Ni Nanowires Grown in Anodic TiO2 Nanotube Arrays as Diluted Magnetic Semiconductor Nanocomposites

This chapter reports on novel synthesis of ferromagnetic/semiconductor oxide nanomaterial consisting of ferromagnetic Ni nanowires electrodeposited and grown inside the semiconductor oxide matrix of self-aligned TiO₂ nanotube arrays. Nanodimensional structures, including nanotubes, nanowires, and nanoporous architecture materials based on semiconducting metal oxides, are nowadays of fundamental interest to the development of functional nanomaterials, nanodevices, and nanosystems. It is expected that the so-formed diluted magnetic semiconductor nanocomposite made of titanium oxide nanotubes/ferromagnetic Ni nanowires will lead to new applications and device designs in the research fields of high-density magnetic data storage and spintronic devices. It has been revealed that the self-organized TiO₂ nanotubular structure appears after several hours of competition between porous oxide formation at the inner interface combined with oxide dissolution at the outer interface.