Characterization of La-Zn Substituted Co2Y Hexagonal Ferrite

Vinaykumar, R.; Kumari, Jyoti; Bera, J.

doi:10.1007/s11664-018-6486-0

Cited by 3 publications

(3 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Saturation of the initial magnetization curves is seen (Figure 3c) at a magnetic field of 50 kOe, the magnetization values being 34.5 emu/g and 30.4 emu/g at 4.2 K and 300 K, respectively. The M (50 kOe) values for 300 K are close to those reported by Wu et al [38] and lie between the values reported for non-substituted Ba 2 Mg 2 Fe 12 O 22 (23 emu/g) and Ba 2 Co 2 Fe 12 O 22 (34 emu/g) [13,23]. The hysteresis curve at 300 K is very narrow (about 70 Oe), while H c is about 35 Oe.…”

Section: Resultssupporting

confidence: 87%

“…This value is typical for hexaferrites whose magneto-crystalline anisotropy is planar. This H c value is slightly higher than that for unsubstituted Ba 2 Mg 2 Fe 12 O 22 (12.21 Oe) prepared following a similar route [26], but is lower than that observed for the Ba 2 Co 2 Fe 12 O 22 (70 Oe) synthesized by a solid-state method [23]. The M (50 kOe) value at 4.2 K is not much different than that for unsubstituted Ba 2 Mg 2 Fe 12 O 22 (33.57 emu/g) obtained under similar conditions [26].…”

Section: Resultsmentioning

confidence: 73%

“…They investigated in particular the influence of Co 2+ substitution of Mg 2+ on the magnetic properties and the magnetic phase transition at a magnetic field of 500 Oe. They found that the transition temperature from a ferromagnetic to a helical spin arrangement increases with increasing the cobalt concentration, and for x = 1.6 it is 226 K. In the case of Ba 2 Co 2 Fe 12 O 22 (fully substituted), this magnetic phase transition occurs at 225 K [22] and the M s and H c are 32 emu/g and 70 Oe, respectively [23,24]. The Co substitution also increases the Curie temperature from 553 K for Ba 2 Mg 2 Fe 12 O 22 to 613 K for Ba 2 Co 2 Fe 12 O 22 [17,18,22].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Study of the Structural and Magnetic Properties of Co-Substituted Ba2Mg2Fe12O22 Hexaferrites Synthesized by Sonochemical Co-Precipitation

et al. 2019

View full text Add to dashboard Cite

Ba2Mg0.4Co1.6Fe12O22 was prepared in powder form by sonochemical co-precipitation and examined by X-ray diffraction, Mössbauer spectroscopy and magnetization measurements. Careful XRD data analyses revealed the Y-type hexaferrite structure as an almost pure phase with a very small amount of CoFe2O4 as an impurity phase (about 1.4%). No substantial changes were observed in the unit cell parameters of Ba2Mg0.4Co1.6Fe12O22 in comparison with the unsubstituted compound. The Mössbauer parameters for Ba2Mg0.4Co1.6Fe12O22 were close to those previously found (within the limits of uncertainty) for undoped Ba2Mg2Fe12O22. Isomer shifts (0.27–0.38 mm/s) typical for high-spin Fe3+ in various environments were evaluated and no ferrous Fe2+ form was observed. However, despite the indicated lack of changes in the iron oxidation state, the cationic substitution resulted in a significant increase in the magnetization and in a modification of the thermomagnetic curves. The magnetization values at 50 kOe were 34.5 emu/g at 4.2 K and 30.5 emu/g at 300 K. The zero-field-cooled (ZFC) and field-cooled (FC) magnetization curves were measured in magnetic fields of 50 Oe, 100 Oe, 500 Oe and 1000 Oe, and revealed the presence of two magnetic phase transitions. Both transitions are shifted to higher temperatures compared to the undoped compound, while the ferrimagnetic arrangement at room temperature is transformed to a helical spin order at about 195 K, which is considered to be a prerequisite for the material to exhibit multiferroic properties.

show abstract

Section: Resultssupporting

confidence: 87%