LAUSR

Copper nanoparticles are considered a promising alternative for silver and gold nanoparticles in conductive inks for the application of printing electronics, since copper shows a high electrical conductivity but is significantly cheaper than silver and gold. In this study, copper nanoparticles were synthesized in the gas phase by transferred arc discharge, which has demonstrated scale-up potential. Depending on the production parameters, copper nanoparticles can be continuously synthesized at a production rate of 1.2~5.5 g/h, while their BET (Brunauer-Emmett-Teller) sizes were maintained below 100 nm. To investigate the suitability in electronic printing, we use ball milling technique to produce copper conductive inks. The effect of ball milling parameters on ink stability was discussed. In addition, the electrical resistivity of copper films sintered at 300 ℃ in reducing atmosphere was measured to be 5.4 ±0.6 µΩ⸱cm, which is about three times higher than that of bulk copper (1.7 µΩ⸱cm). This indicates that conductive inks prepared from gas-phase synthesized copper nanoparticles are competitive to the conductive inks prepared from chemically synthesized copper nanoparticles.