Facile and large-scale fabrication of Ni nanochains by a chemical reduction method with the assistance of external magnetic field

摘要

Magnetic Ni microanostructures with controlled morphology have drawn intensive attention due to their interesting physicochemical properties and potential applications in microanodevices. In this study, one-dimensional Ni nanochains with an average diameter of about 140 nm were prepared by a magnetic-field-assisted chemical reduction of Ni~(2+) with hydrazine hydrate free of any template or surfactant. It was found that the morphology and the size of the Ni chains could be adjusted by changing the complexant used in the synthesis. The usage of surfactant in the synthesis would retard the firm connection of Ni nanoparticles and thus resulted in the formation of Ni nanochains consisting of loosely aggregated Ni nanoparticles. The magnetic measurement at room temperature indicated that the coercivity of the Ni sample reached 133.2 Oe, which was much higher than that of bulk Ni metal.