Synthesis of oxygen functional group-controlled monolayer graphene oxide

Graphene oxide (GO) contains various types of oxygen functional groups (e.g., COH, COC, C=O, and O=COH groups), which provide superior functions such as proton conductivity, catalytic activity, and selective absorption. In contrast, the complex structure of GO complicates control over its function; therefore, GO with a simple and/or uniform structure is desired.

epoxy groups, was successfully prepared by exfoliating graphite oxide prepared using Brodie’s method. The monolayer ratio of GO reached 99.2%, and the nanosheets were stable in water for 1 month. Fourier transform infrared, X-ray photoelectron spectroscopy, and temperature-programmed desorption analyses indicated that most oxygen functional groups on GO were epoxy groups. Further, it was determined that GO had structural regularity over a wide range and small amounts of lattice defects despite being oxidized. This means that the developed GO can potentially advance considerably GO studies by replacing previous GO.