Formation of Graphene Oxide Nanoscrolls in Organic Solvents: Toward Scalable Device Fabrication

Abstract

In this work, formation of graphene oxide (GO) nanoscrolls in organic solvents was investigated upon dispersing GO nanosheets in organic solvents by sonication. It was found that, in some of the organic solvents, the single-layer GO sheets can effectively curl onto themselves to form the nanoscrolls that then sediment under gravity from the dispersion media. The sedimentation was monitored by UV–vis spectroscopy when the GO suspensions were left aside for different time periods after the sonication. The nanoscrolls were separated and characterized by transmission electron microscopy (TEM) and electron diffraction (ED). A typical solvent with such scroll-forming function is pyridine, where 82% of the GO sheets form the GO nanoscrolls and undergo the sedimentation. Scroll formation is also observed for N,N-dimethylformamide (DMF), methanol, ethanol, isopropyl alcohol, acetic acid, and isobutyric acid, but the yields vary with the solvents. The scrolls formed in pyridine suspension show the average length ov...