Highly stable self-passivated MoO3-doped graphene film with nonvolatile MoO layer

Abstract

The realization of high-performance graphene-based electronics, including transparent electrodes, flexible devices, and energy storage, is often hindered by the lack of adequate doping, which provides a stable and low sheet resistance. In this study, we demonstrate a highly stable MoO 3 -doped graphene obtained simply through a self-passivation. Graphene deposited with a 5-nm-thick MoO 3 exhibited a significant decrease in sheet resistance upon annealing at 400 °C under a hydrogen atmosphere. Surface and structural analyses confirmed that MoO 3 was converted to MoO x by thermal annealing, which consisted of mainly crystalline MoO 3 and Mo 4 O 11 with coexisting MoO 2 . A field-effect transistor fabricated using the MoO x -doped graphene exhibited a p-type characteristic similar to that of the MoO 3 -doped graphene. However, unlike the MoO 3 -doped graphene severely degraded by environment, the MoO x -doped graphene exhibited stable electrical properties after air exposure and chemical immersion owing to the chemically inert Mo 4 O 11 and MoO 2 acting as passivation layers while maintaining the p-type doping by MoO 3 . Thus, we expect that the highly stable MoO x -doped graphene obtained via the simple method will facilitate the fabrication and contribute to the performance reliability of various graphene-based electronic devices. • Highly stable MoO 3 -doped graphene through self-passivation by oxygen deficient MoO x • Simple way of thermal annealing for the synthesis of oxygen deficient MoO x -doped graphene • MoO x -doped graphene with p-type semiconducting characteristics • Excellent stability and chemical durability of MoO x -doped graphene