scholarly journals Exchange-Coupling Behavior in SrFe12O19/La0.7Sr0.3MnO3 Nanocomposites

Ceramics ◽  
2019 ◽  
Vol 2 (1) ◽  
pp. 100-111 ◽  
Author(s):  
Jiba Nath Dahal ◽  
Dipesh Neupane ◽  
Sanjay R. Mishra
Keyword(s):  
Magnetic Properties ◽  
Saturation Magnetization ◽  
Exchange Coupling ◽  
Synthesis Method ◽  
Temperature Hysteresis ◽  
One Pot ◽  
Simple Method ◽  
Soft Phase ◽  
Squareness Ratio ◽  
Auto Combustion

Magnetically hard-soft (100-x) SrFe12O19–x wt % La0.7Sr0.3MnO3 nanocomposites were synthesized via a one-pot auto-combustion technique using nitrate salts followed by heat treatment in air at 950 °C. X-ray diffraction (XRD), transmission electron microscopy (TEM), and vibrating sample magnetometry (VSM) were used to characterize the structural and magnetic properties of the samples. XRD spectra revealed the formation of a mixture of ferrite and magnetite phases without any trace of secondary phases in the composite. Microstructural images show the proximity grain growth of both phases. The room temperature hysteresis loops of the samples showed the presence of exchange-coupling between the hard and soft phases of the composite. Although saturation magnetization reduced by 41%, the squareness ratio and coercivity of the nanocomposite improved significantly up to 6.6% and 81.7%, respectively, at x = 40 wt % soft phase content in the nanocomposite. The enhancement in squareness ratio and coercivity could be attributed to the effective exchange-coupling interaction, while the reduction in saturation magnetization could be explained on the basis of atomic intermixing between phases in the system. Overall, these composite particles exhibited magnetically single-phase behavior. The adopted synthesis method is low cost and rapid and results in pure crystalline nanocomposite powder. This simple method is a promising way to tailor and enhance the magnetic properties of oxide-based hard-soft magnetic nanocomposites.

scholarly journals Synthesis of novel hard/soft ferrite composites particles with improved magnetic properties and exchange coupling

2018 ◽  
Vol 12 (3) ◽  
pp. 248-256 ◽  
Author(s):  
Faezeh Tavakolinia ◽  
Mohammad Yousefi ◽  
Seyyed Afghahi ◽  
Saeid Baghshahi ◽  
Susan Samadi
Keyword(s):  
Magnetic Properties ◽  
Exchange Coupling ◽  
Sol Gel ◽  
Phase Behaviour ◽  
Composite Particles ◽  
One Pot ◽  
Soft Phase ◽  
Auto Combustion ◽  
Physical Mixing ◽  
Soft Ferrite

SrFe12O19/Zn0.4Co0.2Ni0.4Fe2O4 hard/soft ferrite composite particles with 20, 40, 60 and 80 wt.% of soft phase were prepared by one-pot sol-gel auto-combustion and physical mixing methods. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) and vibrating sample magnetometer (VSM) were used to characterize the structural and magnetic properties of the samples. XRD spectrum revealed the formation of mixed ferrite phases in the composite particles. The hysteresis loops of the samples showed the presence of exchange coupling between the hard and soft ferrites. The composite particles with 20 and 60 wt.% of the soft phase demonstrated the highest Mr/Ms ratio, i.e. 0.29 and 0.28, respectively. In addition, the highest Ms, Mr and Hc were achieved in the composite particles with 40, 60 and 20 wt.% of the soft phase, respectively. Compared to the physical mixing method (PM), the composite particles prepared by the sol-gel auto-combustion method (OP) demonstrated better magnetic properties. The exchange coupling interaction between the hard and soft ferrite phases was similar in both methods. These composite particles exhibited magnetically single phase behaviour, however, the saturation magnetization was lower in the physical mixing pared to that of the one-pot method.

Structural, Morphological and Magnetic Characterization of Sm-substituted Ni-Zn Ferrite

2020 ◽  
Vol 10 (2) ◽  
pp. 152-156 ◽  
Author(s):  
Muhammad Hanif bin Zahari ◽  
Beh Hoe Guan ◽  
Lee Kean Chuan ◽  
Afiq Azri bin Zainudin
Keyword(s):  
Magnetic Properties ◽  
Rare Earth ◽  
Saturation Magnetization ◽  
Sol Gel ◽  
Magnetic Behavior ◽  
Rare Earth Ions ◽  
Ion Concentration ◽  
Zn Ferrite ◽  
Auto Combustion ◽  
Combustion Technique

Background: Rare earth materials are known for its salient electrical insulation properties with high values of electrical resistivity. It is expected that the substitution of rare earth ions into spinel ferrites could significantly alter its magnetic properties. In this work, the effect of the addition of Samarium ions on the structural, morphological and magnetic properties of Ni0.5Zn0.5SmxFe2-xO4 (x=0.00, 0.02, 0.04, 0.06, 0.08, 0.10) synthesized using sol-gel auto combustion technique was investigated. Methods: A series of Samarium-substituted Ni-Zn ferrite nanoparticles (Ni0.5Zn0.5SmxFe2-xO4 where x=0.00, 0.02, 0.04, 0.06, 0.08, 0.10) were synthesized by sol-gel auto-combustion technique. Structural, morphological and magnetic properties of the samples were examined through X-Ray Diffraction (XRD), Field-Emission Scanning Electron Microscope (FESEM) and Vibrating Sample Magnetometer (VSM) measurements. Results: XRD patterns revealed single-phased samples with spinel cubic structure up to x= 0.04. The average crystallite size of the samples varied in the range of 41.8 – 85.6 nm. The prepared samples exhibited agglomerated particles with larger grain size observed in Sm-substituted Ni-Zn ferrite as compared to the unsubstituted sample. The prepared samples exhibited typical soft magnetic behavior as evidenced by the small coercivity field. The magnetic saturation, Ms values decreased as the Sm3+ concentration increases. Conclusion: The substituted Ni-Zn ferrites form agglomerated particles inching towards more uniform microstructure with each increase in Sm3+ substitution. The saturation magnetization of substituted samples decreases with the increase of samarium ion concentration. The decrease in saturation magnetization can be explained based on weak super exchange interaction between A and B sites. The difference in magnetic properties between the samples despite the slight difference in Sm3+ concentrations suggests that the properties of the NiZnFe2O4 can be ‘tuned’, depending on the present need, through the substitution of Fe3+ with rare earth ions.

scholarly journals Green synthesis and characterization of hexaferrite strontium-perovskite strontium photocatalyst nanocomposites

2020 ◽  
Vol 43 (1) ◽  
pp. 26-42 ◽  
Author(s):  
Zahra Hajian Karahroudi ◽  
Kambiz Hedayati ◽  
Mojtaba Goodarzi
Keyword(s):  
Magnetic Properties ◽  
Green Synthesis ◽  
Sol Gel ◽  
Synthesis Method ◽  
Combustion Method ◽  
Lemon Juice ◽  
X Ray Diffraction ◽  
X Ray ◽  
Auto Combustion

AbstractThis study presents a preparation of SrFe12O19– SrTiO3 nanocomposite synthesis via the green auto-combustion method. At first, SrFe12O19 nanoparticles were synthesized as a core and then, SrTiO3 nanoparticles were prepared as a shell for it to manufacture SrFe12O19–SrTiO3 nanocomposite. A novel sol-gel auto-combustion green synthesis method has been used with lemon juice as a capping agent. The prepared SrFe12O19–SrTiO3 nanocomposites were characterized by using several techniques to characterize their structural, morphological and magnetic properties. The crystal structures of the nanocomposite were investigated via X-ray diffraction (XRD). The morphology of SrFe12O19– SrTiO3 nanocomposite was studied by using a scanning electron microscope (SEM). The elemental composition of the materials was analyzed by an energy-dispersive X-ray (EDX). Magnetic properties and hysteresis loop of nanopowder were characterized via vibrating sample magnetometer (VSM) in the room temperature. Fourier transform infrared spectroscopy (FTIR) spectra of the samples showed the molecular bands of nanoparticles. Also, the photocatalytic behavior of nanocomposites has been checked by the degradation of azo dyes under irradiation of ultraviolet light.

Structural, morphological and magnetic properties of Mn2+ ions substituted nanosized nickel–copper–cobalt ferrites through sol–gel auto-combustion method

2019 ◽  
Vol 34 (01) ◽  
pp. 2050002
Author(s):  
Wei Zhang ◽  
Aimin Sun ◽  
Xiqian Zhao ◽  
Xiaoguang Pan ◽  
Yingqiang Han
Keyword(s):  
Magnetic Properties ◽  
Saturation Magnetization ◽  
Spinel Structure ◽  
Remanent Magnetization ◽  
Cobalt Ferrite ◽  
Sol Gel ◽  
Combustion Method ◽  
Magnetic Data ◽  
Nickel Copper ◽  
Auto Combustion

Manganese substituted nickel–copper–cobalt ferrite nanoparticles having the basic composition [Formula: see text] (x = 0.0, 0.1, 0.2, 0.3 and 0.4) were synthesized by sol–gel auto-combustion method. X-ray diffraction (XRD) was used to estimate phase purity and lattice symmetry. All the prepared samples show the single-phase cubic spinel structure. Fourier transform infrared (FTIR) measurements also confirm the cubic spinel structure of the ferrite that is formed. The preparation of samples show these nearly spherical particles by Transmission electron microscopy (TEM). The magnetic properties of Mn[Formula: see text] ion substituted in nickel–copper–cobalt ferrite were studied by Vibrating sample magnetometer (VSM). The saturation magnetization ([Formula: see text]), remanent magnetization [Formula: see text], coercivity [Formula: see text], magnetic moment [Formula: see text] and anisotropy constant [Formula: see text] first increase and then decrease with the increase of [Formula: see text] ions content. They had better magnetism than pure sample and other substituted samples when the substitution amount of [Formula: see text] ions was [Formula: see text]. At [Formula: see text], the maximum values of remanent magnetization [Formula: see text], saturation magnetization [Formula: see text] and coercivity [Formula: see text] are 25.58 emu/g, 61.95 emu/g and 689.76 Oe, respectively. This indicates that the magnetism of ferrite can improve by substituting with the appropriate amount of manganese. However, due to the excess [Formula: see text] ions instead, ferrite magnetism is weakened. This means that these materials can be used in magnetic data storage and recording media.

scholarly journals Green Synthesis of Co-Zn Spinel Ferrite Nanoparticles: Magnetic and Intrinsic Antimicrobial Properties

Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 5014
Author(s):  
Alexander Omelyanchik ◽  
Kateryna Levada ◽  
Stanislav Pshenichnikov ◽  
Maryam Abdolrahim ◽  
Miran Baricic ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Magnetic Nanoparticles ◽  
Chemical Composition ◽  
Saturation Magnetization ◽  
Cobalt Ferrite ◽  
Spinel Ferrite ◽  
Ferrite Nanoparticles ◽  
Ferromagnetic Behavior ◽  
Wide Range ◽  
Auto Combustion

Spinel ferrite magnetic nanoparticles have attracted considerable attention because of their high and flexible magnetic properties and biocompatibility. In this work, a set of magnetic nanoparticles of cobalt ferrite doped with zinc was synthesized via the eco-friendly sol-gel auto-combustion method. Obtained particles displayed a room-temperature ferromagnetic behavior with tuned by chemical composition values of saturation magnetization and coercivity. The maximal values of saturation magnetization ~74 Am2/kg were found in cobalt ferrite nanoparticles with a 15–35% molar fraction of cobalt replaced by zinc ions. At the same time, the coercivity exhibited a gradually diminishing trend from ~140 to ~5 mT whereas the concentration of zinc was increased from 0 to 100%. Consequently, nanoparticles produced by the proposed method possess highly adjustable magnetic properties to satisfy the requirement of a wide range of possible applications. Further prepared nanoparticles were tested with bacterial culture to display the influence of chemical composition and magnetic structure on nanoparticles-bacterial cell interaction.

scholarly journals The effects of the thickness of magnetically hard- and soft-phase layers on magnetic properties and exchange coupling in multilayer magnets

2005 ◽  
Vol 97 (10) ◽  
pp. 10K303 ◽  
Author(s):  
W. Liu ◽  
Y. C. Sui ◽  
J. Zhou ◽  
X. K. Sun ◽  
C. L. Chen ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Exchange Coupling ◽  
Soft Phase ◽  
Phase Layers ◽  
Magnetically Hard

Preparation and Magnetic Properties of La Substituted Barium Ferrites Synthesized by the Oxide one Pot Synthesis (OOPS) Process

2013 ◽  
Vol 634-638 ◽  
pp. 2250-2253 ◽  
Author(s):  
Sitthisak Sorlateap ◽  
Wirunya Keawwattana
Keyword(s):  
Magnetic Properties ◽  
Saturation Magnetization ◽  
Crystalline Structure ◽  
Coercive Field ◽  
Barium Ferrite ◽  
One Pot ◽  
Xrd Pattern ◽  
One Pot Synthesis ◽  
Ferrite Structure ◽  
Barium Ferrites

Lanthanum (La) substituted barium ferrite, Ba1-xLaxFe12O19(x=0.00-0.40) has been synthesized by the oxide one pot synthesis (OOPS) process. The crystalline structure and magnetic properties have been investigated by means of XRD, SEM and VSM. The XRD pattern matched with the barium ferrite structure. The saturation magnetization (Ms) and coercive field (Hc) of ferrites increased by substitution of La ions on Ba sites at the content up to x=0.15 and then decrease.

Ag2S–CoS2 hetero-nanostructures: One-pot colloidal synthesis and improved magnetic properties

2014 ◽  
Vol 07 (03) ◽  
pp. 1450024 ◽  
Author(s):  
Yuanjun Liu ◽  
Aihua Yuan ◽  
Guoxing Zhu ◽  
Chunlin Bao ◽  
Rongxian Zhang ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Transition Temperature ◽  
Saturation Magnetization ◽  
Magnetic Materials ◽  
Superionic Conductor ◽  
Colloidal Synthesis ◽  
One Pot ◽  
Chemical Route

Ag 2 S – CoS 2 hetero-nanostructures with well defined and sharp hetero-interface were synthesized with a simple one-pot colloidal chemical route. It is proposed that the Ag 2 S nanoparticles with superionic conductor properties play a catalyst role inducing the growth of CoS 2. The magnetic properties of the Ag 2 S – CoS 2 hetero-nanostructures were investigated, which gives a saturation magnetization of 8.3 emu/g at 1.8 K and transition temperature of 120 K. It is believed that the reported results would give some hints to the development of multifunction magnetic materials.

Sign in / Sign up

Export Citation Format

Share Document