Flexible random resistive access memory devices with ferrocene–rGO nanocomposites for artificial synapses

Abstract

Random resistive access memory (RRAM) devices with a simple structure, low power consumption, and tunable switching behavior have emerged as promising candidates to simulate biological synapses. Here, we demonstrate solution-processable RRAM devices with FeC–rGO nanocomposites by intercalating nano-aggregating ferrocenes (FeCs) between the reduced graphene oxide (rGO) sheets, in which FeCs anchor on the surface of rGO through π–π stacking interactions. The Al/FeC–rGO/ITO devices fabricated by spin-coating exhibit a low SET/RESET voltage of −1.7 V/+2.1 V and a high ON/OFF ratio of 10⁸, which results from the formation/rupture of conductive paths between rGO sheets gated by the redox of FeCs. Besides, the devices show high repeatability, excellent durability and favorable flexibility. In addition, the obtained device can be utilized to simulate the potentiation and depression of synapses by applying a pulse voltage below V_SET, further contributing to image pattern recognition. Thus, this approach aims to fabricate information storage devices for future use in artificial intelligence.