Conductive Graphitic Channel in Graphene Oxide-Based Memristive Devices

Electrically insulating graphene oxide with various oxygen-functional groups is a novel material as an active layer in resistive switching memories via reduction process. Although many research groups have reported on graphene oxide-based resistive switching memories, revealing the origin of conducting path in a graphene oxide active layer remains a critical challenge. Here nanoscale conductive graphitic channels within graphene oxide films are reported using a low-voltage spherical-aberration-corrected transmission electron microscopy. Simultaneously, these channels with reduced graphene oxide nanosheets induced by the detachment of oxygen groups are verified by Raman intensity ratio map and conductive atomic force microscopy. It is also clearly revealed that Al metallic protrusions, which are generated in the bottom interface layer, assist the local formation of conductive graphitic channels directly onto graphene oxide films by generating a local strong electric field. This work provides essential information for future carbon-based nanoelectronic devices.