Polyaniline Nanofiber/Gold Nanoparticle Nonvolatile Memory

TLDR

The study introduces a novel memory device that merges conducting polymer nanofibers with gold nanoparticles to achieve unique functionality. The memory device consists of a plastic composite film of polyaniline nanofibers decorated with gold nanoparticles sandwiched between electrodes, where an applied bias induces charge transfer from the polymer to the nanoparticles, enabling ON/OFF states differing by three orders of magnitude. The device demonstrates nonvolatile memory with ON–OFF switching times below 25 ns, retention lasting several days, and successful write–read–erase cycles.

Abstract

A nonvolatile plastic digital memory device based on nanofibers of the conjugated polymer polyaniline decorated with gold nanoparticles is reported. The device has a simple structure consisting of the plastic composite film sandwiched between two electrodes. An external bias is used to program the ON and OFF states of the device that are separated by a 3-orders-of-magnitude difference in conductivity. ON−OFF switching times of less than 25 ns are observed by electrical pulse measurements. The devices possess prolonged retention times of several days after they have been programmed. Write−read−erase cycles are also demonstrated. The switching mechanism is attributed to an electric-field-induced charge transfer from the polyaniline nanofibers to the gold nanoparticles. The active polymer layer is created by growing nanometer size gold particles within 30-nm-diameter polyaniline nanofibers using a redox reaction with chloroauric acid. This device combines two exciting research areasnanoparticles and conducting polymersto form a novel materials system with unique functionality.