Magnetic and structural properties of nano sized Dy-doped cobalt ferrite synthesized by co-precipitation

Karimi, Z.; Mohammadifar, Yaghoub; Shokrollahi, H.; Asl, Sh. Khameneh; Yousefi, Gholamhossein; Karimi, Loghman

doi:10.1016/j.jmmm.2014.01.016

Cited by 212 publications

(49 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…As seen in Table 1 s) and the bond angles (θ 1 , θ 2 , θ 3 , θ 4 , and θ 5 ) between the cations and cation-anion, Fig. 3, are given by the following relations [21]:…”

Section: Structural and Microstructure Analysismentioning

confidence: 99%

“…The angles θ 1 , θ 2 , and θ 5 suggest the strengthening of the A-B and A-A interactions, while the decrease in θ 3 and θ 4 indicates the weakening of the B-B interaction in the system. Generally in ferrimagnetic materials, the increase in A-B (θ 1 and θ 2 angles) enhances the super-exchange strength [21]. As Zn 2+ ions substitute nickel, the situation is reversed; A-B (θ 1 and θ 2 angles) decreases; hence, super-exchange strength decreases.…”

Section: Me-omentioning

confidence: 99%

See 1 more Smart Citation

Synthesis and Characterization of Ultrasmall Nanocrystalline Zn-substituted Ni-Sm-Ga Ferrites

Yehia

Ismail

Mohamed

2015

J Supercond Nov Magn

View full text Add to dashboard Cite

Ultrasmall nanocrystalline NiSm 0.01 Fe 1.99 O 4 and Ni 1−x Zn x Sm 0.01 Ga 0.5 Fe 1.49 O 4 (x = 0.0, 0.3, 0.5) ferrites were synthesized by sol-gel method. The effect of Ga and Zn substitution on the particle size and structural and magnetic properties was investigated using X-ray diffraction patterns (XRD), transmission electron microscope (TEM), Mössbauer effect spectroscopy (ME), and vibrating sample magnetometer (VSM) techniques. XRD measurements suggest the formation of single-phase spinel ferrites with ultrasmall particles size ranging from 4 to 8 nm. Mössbauer effect measurements show a clear signature of superparamagnetism in the studied samples, where the reduced particle size causes the broadening of the Mössbauer spectra and the presence of a pronounced central doublet in all the measured samples. VSM measurements show a strong reduction of saturation magnetization due to size effects.

show abstract

“…As seen in Table 1 s) and the bond angles (θ 1 , θ 2 , θ 3 , θ 4 , and θ 5 ) between the cations and cation-anion, Fig. 3, are given by the following relations [21]:…”

Section: Structural and Microstructure Analysismentioning

confidence: 99%

Section: Me-omentioning

confidence: 99%

Synthesis and Characterization of Ultrasmall Nanocrystalline Zn-substituted Ni-Sm-Ga Ferrites

Yehia

Ismail

Mohamed

2015

J Supercond Nov Magn

View full text Add to dashboard Cite

show abstract

“…The improvement is largely associated with the increase of magnetocrystalline anisotropy [25] as well as coercivity and saturation magnetization [26] and the latter two parameters can be either isotropic or anisotropic depending on the variation in the f electron orbital contribution to magnetic interactions [27].…”

Section: Introductionmentioning

confidence: 99%

Effect of Pr3+ substitution on the microstructure, specific surface area, magnetic properties and specific heating rate of Ni0.5Zn0.5Pr Fe2−O4 nanoparticles synthesized via sol–gel method

Yan

Gao

et al. 2015

Journal of Alloys and Compounds

View full text Add to dashboard Cite

xia. (2015) Effect of Pr3+ substitution on the microstructure, specific surface area, magnetic properties and specific heating rate of Ni0.5Zn0.5PrxFe2−xO4 nanoparticles synthesized via sol-gel method. Journal of Alloys and Compounds,. Permanent WRAP URL:http://wrap.warwick.ac.uk/94091 Copyright and reuse:The Warwick Research Archive Portal (WRAP) makes this work by researchers of the University of Warwick available open access under the following conditions. Copyright © and all moral rights to the version of the paper presented here belong to the individual author(s) and/or other copyright owners. To the extent reasonable and practicable the material made available in WRAP has been checked for eligibility before being made available.Copies of full items can be used for personal research or study, educational, or not-for-profit purposes without prior permission or charge. Provided that the authors, title and full bibliographic details are credited, a hyperlink and/or URL is given for the original metadata page and the content is not changed in any way. A note on versions:The version presented here may differ from the published version or, version of record, if you wish to cite this item you are advised to consult the publisher's version. Please see the 'permanent WRAP url' above for details on accessing the published version and note that access may require a subscription. Abstract: A series of Ni-Zn ferrite nanoparticles with a nominal composition of Ni0.5Zn0.5Prx Fe2-xO4 (x=0.000 -0.100 with steps of 0.025) has been synthesized by a sol-gel method. The effect of composition and calcination temperature on the morphology, specific surface area, magnetic properties and specific heating rate has been studied. The Ni-Zn-Pr ferrites have a single spinel (NZF) phase at Pr loadings below 5 at%. A minor amount of an orthorhombic PrFeO3 phase is present in the Ni-Zn-Pr ferrites at Pr loadings above 5 at%. At a Pr loading of 10 at%, the specific surface area increases six-fold as compared to that of the non-doped Ni0.5Zn0.5Fe2O4 sample. As the Pr loading increases, the saturation magnetization, remnant magnetization and coercivity increase and reach the maximum at x = 0.05 and then decrease. The maximum values of these parameters are 67.0 emu/g, 9.7 emu/g and 87.2Oe, respectively. Under radiofrequency field (frequency: 295 kHz, intensity: 500 Oe), the highest heating rate of 1.65 K/s was observed over the sample with x = 0.025 which is 2.5 times higher than that of Ni0.5Zn0.5Fe2O4.

show abstract

“…The FTIR spectrum reveals also the presence of other absorption bands at 1663 and 3472cm -1 . These bands can be ascribed to the tensional stretching modes and H-O-H bending vibration of the free or absorbed water molecules (31,32) . It seems that increasing the Fe/Co content enhances the formation of such organic components.…”

Section: Fourier Transform-infra Red Spectroscopymentioning

confidence: 99%

Phase Formation and Crystallinity-Dependent Magnetic Parameters of Co1-xFe2+xO4 Nanoparticals

Eyssa¹

2015

AJPA

View full text Add to dashboard Cite

Nano crystalline cobalt ferrite CoFe 2 O 4 powders were synthesized using the coprecipitation method. The effect of the calcination temperature and the Fe 3+ /Co 2+ molar ratio on the phase formation, macro and microstructure and magnetic properties was studied systematically. The Fe 3+ /Co 2+ was controlled to equal 2 and 2.75 while the annealing temperature (T a ) was adjusted to vary from 600 to 1000C o . the obtained powders were investigated using x-ray diffraction (XRD) analysis, Field emission scanning electron microscope (FESEM), Fourir transformation infrared spectroscopy (FTIR) and vibrating sample magnetometer (VSM). For both the Fe 3+ /Co 2+ ratios, the XRD results indicat the formation of well crystallized cubic spinel cobalt ferrite phase for the precursors annealed at 600C o up to 1000C o . However a second rhombohedral hematite phase whose content varies respectively from 3% and 15% was formed as the Fe 3+ /Co 2+ varied from 2 to 2.75 at T a =800 and 1000C o . The crystallite size (D β ) as determined applying the win-fit program was found also to decrease from 54.5 to 48.6nm accompanied by an increase of the root mean square strain < e g >. Using Rditveld analysis no effect on the value of the lattice parameter (a) was detected. The FESEM micrographs reveal the formation of highly agglomerated particles for Fe 3+ /Co 2+ =2.75 and T a =1000C o . The FTIR analysis confirm the formation of the spinel structure phase for both Fe 3+ /Co 2+ ratios at 1000C o , however the absorption bands shift to higher frequencies for Fe 3+ /Co 2+ =2.75. Other bands at 1663 and 3472cm -1 ascribed to free or absorbed water molecules were also detected for this ratio. The Fe 3+ /Co 2+ molar ratio was found to have a significant effect on the magnetic properties of the produced cobalt ferrite. The calculated magnetic parameters: the saturation magnetization (M S = 71.219emu/g), the coricivity (H C = 1443.8Oe) and the remanence ratio (M r /M S = 0.405) were recorded to decrease as the Fe 3+ /Co 2+ increases except for the curie temperature (T C ) which increase from 405 to 410C o .

show abstract

Magnetic and structural properties of nano sized Dy-doped cobalt ferrite synthesized by co-precipitation

Cited by 212 publications

References 38 publications

Synthesis and Characterization of Ultrasmall Nanocrystalline Zn-substituted Ni-Sm-Ga Ferrites

Synthesis and Characterization of Ultrasmall Nanocrystalline Zn-substituted Ni-Sm-Ga Ferrites

Effect of Pr3+ substitution on the microstructure, specific surface area, magnetic properties and specific heating rate of Ni0.5Zn0.5Pr Fe2−O4 nanoparticles synthesized via sol–gel method

Phase Formation and Crystallinity-Dependent Magnetic Parameters of Co1-xFe2+xO4 Nanoparticals

Contact Info

Product

Resources

About