Low-temperature CVD synthesis of carbon-encapsulated magnetic Ni nanoparticles with a narrow distribution of diameters

摘要

Carbon-encapsulated magnetic nanoparticles (CEMNPs) have received considerable attention in recent years due to their expectant applications, including high density magnetic data storage, magnetofluid, magnetic resonance imaging and biomedical techniques. Enclosure of nanometer-sized magnetic particles in carbon capsules is of particular interest since it is beneficial for protection against hostile chemical environments and for avoiding low proximity phenomena. To date, many research works have been concentrated on the synthesis of CEMNPs [1-3]. However, in these works byproducts such as carbon nanotubes/ nanofibers, carbon nanoparticles and free amorphous carbon formed or the diameter distribution of CEMNPs was uneven as well as the CEMNPs were agglomerated by the coalescence of the outer shells, all these disadvantages would limit their potential applications. Herein, we report a different process for synthesizing carbon-encapsulated Ni nanoparticles with a very narrow distribution of diameters and a considerably less amount of byproducts.