Variation of polymer-template pore geometry as a means of controlling the magnetic properties of metallic nanostructures

Resumo

The influence of pore geometry of polyethylene terephthalate track-etched membranes on the structural, conducting, and magnetic characteristics of cobalt nanotubes (NTs) synthesized by electrochemical deposition has been studied. It has been found that there are significant differences in average size of crystallites and texture coefficients between various forms of cobalt nanotubes. Thus, the α-Co hexagonal closepacked phase dominates in Co-NT samples with cylindrical and hourglass pore shapes and the β-Co facecentered cubic phase prevails in conical Co nanotubes. Measurements of the magnetic properties have shown that the coercivity of cylindrical Co nanotubes is almost two times that of the conical forms because of crystal anisotropy of nanotube-forming cobalt crystallites.