Co-B nanotubes were prepared via an electroless deposition method. The
morphology, magnetic properties and the magnetization reversal mechanism of the
nanotubes were investigated. Deposition was carried out in porous polycarbonate
membranes leading to the formation of Co-B nanotubes with an average external
diameter of 400 nm and lengths up to 6 μm. Electroless deposition resulted in
the formation of alloys with composition Co70B30 and a specific magnetization of
65.6 J T−1kg−1, which is about 40 % of that of pure Co (161 J T−1kg−1). The
transversal and vortex modes were identified as the mechanisms responsible for
magnetization reversal in the nanotubes. A crossover between the two modes is
observed at low angles and the results are in line with current models for switching
mechanisms of nanotubes.