Synthesis, characterization and magnetic properties of Fe–Al nanopins

✍ Scribed by W.S. Zhang; E. Brück; W.F. Li; P.Z. Si; D.Y. Geng; Z.D. Zhang

• Publisher: Elsevier Science
• Year: 2005
• Tongue: English
• Weight: 308 KB
• Volume: 370
• Category: Article
• ISSN: 0921-4526
• DOI: 10.1016/j.physb.2005.09.001

✦ Synopsis

We report the synthesis of Fe-Al nanopins using arc discharge. The morphology and chemical composition of the Fe-Al nanopins were studied by means of X-ray diffraction, X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDX), and high-resolution transmission electron microscopy (HRTEM). The nanopins are composed of a spherical base of about 20-100 nm and a needle-like tip of about several hundred nanometers. EDX and HRTEM studies indicate that the spherical base is mainly composed of a-Fe and FeAl core coated with a thin Al 2 O 3 layer, while the needle-like part contains only Al and O and corresponds to Al 2 O 3 . The formation mechanism of the nanopins is suggestive of a vapor-liquid-solid (VLS) growth process. The as-prepared Fe-Al nanopins show ferromagnetic properties. The temperature dependence of the magnetization at high temperatures indicates the existence of some phase transformations.