Preparation of Cu nanoparticles by a pulsed wire evaporation process for conductive ink applications

In the present study, Cu colloidal nanoparticles and nanopowders were successfully synthesized by a pulsed wire evaporation process. Cu-based nano-inks were prepared by mixing Cu nanoparticles with acrylic resin and solvent. Cu nanoparticles with a particle size of <20 nm were uniformly dispersed in ethylene glycol. The Cu nanopowders were successfully coated with an organic solvent composed of a hydrocarbon compound. This organic coating effectively inhibited the oxidation of Cu nanopowders. In addition, the stability of dispersion of Cu nanoparticles in the inks was improved by a ball-milling process. The electrical conductivity of the prepared Cu nano-inks was 10-28 µS cm^-1 for 20-40 wt% of Cu.