Synthesis of carbon encapsulated nickel nanoparticles by laser ablation in liquid

摘要

Carbon encapsulated nickel nanoparticles (CENNPs) with high purity were fabricated by laser ablation of nickel target in ethanol. The size of CENNPs varies from tens to hundreds of nanometers, and CENNPs show two kinds of typical morphologies i. e. a nickel core with a carbon shell or a nickel core with two carbon shells. Transmission electron microscopy indicated that the CENNPs formed as a result of laser evaporation of the nickel target and the decomposition of ethanol, whose carbon atoms mixed with the nickel vapor, and Ni/C liquid droplets appeared during the cooling stage. The carbon shells formed by precipitation of carbon atoms on the surface of the nickel cores led to the formation of CENNPs.