Study On The Preparation And Application Of Metal Nanoparticles-based Conductive Inks

With the development of printed electronics, the preparation of conductive inks has attracted more and more researchers’ attention. Because of excellent electrical conductivity, high resolution and other advantages, metal nanoparticles-based conductive ink that can be used in transparent conductive films, RFID tags and some other fields has become a hot research spot. In our work, we obtained silver nanoparticles, copper nanoparticles, silver/copper composite nanoparticles in a two-phase system, and studied their morphology, particle size, phase and thermal weight loss. We also attempted to prepare conductive inks with those nanoparticles that we had prepared, and coated slides with our inks, then sintered the slides and investigated the metal films’ conductivity under different sintering temperature. Finally, we prepared transparent conductive film using emulsion self-assembly method with the conductive ink as oil phase, and studied its electrical conductivity and transparency after sintering. The main conclusions are as follows:(1) Obtained spherical oil soluble silver nanoparticles with good dispersibility and high stability, which size is 2～20 nm. The silver films’ resistivity decreases obviously with the increase of sintering temperature. When the temperature is 400℃, the resistivity of silver film is 7.8μΩ·cm, about five times of massive silver resistivity.(2) Obtained oil soluble copper nanoparticles, which size is 2～20 nm and thermal weight-loss rate is as high as 55%. The high weight loss rate shows that coated sodium oleate accounts for a large proportion in the product, which is not conducive to the preparation of copper conductive ink. Considering the advantages of silver and copper, we obtained oil soluble silver/copper composite nanoparticles, which size is 2～30 nm and thermal weight-loss rate is 11.5%, much lower than pure copper nanoparticles’. When the sintering temperature is 400℃, the film’s resistivity is 9μΩ·cm.(3) Obtained transparent conductive film by emulsion self-assembly, which has random network structure. The square resistance of the conductive film is about 20-30Ω and its luminousness is 55%～65%.