The Influence of Oleic Acid to Metal Nitrate Ratio on the Particle Size and Magnetic Properties of Lanthanum Ferrite Nanoparticles by Emulsion Method

The crystalline nanoparticles of Ni0.2Zn0.8Fe2O4 ferrite were synthesized by chemical co-precipitation with precursor concentration of 0.1M, then modified by 0.25M solution of oleic acid in pentanol, finally heated at temperatures 120, 140, 160 and 180oC for 6h in autoclave. The XRD, EDS and TEM confirmed that all of samples are crystalline and their particle size are 6, 6.5, 7 and 8 nm. The magnetic properties showed that the coercive force, the remanence of samples are about zero, the saturation magnetization Ms has values from 14.20 to 27.12 emu/g.

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Hydrothermal Synthesis of CoFe2O4 Nanoparticles and their Magnetic Properties

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.821-822.1358 ◽

2013 ◽

Vol 821-822 ◽

pp. 1358-1361 ◽

Cited By ~ 2

Author(s):

Fan Zhang ◽

Rui Liang Su ◽

Li Zhi Shi ◽

Yang Liu ◽

Yan Na Chen ◽

...

Keyword(s):

Particle Size ◽

Magnetic Properties ◽

Room Temperature ◽

Magnetic Measurements ◽

Spinel Ferrite ◽

Synthesis Method ◽

Ferrite Nanoparticles ◽

Particle Sizes ◽

Naoh Solution ◽

20 Nm

CoFe2O4 (CFO) nanoparticles was synthesized by a simple hydrothermal method using NaOH solution as a mineralizer at 200 °C for 4 h. It was found that CFO particle sizes decreased firstly and then increased with the increasing of NaOH concentration, and had a minumum value about 10-20 nm when selected 4 mol/L NaOH solution, indicating the NaOH concentration played an important role in controlling the particle size of CFO powders. The room temperature magnetic measurements showed that the saturation magnetization value was 48 emu/g, which is less than the bulk value. The synthesis method is possible to be a general approach for the preparation of other spinel ferrite nanoparticles.

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Highly dispersed spinel (Mg, Ca, Ba)-ferrite nanoparticles: Tuning the particle size and magnetic properties through a modified polyacrylamide gel route

Ceramics International ◽

10.1016/j.ceramint.2016.09.075 ◽

2016 ◽

Vol 42 (16) ◽

pp. 19133-19140 ◽

Cited By ~ 17

Author(s):

S.F. Wang ◽

X.T. Zu ◽

G.Z. Sun ◽

D.M. Li ◽

C.D. He ◽

...

Keyword(s):

Particle Size ◽

Magnetic Properties ◽

Ferrite Nanoparticles ◽

Polyacrylamide Gel ◽

Polyacrylamide Gel Route ◽

Highly Dispersed ◽

Modified Polyacrylamide

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Zero-Dimensional Graphene and Its Behavior under Mechanochemical Activation with Zinc Ferrite Nanoparticles

MRS Advances ◽

10.1557/adv.2019.400 ◽

2019 ◽

Vol 5 (33-34) ◽

pp. 1731-1737 ◽

Cited By ~ 1

Author(s):

Monica Sorescu ◽

Matthew Knauss ◽

Alice Perrin ◽

Michael McHenry

Keyword(s):

Magnetic Field ◽

Particle Size ◽

Magnetic Properties ◽

Isomer Shift ◽

Ball Milling ◽

Quadrupole Splitting ◽

Applied Magnetic Field ◽

Zinc Ferrite ◽

Mechanochemical Activation ◽

Ferrite Nanoparticles

ABSTRACTEquimolar mixtures of zero-dimensional graphene (SkySpring Nanomaterials, 1-5 nm particle size) and zinc ferrite nanoparticles (Alfa Aesar, 50 nm particle size) were exposed to mechanochemical activation by high-energy ball milling for time intervals of 0-12 hours. Their structural and magnetic properties were analyzed by Mӧssbauer spectroscopy and magnetic measurements. The spectra of zinc ferrite milled without graphene were fitted with one quadrupole-split doublet (quadrupole splitting 0.5 mm/s, isomer shift 0.23 mm/s) and indicated that zinc ferrite was superparamagnetic. The line width of the doublet increased from 0.41 to 0.64 mm/s, which correlates with a reduction in particle size as effect of the ball milling processing performed. When graphene was added to the milling powders, the Mӧssbauer spectra showed the appearance of another quadrupole doublet, with a quadrupole splitting of 0.84 mm/s and an isomer shift of -0.38 mm/s. Its abundance to the spectrum remained constant to 4.48% while the milling time was increased. This second doublet could be related to carbon atoms occupying neighborhoods in the proximity of iron atoms. Hysteresis loops were recorded in an applied magnetic field of 5 T at a temperature of 5 K. A change in the approach to saturation of the loop was observed, with saturation being achieved for the sample milled for 12 hours with graphene. Zero-field-cooling-field-cooling (ZFC-FC) was performed on all samples between 5-300 K with an applied magnetic field of 200 Oe. Graphene was found to stabilize the magnetic properties of the milled system of powders to a blocking temperature of about 90 K.

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Effect of Milling in Various Media and Annealing on the Structure and Magnetic Properties of Strontium Hexaferrite Powder

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.190.183 ◽

2012 ◽

Vol 190 ◽

pp. 183-187 ◽

Cited By ~ 2

Author(s):

S.V. Ketov ◽

E.A. Lopatina ◽

T.A. Bulatov ◽

Yu.D. Yagodkin ◽

V.P. Menushenkov

Keyword(s):

Particle Size ◽

Magnetic Properties ◽

Oleic Acid ◽

Milling Time ◽

Strontium Hexaferrite ◽

Powder Particle Size ◽

Nanocrystalline State ◽

Abrupt Decrease ◽

Phase Type ◽

Crystallite Sizes

In the present work, the structure and magnetic properties of strontium hexaferrite powder during milling in various media and subsequent annealing were studied. The milling of the powder leads to an abrupt decrease in the powder particle size and the average crystallite sizes as well as an increase in lattice microstrains of the SrFe12O19 phase. During milling in toluene, no changes in the phase composition were observed, whereas, during milling in water, the Fe2O3 phase (type H1.1) is formed. In the powder milled in oleic-acid-containing toluene a small quantity of α-Fe was found. After milling, the saturation magnetization and remanence decrease; at the same time, the coercive force of the powder milled in toluene is unchanged with increasing milling time, but slightly increases after milling in water and in oleic-acid-containing toluene. The annealing allowed us to increase the magnetic properties of the powder. It is conditioned by formation of nanocrystalline state. Moreover, the magnetic properties values depend on the medium and time of milling. The annealed powders are characterized by the following magnetic properties: μ0Нci = 0.42 ÷ 0.49 T, Br = 0.23 ÷ 0.24 T, (BH)max = 8-9.6 kJ/m3.

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