IR spectra reveled two prominent frequency bands in the wave number range of 400 cm−1 to 600 cm−1, which confirmed the cubic spinel structure of obtained compound and completion of chemical reaction. Magnetic studies revealed that the saturation magnetization increased with the substitution of Ni. The increase in magnetization was explained on the basis of distribution of magnetic and non-magnetic cations among A and B sites of the spinel lattice. A significant influence of cation distribution on DC electrical resistivity and activation energy was observed.

Investigations on Cu2+-substituted Ni–Zn ferrite nanoparticles

2016 ◽  
Vol 30 (32n33) ◽  
pp. 1650347
Author(s):  
Amarjeet ◽  
Vinod Kumar
Keyword(s):  
Spinel Phase ◽  
Thermo Gravimetric Analysis ◽  
Peak Position ◽  
Precipitation Method ◽  
Gravimetric Analysis ◽  
Frequency Range ◽  
X Ray Diffraction ◽  
Absorption Bands ◽  
X Ray ◽  
Zn Ferrite

[Formula: see text] ([Formula: see text] = 0.1, 0.3 and 0.5) nanoparticles were prepared by chemical co-precipitation method. The developed nanoparticles were characterized for structural properties by powder X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) techniques. Peak position in the X-ray diffraction pattern confirmed the single spinel phase of the developed particles. Infrared (IR) spectroscopy in mid-IR range showed the presence of characteristic absorption bands corresponding to octahedral and tetrahedral bonds in the spinel structure of prepared samples. Thermo-gravimetric analysis (TGA) measurements showed a considerable weight loss in the developed samples above 700[Formula: see text]C. Frequency dependence of the electrical properties of the developed material pellets was studied in the frequency range of 1 kHz–5 MHz. Temperature dependence of the dielectric constant of [Formula: see text] was studied at different temperatures, i.e. at 425, 450 and 475 K, in the frequency range of 1 kHz–5 MHz. It was found that the electrical conductivity decreases with increasing Cu[Formula: see text] ion content while it increases with the increase in temperature.

Structural, dielectric and magnetic properties of Pr-, Tb- and Dy-doped (Bi0.95RE0.05)(Fe0.95Mn0.05)O3 ceramics synthesized by solid-state reaction method

2013 ◽  
Vol 03 (04) ◽  
pp. 1350033 ◽  
Author(s):  
Radheshyam Rai ◽  
Shweta Thakur ◽  
M. A. Valente ◽  
Andrei L. Kholkin
Keyword(s):  
Magnetic Properties ◽  
Solid State ◽  
Solid State Reaction ◽  
Magnetic Measurements ◽  
Ferroelectric Properties ◽  
Solid State Reaction Method ◽  
X Ray Diffraction ◽  
Solid State Reaction Technique ◽  
X Ray ◽  
Ceramic Samples

The multiferroic ( Bi 0.95 RE 0.05)( Fe 0.95 Mn 0.05) O 3 (where RE = Pr , Tb and Dy ) has been synthesized using solid-state reaction technique. Effects of Pr , Tb and Dy substitution on the structure, electrical and ferroelectric properties of ( Bi 0.95 RE 0.05)( Fe 0.95 Mn 0.05) O 3 samples have been studied by performing X-ray diffraction, dielectric measurements and magnetic measurements. The crystal structure of the ceramic samples have a monoclinic phase. The vibrating sample magnetometer (VSM) measurement shows a significant change in the magnetic properties of Pr -, Tb - and Dy -doped ( Bi 0.95 RE 0.05)( Fe 0.95 Mn 0.05) O 3. It is seen that coercive field (Hc) and remanent magnetization (Mr) increases for Pr but decreases for Dy and Tb .

Electrical- Magnetic Transport and Magnetoresistance in La 0.7 Ca 0.3 MnO3/BN Composites

2011 ◽  
Vol 228-229 ◽  
pp. 379-384
Author(s):  
Yong Dan Zhu ◽  
Hong Hua Liao ◽  
Jian Jun Tan ◽  
An You Zuo ◽  
Jin Qiao Yi ◽  
...  
Keyword(s):  
Magnetic Measurements ◽  
Solid State Reaction Method ◽  
Boundary Region ◽  
X Ray Diffraction ◽  
Conventional Solid State Reaction ◽  
Low Field ◽  
Maximum Value ◽  
Spin Polarized ◽  
Magnetic Transport ◽  
Lower Temperature

The electrical–magnetic transport properties of (La0.7Ca0.3MnO3)(1-x)/(BN)x composites has been investigated systemically by conventional solid-state reaction method. The results of X-ray diffraction (XRD) and scanning electronic microscopy (SEM) show that BN and LCMO coexist in the composites and BN mainly goes into the grain boundary region without any chemical reaction with La0.7Ca0.3MnO3, which are in accordance with the results of the magnetic measurements. It is very interesting that with increasing of BN content level (x < 0.25), the metal–insulator transition temperature (TP) remains constant (nearly at 275K), and the resistivity increases very slowly. But when x > 0.25, TP shifts to lower temperature and the resistivity increases dramatically. The resistivity threshold of the composites occurred at x = 0.25, and specially the magnetoresistance (MR) reaches a maximum value (about 26.32 %) at 100K in an applied magnetic field of 3kOe. The results also indicate that the doped BN has an important effect on the low field MR (LFMR), which results from spin-polarized tunneling.

scholarly journals Synthesis, Characterization, and Magnetic Studies ofα-Fe2O3Nanoparticles

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Avnish Kumar Arora ◽  
Mohan Sharma ◽  
Ritu Kumari ◽  
Vivek Sheel Jaswal ◽  
Pankaj Kumar
Keyword(s):  
Iron Oxide ◽  
Magnetic Measurements ◽  
Average Crystallite Size ◽  
Area Measurement ◽  
Precipitation Method ◽  
Rhombohedral Structure ◽  
X Ray Diffraction ◽  
Magnetic Studies ◽  
Transmission Electron ◽  
Size Of Particles

Very fine nanosized metal oxide, namely, iron oxide (α-Fe2O3) has been synthesized by precipitation method using ammonia as precipitating agent and characterized by using XRD (X-ray diffraction), TGA/DTA, surface area measurement, transmission electron microscopy (TEM), and magnetic measurements techniques. XRD studies show that iron oxide was formed asα-Fe2O3instead of the commonly formed magnetite nanoparticles (Fe3O4) or a mixture of magnetite (Fe3O4) and maghemite (γ-Fe2O3, cubic), and it has rhombohedral structure. Magnetic measurements showed that iron oxide has five unpaired electrons and is ferromagnetic in nature, Ms value being 1.7 emu/g. The particle size of the synthesized iron oxide was determined by TEM. TEM images show that the size of particles of Fe2O3varied from 15 nm to 49 nm with average crystallite size 35 nm.

Preparation and Electromagnetic Properties of Manganese Zinc Ferrite/Barium Ferrite Composite Materials

2012 ◽  
Vol 519 ◽  
pp. 215-219
Author(s):  
Quan Yuan ◽  
Wang Qun ◽  
Zhi Xue Qu ◽  
Zi Xin Gu ◽  
Tong Wu
Keyword(s):  
Composite Materials ◽  
Barium Ferrite ◽  
Zinc Ferrite ◽  
Spinel Phase ◽  
Electromagnetic Properties ◽  
X Ray Diffraction ◽  
Sem Images ◽  
X Ray ◽  
Manganese Zinc ◽  
Manganese Zinc Ferrite

Abstract: Manganese zinc ferrite/barium ferrite composite materials were prepared with various content of Z type barium ferrite (0, 10, 20 wt%) using solid state reaction method. The effect of the compositon on the microstructure and electromagnetic properties of the composites are investigated by means of X-ray diffraction, scanning electron microscope and impedance analyzer. The X-ray diffraction patterns reveal that W phase of barium ferrite instead of Z phase appears in the composite sintered as well as the spinel phase. Some small hexagonal grains were observed in the SEM images and the proportion increases with increasing content of barium ferrite. The cut-off frequencies of the composite systematically shift towards high frequency from 2.5 MHz to 32.6 MHz which is attributed to the increasing of W phase. The composites show a higher frequency for the maximum of the impedance as well as a higher value of the impedance at certain frequency which may be benefit for the application at GHz frequency range.

Synthesis, Structural and Thermal Properties of Layered Perovskites SmBaMn2O5+d for SOFCs Applications

2017 ◽  
Vol 889 ◽  
pp. 195-200 ◽  
Author(s):  
Abdalla Mohammed Abdalla ◽  
Shahzad Hossain ◽  
Jun Zhou ◽  
Pg Mohammad Iskandar Petra ◽  
Abul Kalam Azad
Keyword(s):  
Electrode Materials ◽  
Solid State Reaction Method ◽  
Rietveld Analysis ◽  
Layered Perovskite ◽  
Orthorhombic Symmetry ◽  
X Ray Diffraction ◽  
Sem Images ◽  
Conventional Solid State Reaction ◽  
Perovskite Materials ◽  
Rare Earth Doped

New layered perovskite oxides with samarium (Sm+3) rare earth doped layered perovskite materials were synthesized and characterised by using X-ray diffraction, scanning electron microscopy (SEM), particle size measurements and thermogravimetric analysis (TGA). Sm0.5Ba0.5MnO3-δ and SmBMn2O5+δ, were synthesized by conventional solid state reaction method. Rietveld analysis of XRD data shows that all materials crystallize in the orthorhombic symmetry in the Pmmm space group. SEM images show porous structures which should be suitable as electrode materials for solid oxide fuel cells (SOFCs). TGA results indicate the mass loss of 0.022% for SmBMn2O5+δ. Density calculation shows the materials have about 85% relative density.

scholarly journals Characterization of superparamagnetic MgxZn1−x Fe2O4 powders

2007 ◽  
Vol 5 (1) ◽  
pp. 107-117 ◽  
Author(s):  
Violeta Kassabova-Zhetcheva ◽  
Lilyana Pavlova ◽  
Bisserka Samuneva ◽  
Zara Cherkezova-Zheleva ◽  
Ivan Mitov ◽  
...  
Keyword(s):  
Spinel Phase ◽  
Elementary Cell ◽  
Particle Sizes ◽  
X Ray Diffraction ◽  
Small Particles ◽  
Magnetic Studies ◽  
Superparamagnetic Relaxation ◽  
Diffraction Patterns ◽  
Quadruple Splitting

AbstractStructural and magnetic properties of Mgx Zn1−x Fe2O4 powders have been studied with respect to the application for thermal cancer therapy (magnetic hyperthermia). Mgx Zn1−x Fe2O4 (x=0.1–0.5) powders with particle sizes between 5 and 8 nm were produced by citrate method. The X-ray diffraction patterns of the samples correspond to a spinel phase. The lattice constant and the volume of the elementary cell increase when x changes from 0.1 to 0.5. The FTIR-spectra ascertain the spinel phase formation. The Mossbauer studies reveal the presence of extremely small particles, which undergo superparamagnetic relaxation at room temperature. The core-shell model has been applied to explain quadruple doublets. The quadruple splitting at “shells” is bigger than those at “cores” whereas the isomer shifts remain close. Magnetic studies confirm the presence of extremely small particles that behave as superparamagnetic ones.

STRUCTURE AND MAGNETIC PROPERTIES OF NONOSIZED SnO-Fe2O3 MATERIAL OBTAINED BY BALL MILLING

2010 ◽  
Vol 09 (06) ◽  
pp. 567-570
Author(s):  
AHMED M. AL-SAIE ◽  
ADNAN JAAFAR ◽  
MOHAMED BOUOUDINA
Keyword(s):  
Magnetic Properties ◽  
Saturation Magnetization ◽  
Diffraction Pattern ◽  
Ball Milling ◽  
Magnetic Measurements ◽  
Spinel Phase ◽  
Ferromagnetic Behavior ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffraction Peaks

A mixture of Fe 2 O 3 and SnO oxides has been mechanically milled to form SnFe 2 O 4 spinel phase. X-ray diffraction pattern of the milled mixture shows that after milling, both peaks of Fe 2 O 3 and SnO remain with a drastic decrease of their intensities and broadening. The appearance of a broad halo around 2θ ~ 31° indicates the formation of an amorphous phase. After annealing at 750°C for 1 h, SnO peaks disappear completely and new diffraction peaks emerge indicating the formation of a new nanophase i.e. SnO 2. Magnetic measurements of the as-milled mixture show a ferromagnetic behavior with saturation magnetization Ms = 6.8 emu/g which drastically decreases after annealing to 0.6 emu/g.

Tailoring the Magnetic Properties and Magnetocaloric Effect in Double Perovskites Sr2FeMo1–xNbxO6

2020 ◽  
Vol 12 (3) ◽  
pp. 391-397 ◽  
Author(s):  
Imad Hussain ◽  
S. N. Khan ◽  
Tentu Nageswara Rao ◽  
Riyaz Uddin ◽  
Jong Woo Kim ◽  
...  
Keyword(s):  
Magnetic Measurements ◽  
Spontaneous Magnetization ◽  
Double Perovskite ◽  
Entropy Change ◽  
Solid State Reaction Method ◽  
Cooling Power ◽  
X Ray Diffraction ◽  
Site Disorder ◽  
Magnetocaloric Properties ◽  
Arrott Plots

The crystal structure, magnetic and magnetocaloric properties of the Sr2FeMo1–xNbxO6 (0 ≤ x ≤ 0.3) samples prepared by solid state reaction method were investigated using X-ray diffraction (XRD) and magnetic measurements. The room temperature XRD profiles obtained for all the samples revealed the formation of the double perovskite tetragonal structure with I4/mmm symmetry. Maximum values of spontaneous magnetization (17.6 emu/g at 150 K) and Curie temperature, TC (380 K) were observed in the Sr2FeMo0.9Nb0.1O6 sample indicating that low Niobium (Nb) substitution (x = 0.1) at the Mo site in the host material resulted in higher magnetization and TC. Lower values of magnetization and TC were recorded in the samples with higher Nb concentration (x = 0.2, 0.3) that was attributed to the decrease in orbital hybridization and increase in anti-site disorder resulting from heavy doping. A second order of the magnetic phase transition in each sample was confirmed by the magnetization measurements and Arrott plots. The maximum magnetic entropy change and relative cooling power (RCP) were enhanced in lowest Nb doped sample (x = 0.1) suggesting that this compound can be used in magnetic refrigeration technology.

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