Magnetic nanotubes produced by hydrogen reduction

Abstract

FePt and Fe 3 O 4 nanotubes are produced by hydrogen reduction in nanochannels of porous alumina templates and investigated by electron microscopy, x-ray diffraction, and superconducting quantum interference device magnetometry. Loading the templates with an Fe chloride and Pt chloride mixture, followed by hydrogen reduction at 560°C, leads to the formation of ferromagnetic FePt nanotubes in the alumina pores. An Fe nitrate solution, thermally decomposed at 250°C and reduced in hydrogen for 2.5 h at the same temperature, yields Fe 3 O 4 tubes. The versatility of the method indicates that materials with a wide range of parameters can be produced.

Spin wave spectrum of magnetic nanotubes

“…From the experimental standpoint there are some methods for the fabrication of MNs, as hydrogen reduction [3], electrodeposition [4] and atomic layer deposition [5] into porous membranes. There are also some fundamental works involved to the knowledge of basic magnetic properties, as the internal magnetic structure [6][7][8][9][10], nucleation phenomena [10][11][12][13], reversal process [14,15], domain wall (DW) motion [16] and spin waves [6,17,18].…”

Template‐based Synthesis and Magnetic Properties of Cobalt Nanotube Arrays

“…Various nanotubes have been synthesized in template matrices, and they have made important contributions to fundamental research in the areas of catalysis, [2,3] sensors, [4,5] electronic or magnetic devices, [6][7][8][9][10][11] and biological separation and transport. [12] Among the synthesis methods, electroless deposition has been proven to be efficient in synthesizing nanotubes, such as polyaniline, [10] FePt and Fe 3 O 4 nanotubes, [7,13] Co, [14,15] and Ni [16] nanotubes. Metallic nanotubes have also been fabricated by electrodeposition in chemically modified anodic aluminum oxide (AAO) channels.…”

Magnetic properties of TiO2/Ni hybrid nanotube arrays by electrophoretic deposition

“…Their potential applications in nonvolatile magnetic memory devices or high-resolution magnetic field sensors have been widely studied [1,2]. Moreover, magnetic metals with one-dimensional nanostructures as well as obvious magneto-anisotropy are good candidates for high-density magnetic recording media [3]. Various techniques are employed for the fabrication of magnetic NTs/NWs like hydrothermal method, electro-spinning or chemical techniques, etc.…”

“…Various techniques are employed for the fabrication of magnetic NTs/NWs like hydrothermal method, electro-spinning or chemical techniques, etc. [3][4][5][6]. A more straightforward approach is the template technique in which the NTs/NWs are grown into pores of a template generally of a porous alumina.…”