Fabrication of polyaniline/silver nanoparticles/multi-walled carbon nanotubes composites for flexible microelectronic circuits

Flexible microelectronic circuits were fabricated via the screen-printing technique using ternary composites of polyaniline, silver nanoparticles, and multi-walled carbon nanotubes (PANI/Ag/MWCNTs) with protonation of dodecyl benzenesulfonic acid. These ternary composites were prepared by in situ polymerization of PANI on Ag/MWCNT binary composites, which were synthesized prior by ultrasonication of AgNO3 in ethylene glycol solution dispersed with MWCNTs. In the process of synthesis, the ratio of the reactants (aniline to Ag/MWCNTs) could influence the microstructures and morphologies of the PANI layer, which would then significantly affect the conductivity of the composites. By tuning this ratio, the conductivity of the composites could be controlled between 10−8 and 2.4 × 102 S cm−1. Meanwhile, the existence of a PANI functional layer increased not only the dispersities but also the processabilities of the composites, and accelerated the preparation of the ternary composites into conductive patterns. Finally, well-defined patterns were fabricated by depositing the ternary composites on different flexible substrates using the screen-printing technique.