Graphene Oxide: Graphene Quantum Dot Nanocomposite for Better Memristic Switching Behaviors

• Main Author: Lei Li
• Format: Article
• Language: English
• Published: MDPI AG 2020-07-01
• Series: Nanomaterials
• Subjects: tristable memristic switching; all-inorganic multi-bit memory; charge-trap memristor; GO:GQDs nanocomposite
• Online Access: https://www.mdpi.com/2079-4991/10/8/1448

Tristable memristic switching provides the capability for multi-bit data storage. In this study, all-inorganic multi-bit memory devices were successfully manufactured by the attachment of graphene quantum dots (GQDs) onto graphene oxide (GO) through a solution-processable method. By means of doping GQDs as charge-trapping centers, the device indium-tin oxide (ITO)/GO:0.5 wt%GQDs/Ni revealed controllable memristic switching behaviors that were tunable from binary to ternary, and remarkably enhanced in contrast with ITO/GO/Ni. It was found that the device has an excellent performance in memristic switching parameters, with a SET1, SET2 and RESET voltage of −0.9 V, −1.7 V and 5.15 V, as well as a high ON2/ON1/OFF current ratio (10³:10²:1), and a long retention time (10⁴ s) together with 100 successive cycles. The conduction mechanism of the binary and ternary GO-based memory cells was discussed in terms of experimental data employing a charge trapping-detrapping mechanism. The reinforcement effect of GQDs on the memristic switching of GO through cycle-to-cycle operation has been extensively investigated, offering great potential application for multi-bit data storage in ultrahigh-density, nonvolatile memory.