Synthesis of zirconium carbide (ZrC) nanoparticles covered with graphitic “windows” by pulsed plasma in liquid

Abstract

Cubic phase zirconium carbide (ZrC) nanoparticles encapsulated in graphitic carbon with an average size of about 10 nm were produced using pulsed plasma in liquid (PPL), in which zirconium metal electrodes provided the zirconium source and liquid ethanol the carbon. The quenching effect and near vacuum environment inherent in this pulsed plasma in liquid method resulted in the synthesis of nanoparticles with a uniform small size distribution and high purity. Lattice parameters of the obtained samples refined by the Rietveld method were larger than other reported data. Also, the emission lines of atoms Zr I, ions Zr II, atoms C I, ions C II and atoms H I were observed by an optical emission spectrum to gather information on the synthesis mechanism. The results of thermogravimetric and infrared ray emissivity of the nanoparticles showed that the graphitic carbon shells composed of a mere several layers with high transmissivity serve to act as “windows”, helping both to protect the ZrC nanoparticle inside from oxidation and to preserve its high infrared ray emissivity.