Mössbauer study of cobalt ferrite nanocrystals substituted with rare-earth Y3+ ions

Meng, Xiuxia; Li, Haibo; Chen, Jingyan; Liu, Mei; Wang, Keqiang; Li, Xiao

doi:10.1016/j.jmmm.2008.10.041

Cited by 110 publications

(34 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We have observed that the lattice constant decreases with the Ho 3þ concentration up to x ¼ 0.05. Similar decrease in lattice parameters have been observed for RE 3þ ions substituted cobalt ferrite nanocrystals [39,40]. The observed decrease of lattice constant could be explained on the basis of rearrangement of cations between the A-site and B-site in order to relax the lattice strain (discussed in the above section).…”

Section: Results and Discussion 31 Structural Analysissupporting

confidence: 76%

Effect of Ho³⁺substitution on the cation distribution, crystal structure and magnetocrystalline anisotropy of nanocrystalline cobalt ferrite

Kumar

Kar

2012

Journal of Experimental Nanoscience

View full text Add to dashboard Cite

Ho 3þ ion-substituted nanocrystalline cobalt ferrite materials with the chemical formula CoFe 2Àx Ho x O 4 for x ¼ 0.0, 0.025, 0.05, 0.075 and 0.1 have been synthesised by standard citrate precursor method. Crystal structure and phase purity have been studied by powder X-ray diffraction (XRD) method by employing Rietveld refinement technique. The distribution of cations between the tetrahedral site (A-site) and octahedral site (B-site) has been estimated by Rietveld analysis. The refinement result shows that Ho 3þ ion has a strong preference for octahedral sites (B-sites). The lattice constants decrease with the Ho 3þ concentration up to x ¼ 0.05. Crystallite size decreases with the Ho 3þ concentration. The magnetic hysteresis loop measurements have been carried out at room temperature using a vibrating sample magnetometer (VSM) over a field range of AE2 T. The magnetisations in saturation have been analysed by employing the 'law of approach (LA)' technique. The magnetocrystalline anisotropy constant and saturation magnetisation are found to decrease with the Ho 3þ concentration up to x ¼ 0.05. The coercivity decreases with the Ho 3þ concentration. The vibrational modes of the octahedral and tetrahedral metal complex in the sample have been carried out using Fourier transform infrared spectroscopy (FT-IR). The FT-IR spectra of the samples have been analysed in the wave number range of 350-1000 cm À1 . We have observed two prominent absorption bands which are assigned to tetrahedral and octahedral metal complexes. The elemental analysis has been carried out using energy dispersive spectroscopy (EDS) with the help of field emission scanning electron microscope (FE-SEM) and the results reveal that, elements are as per the stoichiometric ratio in all the samples.

show abstract

Section: Results and Discussion 31 Structural Analysissupporting

confidence: 76%

Effect of Ho³⁺substitution on the cation distribution, crystal structure and magnetocrystalline anisotropy of nanocrystalline cobalt ferrite

Kumar

Kar

2012

Journal of Experimental Nanoscience

View full text Add to dashboard Cite

show abstract

“…Presence of Dy 3+ ions results in the weak super-exchange interactions in ferrites [77]. Slight increase of magnetic strength is observed for CoFe2-xYxO4 (x=0, 0.1, 0.3, 0.5) and Zn0.5Ni0.5R0.02Fe1.98O4 (R=Y, Gd and Eu) with respect to their undoped counterparts [78,79]. Other factors which may be considered are spin-orbit coupling and 3d-4f coupling.…”

Section: Change Of Exchange Interactionmentioning

confidence: 99%

Solubility limit, magnetic interaction and conduction mechanism in rare earth doped spinel ferrite

Singh¹,

Kumar²,

Srivastava³

et al. 2016

Appl. Sci. Lett.

View full text Add to dashboard Cite

In present review we have focused various issues like solubility limit, magnetic interaction and conduction mechanism of rare earth doped ferrite. Cumulative effects of valence state, magnetic moments of rare earth ions, weakening/strengthening of exchange interaction and magnetic ordering in rare earth ion doped ferrite are responsible for magnetic behavior. It is proposed that characterization techniques based on synchrotron radiation like X-ray absorption spectroscopy and X-ray magnetic circular dichroism can open pathways to prove these assumptions.Keywords: Rare earth, ferrites, magnetic interaction, valence state 1.INTRODUCTIONSpinel ferrites are ferrimagnetic material which have numerous technological applications [1][2][3]. Moreover, nanoparticles of these ferrites are being utilized in high-density magnetic information storage, magnetic resonance imaging, drug delivery etc. [4][5][6]. These several applications are based on magnetic and electrical behavior of ferrites [1][2][3][4][5][6]. These properties depend on various factors like, ionic radii, nature of hybridization, presence of doped atom in host lattice apart from the particle size [7][8][9][10]. Thus, research is being carried out for doped ferrite systems in order to understand the altered behavior and to optimize them for different applications [11][12][13][14][15]. In recent years, rare earth (RE) doped ferrites become interesting due to their superiority for various applications over other doped ferrite systems [17][18][19][20][21][22]. These systems become radioactive and exhibit potentential for biomedical applications [19] along-with efficient tumor passive targeting [23]. Improved capability of dye removal [24], waste water treatment [25], degradation of organic pollutants through photocatalytic activity [26] are other important fields of utilization of these ferrites. These ferrites exhibit enhanced magneto optical kerr (MOKE) effect [20] and excellent microwave absorption properties [21,22]. Thus, these ferrites cover a wide range of applications chiefly based on their magnetic characteristics [17][18][19][20][21][22][23][24][25]. However, there is lack of understanding of magnetic interaction, conduction mechanism inside these ferrites [15,16]. Thus purpose of this review article is to discuss these issues and to give prospects for future research in this direction. SPINEL FERRITEThe general formula for spinel ferrite is MO:Fe2O3 where, M is a divalent transition metal ion. Spinel name is given due to resemblance of structure of these ferrites with mineral spinel MgO.Al2O3. In this structure, oxygen ions are packed quite close together in face centred cubic arrangement and metal ions occupy spaces between them (Fig. 1). These spaces are categorized as tetrahedral (A) and octahedral (B) sites when surrounded by four and six oxygen ions respectively (Fig. 1).In a unit cell of spinel ferrite, there exists 64 and 32 A and B-sites respectively. Only 1/8 th and 1/2 th of A and B-sites are occupied [27]. Metal ions are distributed among A a...

show abstract

“…Nanomaterials are rapidly expanding and used in various areas of research, such as food, feed, health management and environmental aspects (Bouwmeester et al 2007;Kiruba Daniel et al 2013). Metal-oxide nanoparticles draw attention due to their unique magnetic properties and other characteristics such as excellent chemical stability and mechanical hardness (Meng et al, 2009;Phua et al, 2009;Sanpo et al, 2013). Cobalt ferrite (CoFe 2 O 4 ) nanoparticles offer potential applications in several fields such as food, medicine, cancer treatment (Jamon et al, 2009) and other applications (Amiri and Shokrollahi, 2013;Sanpo et al, 2013a).…”

Section: Introductionmentioning

confidence: 99%

Synthesis and characterization of cobalt ferrites nanoparticles with cytotoxic and antimicrobial properties

Hathout¹,

Aljawish²,

Sabry³

et al. 2017

J App Pharm Sci

View full text Add to dashboard Cite

Recently, the application of nanotechnology in food sector and the agriculture attract the attention compared to its biomedical application. The aims of the current study was to synthesize and characterize cobalt ferrites nanoparticles [(CoFe2O4) NPs] by combustion method employing glycine as fuels and to evaluate their antimicrobial against pathogenic bacteria and fungi and anti cancer properties against MCF-7 breast cancer cells line. The results indicated that the particles size of the synthesized (CoFe2O4) NPs was 40 nm. These (CoFe2O4) NPs showed potential antibacterial properties against Gram-negative bacteria (Escherichia coli, Salmonella typhi) and Gram-positive bacteria (Staphylococcus aureus, Bacillus cereus) as well as the pathogenic fungi (Aspergillus flavus and Aspergillus ochraceus) in a dose dependent manner with maximum concentration of 1.8 mg/ml. (CoFe2O4) NPs also showed weak antiradical but have cytotoxic effects against MCF-7 breast cancer cells line and succeeded to decrease the cell viability at a concentration of 2 mg/ml. It could be concluded that (CoFe2O4) NPs is a promise candidate as antimicrobial and anticancer agent for food sector and medical application.

show abstract

Mössbauer study of cobalt ferrite nanocrystals substituted with rare-earth Y3+ ions

Cited by 110 publications

References 15 publications

Effect of Ho³⁺substitution on the cation distribution, crystal structure and magnetocrystalline anisotropy of nanocrystalline cobalt ferrite

Effect of Ho³⁺substitution on the cation distribution, crystal structure and magnetocrystalline anisotropy of nanocrystalline cobalt ferrite

Solubility limit, magnetic interaction and conduction mechanism in rare earth doped spinel ferrite

Synthesis and characterization of cobalt ferrites nanoparticles with cytotoxic and antimicrobial properties

Contact Info

Product

Resources

About

Mössbauer study of cobalt ferrite nanocrystals substituted with rare-earth Y3+ ions

Cited by 110 publications

References 15 publications

Effect of Ho3+substitution on the cation distribution, crystal structure and magnetocrystalline anisotropy of nanocrystalline cobalt ferrite

Effect of Ho3+substitution on the cation distribution, crystal structure and magnetocrystalline anisotropy of nanocrystalline cobalt ferrite

Solubility limit, magnetic interaction and conduction mechanism in rare earth doped spinel ferrite

Synthesis and characterization of cobalt ferrites nanoparticles with cytotoxic and antimicrobial properties

Contact Info

Product

Resources

About

Effect of Ho³⁺substitution on the cation distribution, crystal structure and magnetocrystalline anisotropy of nanocrystalline cobalt ferrite

Effect of Ho³⁺substitution on the cation distribution, crystal structure and magnetocrystalline anisotropy of nanocrystalline cobalt ferrite