Controllable synthesis of Co1−x MxFe2O4 nanoparticles (M = Zn, Cu, and Mn; x = 0.0 and 0.5) by cost-effective sol–gel approach: analysis of structure, elastic, thermal, and magnetic properties

The copper (Cu) substitution in barium hexaferrite (BaFe12O19) crystals from the sol-gel auto-combustion synthesis is demonstrated as a cost-effective pathway to achieve alterable magnetic properties. Subsequent heat treatments at 450 °C and 1050 °C result in irregularly shaped nanoparticles characterized as the M-type BaFe12O19 with the secondary phase of hematite (α-Fe2O3). Despite the mixed phase, the substantial coercivity of 2626 Oe and magnetization as high as 74.8 emu/g are obtained in this undoped ferrite. The copper (Cu) doing strongly affects morphology and magnetic properties of BaFe12−xCuxO19 (x = 0.1, 0.3, and 0.5). The majority of particles become microrods for x = 0.1 and microplates in the case of x = 0.3 and 0.5. The coercivity and magnetization tend to reduce as Cu2+ increasingly substitutes Fe3+. From these findings, magnetic properties for various applications in microwave absorbers, recording media, electrodes, and permanent magnets can be tailored by the partial substitution in hexaferrite crystals.

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

Nanoscience &Nanotechnology-Asia ◽

10.2174/2210681208666181018093813 ◽

2020 ◽

Vol 10 (2) ◽

pp. 152-156 ◽

Cited By ~ 1

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.

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Effect of Annealing temperature on the Structural and Magnetic Properties of TbxY3-xFe5O12(x = 0.0, 1.0, 2.0) Thin Films Prepared by Sol-Gel Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.501.236 ◽

2012 ◽

Vol 501 ◽

pp. 236-241 ◽

Cited By ~ 1

Author(s):

Ftema W. Aldbea ◽

Noor Bahyah Ibrahim ◽

Mustafa Hj. Abdullah ◽

Ramadan E. Shaiboub

Keyword(s):

Thin Films ◽

Magnetic Properties ◽

Room Temperature ◽

Annealing Temperature ◽

Sol Gel ◽

Vibrating Sample Magnetometer ◽

X Ray ◽

Garnet Phase ◽

Sol Gel Process ◽

Amorphous Structures

Thin films nanoparticles TbxY3-xFe5O12 (x=0.0, 1.0, 2.0) were prepared by the sol-gel process followed by annealing process at various annealing temperatures of 700° C, 800° C and 900° C in air for 2 h. The results obtained from X-ray diffractometer (XRD) show that the films annealed below 900°C exhibit peaks of garnet mixed with small amounts of YFeO3 and Fe2O3. Pure garnet phase has been detected in the films annealed at 900°C. Before annealing the films show amorphous structures. The particles sizes measurement using the field emission scanning electron microscope (FE-SEM) showed that the particles sizes increased as the annealing temperature increased. The magnetic properties were measured at room temperature using the vibrating sample magnetometer (VSM). The saturation magnetization (Ms) of the films also increased with the annealing temperature. However, different behavior of coercivity (Hc) has been observed as the annealing temperature was increased.

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Elucidation of the Crystal Growth Characteristics of SnO2 Nanoaggregates Formed by Sequential Low-Temperature Sol-Gel Reaction and Freeze Drying

Nanomaterials ◽

10.3390/nano11071738 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1738

Author(s):

Saeid Vafaei ◽

Alexander Wolosz ◽

Catlin Ethridge ◽

Udo Schnupf ◽

Nagisa Hattori ◽

...

Keyword(s):

Crystal Growth ◽

Low Temperature ◽

Photoelectron Spectroscopy ◽

High Performance ◽

Freeze Drying ◽

Sno2 Nanoparticles ◽

Sol Gel ◽

Functional Materials ◽

Cost Effective ◽

High Concentration

SnO2 nanoparticles are regarded as attractive, functional materials because of their versatile applications. SnO2 nanoaggregates with single-nanometer-scale lumpy surfaces provide opportunities to enhance hetero-material interfacial areas, leading to the performance improvement of materials and devices. For the first time, we demonstrate that SnO2 nanoaggregates with oxygen vacancies can be produced by a simple, low-temperature sol-gel approach combined with freeze-drying. We characterize the initiation of the low-temperature crystal growth of the obtained SnO2 nanoaggregates using high-resolution transmission electron microscopy (HRTEM). The results indicate that Sn (II) hydroxide precursors are converted into submicrometer-scale nanoaggregates consisting of uniform SnO2 spherical nanocrystals (2~5 nm in size). As the sol-gel reaction time increases, further crystallization is observed through the neighboring particles in a confined part of the aggregates, while the specific surface areas of the SnO2 samples increase concomitantly. In addition, X-ray photoelectron spectroscopy (XPS) measurements suggest that Sn (II) ions exist in the SnO2 samples when the reactions are stopped after a short time or when a relatively high concentration of Sn (II) is involved in the corresponding sol-gel reactions. Understanding this low-temperature growth of 3D SnO2 will provide new avenues for developing and producing high-performance, photofunctional nanomaterials via a cost-effective and scalable method.

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Defects induced tailored optical and magnetic properties of Zn-doped CeO2 nanoparticles synthesized by a facile sol-gel type process

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2021.160149 ◽

2021 ◽

pp. 160149

Author(s):

B. Soni ◽

S. Makkar ◽

S. Biswas

Keyword(s):

Magnetic Properties ◽

Sol Gel ◽

Ceo2 Nanoparticles ◽

Type Process ◽

Optical And Magnetic Properties ◽

Doped Ceo2

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Structural and magnetic properties of Mn doped cobalt ferrite nanoparticles synthesized by Sol-Gel auto combustion method

Materials Today Proceedings ◽

10.1016/j.matpr.2021.04.209 ◽

2021 ◽

Author(s):

C. Joseph Prabagar ◽

S. Anand ◽

M. Asisi Janifer ◽

S. Pauline

Keyword(s):

Magnetic Properties ◽

Cobalt Ferrite ◽

Sol Gel ◽

Combustion Method ◽

Ferrite Nanoparticles ◽

Cobalt Ferrite Nanoparticles ◽

Auto Combustion ◽

Structural And Magnetic Properties ◽

Mn Doped

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

Main Group Metal Chemistry ◽

10.1515/mgmc-2020-0004 ◽

2020 ◽

Vol 43 (1) ◽

pp. 26-42 ◽

Cited By ~ 2

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.

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The Study of Magnetic Properties for Non-Magnetic Ions Doped BiFeO3

Materials ◽

10.3390/ma14154061 ◽

2021 ◽

Vol 14 (15) ◽

pp. 4061

Author(s):

Yongtao Li ◽

Liqing Liu ◽

Dehao Wang ◽

Hongguang Zhang ◽

Xuemin He ◽

...

Keyword(s):

Magnetic Properties ◽

Local Structure ◽

Metal Ion ◽

Single Phase ◽

Sol Gel ◽

X Ray ◽

Co Doping ◽

Magnetic Ions ◽

X Ray Absorption ◽

Fe Ions

BiFeO3 is considered as a single phase multiferroic. However, its magnetism is very weak. We study the magnetic properties of BiFeO3 by Cu and (Cu, Zn). Polycrystalline samples Bi(Fe0.95Cu0.05)O3 and BiFe0.95(Zn0.025Cu0.025)O3 are prepared by the sol-gel method. The magnetic properties of BiFe0.95(Zn0.025Cu0.025)O3 are greater than that of BiFeO3 and Bi(Fe0.95Cu0.05)O3. The analyses of X-ray absorption fine structure data show that the doped Cu atoms well occupy the sites of the Fe atoms. X-ray absorption near edge spectra data confirm that the valence state of Fe ions does not change. Cu and Zn metal ion co-doping has no impact on the local structure of the Fe and Bi atoms. The modification of magnetism by doping Zn can be understood by the view of the occupation site of non-magnetically active Zn2+.

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