While plastics are typically electrical insulators, the addition of conductive particles can transform them into electrical conductors. Using a combination of experimental and simulation methods we have established how particle orientation and shape dictate the electrical properties in polymer nanocomposites with carbon nanotubes or silver nanowires. Moreover, we discovered an unexpected response in the silver-nanowire/polymer-composites, namely electrical resistive switching. Upon the application of an electric field, the nanocomposites change from insulating to conducting. At room temperature, resistive switching is reversible. We have proposed a metal filament formation mechanism for this phenomena, and experiments are underway to evaluate this hypothesis and to explore device applications for this novel switch.
Silver nanowires produced by electroplating into alumina templates were combined with polystyrene to fabrication polymer nanocompoistes. Electrical resistive switching demonstrated by recording the conductivity as the applied voltage jumps from below to above the switching voltage. This particular sample was successfully switched more that 42,000 times. Schematic shows the mechanism of metal filament formation between silver nanowires.
