Magnetic and optical properties of ionic ferrofluids based on nickel ferrite nanoparticles

Hasmonay, E.; Depeyrot, J.; Sousa, Marcelo Henrique; Tourinho, F.A.; Bacri, Jean‐Claude; Perzynski, R.; Raǐkher, Yu. L.; Rośenman, I.

doi:10.1063/1.1288016

Cited by 95 publications

(49 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Such particles are generally termed as the core-shell nanoparticles, where the core spins behave like ferromagnetic or ferrimagnetic, and the shell is composed of disordered or canted spins. Hasmonay et al [9] and Jaing et al [10] explained the observed decrease in the saturation magnetization of NiFe 2 O 4 nanoparticles with the reduction in particle size on the basis of core-shell morphology and the surface effects arising from the noncollinearity of the magnetic moments on the surface, respectively. Later, Š epelák et al [11] and Jacob and Abdul [12] found that the nanostructured NiFe 2 O 4 sample having the lower grain size showed structural deviation from inverse spinel to mixed spinel structure as a result of interchange of cations between the A-and B-sites.…”

Section: Introductionmentioning

confidence: 97%

Cation distribution and enhanced surface effects on the temperature-dependent magnetization of as-prepared NiFe2O4 nanoparticles

Nadeem

Siddique

2015

Appl. Phys. A

View full text Add to dashboard Cite

Nickel ferrite, i.e., NiFe 2 O 4 , nanoparticles are synthesized by sol-gel method using urea as a neutralizing agent. The formation of spinel phase and crystal structure of the as-prepared sample is analyzed by X-ray diffraction and transmission electron microscope. In order to confirm phase formation and cation arrangement, room temperature 57 Fe Mössbauer spectroscopy is employed. The degree of inversion (i) estimated from the relative peak area is found to be 0.6, which confirms a mixed spinel structure of the asprepared sample. Zero-field-cooled/field-cooled measurements showed evidence of superparamagnetic behavior associated with the nanosized particles. Hysteresis loop measurements revealed temperature-dependent magnetic properties: The coercive field (H C ) decreases with increasing temperature and deviates from the Kneller's law for ferromagnetic nanostructures; and the saturation magnetization (M s ) follows modified Bloch's law in the temperature range between 25 and 400 K. However, below 25 K, an abrupt increase in magnetization of nanoparticles is observed. In order to understand this behavior, an additional contribution has to be added to the core magnetization to properly fit the data. Hence, a surface correction term to the Bloch's law is found to describe the temperature dependence of magnetization in the core-shell NiFe 2 O 4 nanoparticles.

show abstract

Section: Introductionmentioning

confidence: 97%

Cation distribution and enhanced surface effects on the temperature-dependent magnetization of as-prepared NiFe2O4 nanoparticles

Nadeem

Siddique

2015

Appl. Phys. A

View full text Add to dashboard Cite

show abstract

“…NiFe 2 O 4 finds various applications such as gas-sensor, magneticfluids, catalysts, magnetic storage systems, photomagnetic materials, magnetic resonance imaging [1][2][3][4][5][6]. Various methods have been established to prepare NiFe 2 O 4 nanoparticles, such as sol-gel method, reverse micelle, polymer assisted co-precipitation method, shock wave synthesis, combustion reaction, sonochemical process, hydrothermal methods, polymer-pyrolysis method, citrate precursor techniques and reverse micro emulsion process [7][8][9][10][11][12][13][14][15][16][17][18].…”

Section: Introductionmentioning

confidence: 99%

Synthesis and study of magnetic properties of NiFe2O4 nanoparticles by PVA assisted auto-combustion method

Sivakumar¹,

Ramesh

Ramanand³

et al. 2011

J Mater Sci: Mater Electron

View full text Add to dashboard Cite

NiFe 2 O 4 nanoparticles are prepared by a simple and cost-effective method using via polyvinyl alcohol assisted sol-gel auto-combustion method. The X-ray diffraction result indicated that the synthesized nanoparticles have only the inverse spinel structure without the presence of any other phase impurities. HR-SEM and TEM images showed that the particles are spherical shape with particle size in the range *11 nm. The magnetic property of these nanoparticles is studied for the enlightening ferrimagnetic behaviour at room temperature. The value of the magnetic saturation (M s ) is 44.3 emug -1 , remanent magnetization (M r ) is 19.8 emug -1 and coercive force (H c ) is 672.02 Oe.

show abstract

“…the apparent M f.s could be less than ϕ v M p.s , or M f.s /ϕ v < M p.s , 6,12 where M f.s /ϕ v is termed the reduced magnetization of the ferrofluids and presents the effective magnetization of the solid phase. 13 For surface ferrofluids, this loss is assumed to arise from a chemical reaction between the surfactant and ferrite nanoparticles, but no structural or magnetic evidence exists to confirm this hypothesis. 6 Though it has been known that the spins in the surface being canted or the spins close to the surface to be pinned by surfactant molecules would result in the less saturation magnetization of nanoparticles M p.s than that of the bulk M b.s , 14,15 the arising of loss in ferrofluid magnetization is still no clear due to experimental diffcult.…”

Section: Introductionmentioning

confidence: 99%

Investigation into loss in ferrofluid magnetization

Gong

Lin

et al. 2014

AIP Advances

View full text Add to dashboard Cite

Ferrofluids containing γ-Fe2O3/Ni2O3 nanoparticles (not chemically treated) were synthesized using water and mixed water–glycerol as carrier liquid and the ferrofluid viscosity was modified by varying the glycerol content in the carrier liquid. The apparent magnetization of the ferrofluids decreased with increasing glycerol content. The loss in magnetization is described by the ratio of effective magnetic volume fraction to physical volume fraction of nanoparticles in the ferrofluids as a characteristic parameter. We ascribe the loss to the formation of “dead aggregates” having a ring-like structure of closed magnetic flux rather than to any chemical reaction. Such dead aggregates exist in zero magnetic field and do not contribute to the magnetization in the low or high field regime, so that the effective magnetic volume fraction in the ferrofluids decrease. An increase in carrier liquid viscosity is similar to a weakening of the thermal effect, so the number of dead aggregates increases and the magnetization decreases in inverse proportion to the viscosity. This relationship between the apparent magnetization and ferrofluid carrier liquid viscosity can be termed the “viscomagnetic effect”.

show abstract

Magnetic and optical properties of ionic ferrofluids based on nickel ferrite nanoparticles

Cited by 95 publications

References 23 publications

Cation distribution and enhanced surface effects on the temperature-dependent magnetization of as-prepared NiFe2O4 nanoparticles

Cation distribution and enhanced surface effects on the temperature-dependent magnetization of as-prepared NiFe2O4 nanoparticles

Synthesis and study of magnetic properties of NiFe2O4 nanoparticles by PVA assisted auto-combustion method

Investigation into loss in ferrofluid magnetization

Contact Info

Product

Resources

About