Facile Fabrication and Magnetic Characterization of Ferrite CoFe₂O₄ Nanotube Arrays

Annealing conditions involved in the formation of nanomaterials can affect their morphologies, structures, and thereby affect their properties. Here, by adjusting the annealing temperature and time, large‐scale ferrite CoFe 2 O 4 hollow nanotube arrays have been successfully fabricated by annealing of CoFe alloy nanowires in air. Samples before and after annealing are characterized in detail by using the X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, and physical properties measurement system at room temperature, respectively. This process provides a simple route to synthesize large‐scale one‐dimensional (1‐D) hollow CoFe 2 O 4 nanotubes, and explores a way for the development of metal oxides with specific architecture. However, the morphology change is not completely in agreement with the classical structural change theory. The magnetic characterization indicates that the morphology changes influence the magnetism, based on this finding, it is inferred that it is due to changes in magnetic interactions in the sample.