Oxygen-vacancy-induced local ferromagnetism as a driving mechanism in enhancing the magnetic response of ferrites

Torres, C.E. Rodrı́guez; Pasquevich, G. A.; Zélis, P. Mendoza; Golmar, F.; Heluani, S. P.; Nayak, Sanjeev K.; Adeagbo, Waheed A.; Hergert, W.; Hoffmann, Martin; Ernst, A.; Esquinazi, P.; Stewart, S. J.

doi:10.1103/physrevb.89.104411

Cited by 89 publications

(38 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…So, in this case decreased bond angle weakens the AFM super-exchange interaction and in effect causes the spin canting away from the perfect AFM structure and thus induce ferromagnetism. Besides this, uncompensated spins originated from Fe 3+ due to oxygen vacancy, improve magnetism [30]. However, improved ferromagnetism is observed up to 10% Mo doping and in fact highest Ms is observed for BBFMO-10.…”

Section: Magnetic Propertymentioning

confidence: 95%

Influence of Ba and Mo co-doping on the structural, electrical, magnetic and optical properties of BiFeO₃ ceramics

Sen

Hasan

Islam

et al. 2020

Mater. Res. Express

View full text Add to dashboard Cite

In this work, -Bi Ba Fe Mo O x x 0.8 0.2 13 (x = 0, 0.5, 0.10 and 0.15) ceramics were synthesized by conventional solid-state reaction to evaluate the influence of Ba 2+ and Mo 6+ co-doping on the structure, morphology, electrical, magnetic and optical properties of BiFeO 3 ceramic. Rietveld refinement of x-ray diffraction data was done to obtain the subtle structural information. A tetragonal structure of P4mm type was revealed for Bi Ba FeO 0.8 0.2 3 (x = 0) ceramic. Evolution of rhombohedral (R3c) phase was observed with Mo 6+ doping and a complete transformation to R3c phase from P4mm was found for 15 wt% Mo 6+ doping. This type of transformation causes distortion in the structure and results in changing bond angle. Magnetization was found to be improved with increasing the percentage of Mo 6+ up to 10 wt%. Canting of spin due to the change in Fe-O-Fe bond angle is believed to be the main reason behind this improvement. One secondary phase BaMoO 4 was found and becomes prominent with Mo 6+ doping. Possible formation of this impurity and its correlation with properties are explained. Microstructural analysis was done to observe the Ba 2+ and Mo 6+ co-doping effect on grain size and distribution. A correlation of grain size with electric and magnetic properties is drawn and elucidated. Dielectric constant shows an increasing trend with Mo 6+ doping. Reduction in oxygen vacancy, due to charge compensation upon high charged Mo 6+ addition, believed to be the staple reason behind the dielectric constant increment. Lastly, optical band gap energy found to be decreased with the addition of Mo 6+ and possible reasons behind this are evaluated. Overall, codoping of Ba 2+ and Mo 6+ found to have a positive influence over materials electrical, optical as well as magnetic property.

show abstract

Section: Magnetic Propertymentioning

confidence: 95%

Influence of Ba and Mo co-doping on the structural, electrical, magnetic and optical properties of BiFeO₃ ceramics

Sen

Hasan

Islam

et al. 2020

Mater. Res. Express

View full text Add to dashboard Cite

show abstract

“…Magnetic spinels are a remarkable class of materials, not only for their many applications, but also because of a wealth of new physics that continues to emerge from their fundamental investigations [1][2][3][4][5][6]. These properties result from many variations of the magnetic and nonmagnetic ions that can be accommodated on the tetrahedral A sites and the octahedral B sites in the AB 2 O 4 spinel structure, thus affecting the magnitudes of the superexchange interactions J AA , J BB , and J AB [7][8][9].…”

Section: Introductionmentioning

confidence: 99%

Magnetic compensation, field-dependent magnetization reversal, and complex magnetic ordering inCo2TiO4

et al. 2015

View full text Add to dashboard Cite

The complex nature of magnetic ordering in the spinel Co 2 TiO 4 is investigated by analyzing the temperature and magnetic field dependence of its magnetization (M), specific heat (C p ), and ac magnetic susceptibilities χ and χ . X-ray diffraction of the sample synthesized by the solid-state reaction route confirmed the spinel structure whereas x-ray photoelectron spectroscopy shows its electronic structure to be

show abstract

“…Additionally, it has been reported that oxygen vacancies in ferrite samples leads to modification of magnetization and transport properties arising as a result change in the valence state of Fe ions and redistribution of electrons. 30,31 In our case the Oxygen vacancies do not change valence state of Fe which can modify the magnetization. Therefore, the role of Oxygen vacancies in the magnetism of these compounds with the probes we have investigated is not very significant.…”

Section: Magnetic Propertiesmentioning

confidence: 58%

Crystal structure and magnetic properties of Bi0.8A0.2FeO3 (A = La, Ca, Sr, Ba) multiferroics using neutron diffraction and Mossbauer spectroscopy

et al. 2014

View full text Add to dashboard Cite

Bi0.8A0.2FeO3 (A = La, Ca, Sr, Ba) multiferroics were studied using x-ray, neutron diffraction and magnetization techniques. All the samples crystallized in rhombohedral structure with space group R3c. The compounds exhibit antiferromagnetic (AFM) ordering at 300 K and no evidence of further structural or magnetic transition was observed on lowering of temperature below it. The magnetic structure of these substituted compounds are found to be collinear G-type AFM structure as against the non collinear incommensurate magnetic structure reported in the case of parent compound. The moments on Fe at 6 K are aligned along the a-axis in the case of Ca-doped sample. With increase in the ionic radii of dopant, the moments are found to be aligned in the ac plane and the angle of tilt away from the a-axis increases. The observed change in the magnetic structure with substitution is attributed to the intrinsic structural distortion as evidenced by the change in the bond angle (Fe-O-Fe) and bond distances (Bi-O, Fe-O). It has been found that heterovalent substitution A2+ results in the formation of oxygen vacancies in the parent lattices as the possibility of Fe4+ ruled out by Mössbauer spectra recorded at room temperature. Higher value of remnant magnetization (0.4187 emu/g) and coercivity (4.7554kOe) is observed in Bi0.8Ba0.2FeO3 sample in comparison to other substituted samples revealing a strong correlation between ionic radii and magnetization.

show abstract

Oxygen-vacancy-induced local ferromagnetism as a driving mechanism in enhancing the magnetic response of ferrites

Cited by 89 publications

References 38 publications

Influence of Ba and Mo co-doping on the structural, electrical, magnetic and optical properties of BiFeO₃ ceramics

Influence of Ba and Mo co-doping on the structural, electrical, magnetic and optical properties of BiFeO₃ ceramics

Magnetic compensation, field-dependent magnetization reversal, and complex magnetic ordering inCo2TiO4

Crystal structure and magnetic properties of Bi0.8A0.2FeO3 (A = La, Ca, Sr, Ba) multiferroics using neutron diffraction and Mossbauer spectroscopy

Contact Info

Product

Resources

About

Oxygen-vacancy-induced local ferromagnetism as a driving mechanism in enhancing the magnetic response of ferrites

Cited by 89 publications

References 38 publications

Influence of Ba and Mo co-doping on the structural, electrical, magnetic and optical properties of BiFeO3 ceramics

Influence of Ba and Mo co-doping on the structural, electrical, magnetic and optical properties of BiFeO3 ceramics

Magnetic compensation, field-dependent magnetization reversal, and complex magnetic ordering inCo2TiO4

Crystal structure and magnetic properties of Bi0.8A0.2FeO3 (A = La, Ca, Sr, Ba) multiferroics using neutron diffraction and Mossbauer spectroscopy

Contact Info

Product

Resources

About

Influence of Ba and Mo co-doping on the structural, electrical, magnetic and optical properties of BiFeO₃ ceramics

Influence of Ba and Mo co-doping on the structural, electrical, magnetic and optical properties of BiFeO₃ ceramics