Preparation of elongated iron oxide nanostructures assembled in alumina membranes

In the present work, a new way of manufacturing transition metal oxide nanowires is reported. Specifically, magnetite nanowires were prepared using a combination of electrodeposition with subsequent heat treatment in different atmospheres. After depositing the iron wires, the oxidation process was carried out using a normal laboratory atmosphere and, in another situation, treatment was carried out with an argon atmosphere. In both cases magnetite nanowires with a diameter of 250nm were obtained. Wire obtained in both cases a percentage of hematite that may have been generated in an intermediate phase of the process. X-ray diffraction and Raman spectroscopy measurements corroborate these results. In addition, a study was carried out with magnetic measurements measuring magnetization as a function of the field for a field parallel and perpendicular to the wires. The results show that the combination of these two preparation steps is an excellent alternative to obtain elongated transition metal oxide structures. The magnetic measurements, being sensitive to all structural changes, show that for the sample obtained with argon flux there is a more open magnetization curve that corresponds to the microscopy images in which the samples obtained without flux are less defined in shape.