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A novel method to fabricate CoFe2O4/SrFe12O19 composite ferrite nanofibers with enhanced exchange coupling effect.

Pan L, Cao D, Jing P, Wang J, Liu Q - Nanoscale Res Lett (2015)

Bottom Line: Nanocomposite of CoFe2O4/SrFe12O19 has been synthesized by the electrospinning and calcination process.The crystal structures, morphologies, and magnetic properties of these samples have been characterized in detail.Significantly, the hysteresis loops for the nanocomposites show a single-phase magnetization behavior, and it has been found that the exchange coupling interaction strongly exists in the CoFe2O4/SrFe12O19 magnetic nanocomposite nanofibers.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory for Magnetic and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou, 730000 People's Republic of China.

ABSTRACT
Nanocomposite of CoFe2O4/SrFe12O19 has been synthesized by the electrospinning and calcination process. A novel method that cobalt powder was used to replace traditional cobalt salt in the precursor sol-gel for electrospinning was proposed. The crystal structures, morphologies, and magnetic properties of these samples have been characterized in detail. Moreover, when the average crystallite size of the hard/soft phases reached up to an optimal value, the CoFe2O4 have an enhanced saturation magnetization of 62.8 emu/g and a coercivity of 2,290 Oe. Significantly, the hysteresis loops for the nanocomposites show a single-phase magnetization behavior, and it has been found that the exchange coupling interaction strongly exists in the CoFe2O4/SrFe12O19 magnetic nanocomposite nanofibers.

No MeSH data available.


Related in: MedlinePlus

TEM and HRTEM images and EDX spectrum of CoFe2O4/SrFe12O19nanofibers. TEM images (a, b), HRTEM image (c), and EDX spectrum (d) of CoFe2O4/SrFe12O19 nanofibers with a Co/Sr2+ molar ratio of 1.8. TEM image (e), top left inset in (e) showing a HRTEM pattern, and EDX spectrum (f) of CoFe2O4/SrFe12O19 nanofibers with a Co/Sr2+ molar ratio of 8.0.
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Fig4: TEM and HRTEM images and EDX spectrum of CoFe2O4/SrFe12O19nanofibers. TEM images (a, b), HRTEM image (c), and EDX spectrum (d) of CoFe2O4/SrFe12O19 nanofibers with a Co/Sr2+ molar ratio of 1.8. TEM image (e), top left inset in (e) showing a HRTEM pattern, and EDX spectrum (f) of CoFe2O4/SrFe12O19 nanofibers with a Co/Sr2+ molar ratio of 8.0.

Mentions: The representative TEM images of the CoFe2O4/SrFe12O19 nanofibers with the Co/Sr2+ molar ratio of 1.8 are presented in Figure 4a,b; they show a continuously linear structure and uniform diameter, which is corresponding to the above SEM observation (Figure 2). It is easily seen that the nanofibers consisted of two sizes of grains: one looks like hexagonal plate type structure SrFe12O19 and another is cubical CoFe2O4. Contrasting to the result of the average crystallite size calculated by XRD, the crystallite size is smaller than the grain obtained by TEM, so we do not make sure that every grain is single crystalline. Compared with the sample in Figure 4b, the CoFe2O4/SrFe12O19 nanofibers with a Co/Sr2+ molar ratio of 8.0 in Figure 4e present a smoother surface, and the grains are smaller than the other samples. As shown in Figure 4e, the nanofibers are composed of uniform grains, and the grains densely stacked along the direction of nanofiber axis.Figure 4


A novel method to fabricate CoFe2O4/SrFe12O19 composite ferrite nanofibers with enhanced exchange coupling effect.

Pan L, Cao D, Jing P, Wang J, Liu Q - Nanoscale Res Lett (2015)

TEM and HRTEM images and EDX spectrum of CoFe2O4/SrFe12O19nanofibers. TEM images (a, b), HRTEM image (c), and EDX spectrum (d) of CoFe2O4/SrFe12O19 nanofibers with a Co/Sr2+ molar ratio of 1.8. TEM image (e), top left inset in (e) showing a HRTEM pattern, and EDX spectrum (f) of CoFe2O4/SrFe12O19 nanofibers with a Co/Sr2+ molar ratio of 8.0.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4385261&req=5

Fig4: TEM and HRTEM images and EDX spectrum of CoFe2O4/SrFe12O19nanofibers. TEM images (a, b), HRTEM image (c), and EDX spectrum (d) of CoFe2O4/SrFe12O19 nanofibers with a Co/Sr2+ molar ratio of 1.8. TEM image (e), top left inset in (e) showing a HRTEM pattern, and EDX spectrum (f) of CoFe2O4/SrFe12O19 nanofibers with a Co/Sr2+ molar ratio of 8.0.
Mentions: The representative TEM images of the CoFe2O4/SrFe12O19 nanofibers with the Co/Sr2+ molar ratio of 1.8 are presented in Figure 4a,b; they show a continuously linear structure and uniform diameter, which is corresponding to the above SEM observation (Figure 2). It is easily seen that the nanofibers consisted of two sizes of grains: one looks like hexagonal plate type structure SrFe12O19 and another is cubical CoFe2O4. Contrasting to the result of the average crystallite size calculated by XRD, the crystallite size is smaller than the grain obtained by TEM, so we do not make sure that every grain is single crystalline. Compared with the sample in Figure 4b, the CoFe2O4/SrFe12O19 nanofibers with a Co/Sr2+ molar ratio of 8.0 in Figure 4e present a smoother surface, and the grains are smaller than the other samples. As shown in Figure 4e, the nanofibers are composed of uniform grains, and the grains densely stacked along the direction of nanofiber axis.Figure 4

Bottom Line: Nanocomposite of CoFe2O4/SrFe12O19 has been synthesized by the electrospinning and calcination process.The crystal structures, morphologies, and magnetic properties of these samples have been characterized in detail.Significantly, the hysteresis loops for the nanocomposites show a single-phase magnetization behavior, and it has been found that the exchange coupling interaction strongly exists in the CoFe2O4/SrFe12O19 magnetic nanocomposite nanofibers.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory for Magnetic and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou, 730000 People's Republic of China.

ABSTRACT
Nanocomposite of CoFe2O4/SrFe12O19 has been synthesized by the electrospinning and calcination process. A novel method that cobalt powder was used to replace traditional cobalt salt in the precursor sol-gel for electrospinning was proposed. The crystal structures, morphologies, and magnetic properties of these samples have been characterized in detail. Moreover, when the average crystallite size of the hard/soft phases reached up to an optimal value, the CoFe2O4 have an enhanced saturation magnetization of 62.8 emu/g and a coercivity of 2,290 Oe. Significantly, the hysteresis loops for the nanocomposites show a single-phase magnetization behavior, and it has been found that the exchange coupling interaction strongly exists in the CoFe2O4/SrFe12O19 magnetic nanocomposite nanofibers.

No MeSH data available.


Related in: MedlinePlus