Thesis (M.Eng.)--Chulalongkorn University, 2013

This research presents Cu-Zn nanoparticles synthesis by submerged arc discharge of brass rod (Cu 90%wt/Zn 10%wt) in an ambient atmospheric pressure. Four types of dielectric liquid including deionized water, ethanol, ethylene glycol and diethanolamine were used in arc-submerged nanoparticles synthesis system. The particle size, microstructure and morphology of nanoparticles synthesized were characterized via transmission electron microscopy (TEM), Scanning electron microscope (SEM) and X-ray diffraction (XRD), respectively. The XRD patterns show that the nanoparticles synthesized in deionized water, ethanol and ethylene glycol consist of Cu-Zn alloy and zinc oxide. Zinc oxide was formed by oxygen free radicals during decomposition of the dielectric liquids used. In contrast, the XRD pattern of the nanoparticles synthesized in diethanolamine show peaks of only Cu-Zn alloy. Thus, formation of zinc oxide can be prevented by using diethanolamine as dielectric liquid. The nanoparticles synthesized were spherical with size ranging from 10 nm to 40 nm. The nanoparticles synthesized in diethanolamine were mixed with ammonia, deionized water and silver oxide to prepare a conductive ink. The conductive ink formulated was screen printed on polyethylene terephthalate (PET) substrate. The resistivities of the patterns obtained were then measured by LCR meter. By baking the printed pattern in air at 150 C for 60 min, the lowest volume resistivity of the printed pattern is 190 µ.cm.