Stacking-Specific Reversible Oxidation of Bilayer Graphene

Abstract

We report, for the first time, that the oxidation of bilayer graphene (BLG) can be reversibly and stacking-specifically controlled. The infrared (IR) absorption, IR nanoscopy, and Raman spectroscopy measurements on BLG consistently show reversible changes in the spectra and images upon exposure to O 2 and H 2 at elevated temperatures. We also obtain spectroscopic and theoretical evidence that stacking orders of graphene layers have a profound influence on the oxide structures: AB-BLG reacting with singlet and triplet oxygen results in endoperoxides (−C−O−O− C−), whereas AA′-BLG reacting with oxygen generates both the epoxides (singlet, −C−O−C−) and endoperoxides (triplet). We believe that our result provides deeper understanding on the layer-dependent catalytic activities of graphene, which is crucial for the design of high-performance graphene-based catalysts needed for various electrochemical, biological, and environmental applications.

Graphene/MoS2−xOx/graphene photomemristor with tunable non-volatile responsivities for neuromorphic vision processing

“…It should be noted that CVD-grown graphene contained grain boundaries and bi-graphene islands with an average density of ~3 × 10 6 cm -2,38 , which contributed to the oxidation of graphene electrodes during the deposition of MoS 2 and the formation of MoS 2-x O x (Figs. S3-S6, Supplementary Information) [38][39][40] .…”