Ni/Ni₃C core-shell nanochains and its magnetic properties: One-step synthesis at low temperature

One-dimensional Ni/Ni₃C core-shell nanoball chains with an average diameter by around 30 nm were synthesized by means of a mild chemical solution method using a soft template of trioctylphosphine oxide (TOPO). It was revealed that the uniform Ni nanochains were capped with Ni₃C thin shells by about 1-4 nm in thickness and each Ni core consists of polygrains. The coercivity of the core-shell nanochains is much enhanced (600 Oe at 5 K) and comparable with single Ni nanowires due to the one-dimensional shape anisotropy. Deriving from the distinctive structure of Ni core and Ni₃C shell, this architecture may possess a possible bifunctionality. This unique architecture is also useful for the study on the magnetization reversal mechanism of one-dimensional magnetic nanostructure.