The preparation of water-dispersible graphene oxide/conjugated polymer nanocomposite and the nonvolatile resistive switching memory properties

In this article, we have carried out the polymerization of vinyl imidazole and pyrrole by using graphene oxide (GO) as photoinitiator, aiming to obtain a new nanocomposite for fabricating functional devices through solution processing. The structures of the as-synthesized ternary GO–polyvinyl imidazole–polypyrrole (GO–PVim–PPy) composite were studied by specular reflection infrared spectroscopy, transmission electron microscopy, atomic force microscopy and ultraviolet–visible spectrophotometer. The as-synthesized composites show the good water dispersibility which is generated from the structures of the composites. Raman spectroscopy and X-ray photoelectron spectroscopy were used to analyze the properties of the material interface. Moreover, by using the ternary composite as the active layer, the memory devices with the sandwich structure of Al/GO–PVim–PPy/ITO were fabricated by the spin coating. The prepared devices exhibit the nonvolatile resistive switching memory properties with the ON/OFF-state current ratio reaching 106 and the retention time exceeding 104 s. The charge transport characteristics at ON-state and OFF-state were studied by analyzing the current–voltage curves.