This study is probing into kinetic influences in silver-copper replacement reactions. In order to develop a high conductivity Cu ink fired in air, copper powder contacts are formed through silver nanoparticles. Silver nanoparticles melt at 200 °C a lower temperature than the oxidation of copper powder. This mechanism can not only prevent copper from oxidized, but also enhance the conductivity. Silver-copper powder is prepared by a replacement reaction. Through changing the content of silver nitrate, the content of dispersant (PVP), reaction time and reaction temperature, the results show that replacement reactions have an impact on the grain size. This study shows that when the molar ratio of silver nitrate to copper powder is 1:0.5, using ethylene glycol as solvent, adding 0.5 wt.% PVP, at room temperature, the reduction rate of silver particles could be controlled, and forming nanostructure silver which has an obvious branch structure. The dendritic structure silver formed smaller branch structures. When reaction time is 30 minutes, there is enough time to produce silver nanoparticles as well as an obvious dendritic structure. On the other side, if the temperature of reaction is too low, copper powder can't be coated completely. A weight percent of silver is more than 95% on the surface by energy dispersive spectrometer analysis. This result shows silver nanostructure covered on copper in a good shape.
All Science Journal Classification (ASJC) codes
- Biomedical Engineering
- Materials Science(all)
- Condensed Matter Physics