BaFe12O19 Single-Particle-Chain Nanofibers: Preparation, Characterization, Formation Principle, and Magnetization Reversal Mechanism

详细信息    查看全文

• 作者：Junli Zhang ; Jiecai Fu ; Fashen Li ; Erqing Xie ; Desheng Xue ; Nigel J. Mellors ; Yong Peng
• 刊名：ACS Nano
• 出版年：2012
• 出版时间：March 27, 2012
• 年：2012
• 卷：6
• 期：3
• 页码：2273-2280
• 全文大小：1011K
• 年卷期：v.6,no.3(March 27, 2012)
• ISSN：1936-086X

文摘

BaFe₁₂O₁₉ single-particle-chain nanofibers have been successfully prepared by an electrospinning method and calcination process, and their morphology, chemistry, and crystal structure have been characterized at the nanoscale. It is found that individual BaFe₁₂O₁₉ nanofibers consist of single nanoparticles which are found to stack along the nanofiber axis. The chemical analysis shows that the atomic ratio of Ba/Fe is 1:12, suggesting a BaFe₁₂O₁₉ composition. The crystal structure of the BaFe₁₂O₁₉ single-particle-chain nanofibers is proved to be M-type hexagonal. The single crystallites on each BaFe₁₂O₁₉ single-particle-chain nanofibers have random orientations. A formation mechanism is proposed based on thermogravimetry/differential thermal analysis (TG-DTA), X-ray diffraction (XRD), and transmission electron microscopy (TEM) at six temperatures, 250, 400, 500, 600, 650, and 800 掳C. The magnetic measurement of the BaFe₁₂O₁₉ single-particle-chain nanofibers reveals that the coercivity reaches a maximum of 5943 Oe and the saturated magnetization is 71.5 emu/g at room temperature. Theoretical analysis at the micromagnetism level is adapted to describe the magnetic behavior of the BaFe₁₂O₁₉ single-particle-chain nanofibers.

Keywords:

BaFe₁₂O₁₉; electrospinning; single-particle-chain nanofibers; formation principle; CBED; EDX elemental mapping; high saturation magnetization; magnetic reversal mechanism