An innovative green approach to the production of bio-sourced and nano-sized graphene oxide (GO)-like carbon flakes

Abstract In this study, we developed a green and facile top–down approach for the production of nano-sized graphene oxide (GO) like flakes from natural sources by sonochemistry. The long carbon flakes produced by the pyrolysis of waste onion sheathing were then converted into uniform nano-sized GO-like flakes (6.6 ± 2.4 nm) by sonication in deionized water. The effect of time on the size of GO-like nanostructures obtained by ultrasonication of bio-sourced carbon flakes has been extensively investigated. Transmission electron microscopy (TEM) and atomic force microscopy (AFM) were used to determine the size of these nanostructures. The changes in the surface chemical composition of the nanostructures during the sonochemical treatment were analyzed by X-ray photoelectron spectroscopy (XPS). Furthermore, cytotoxicity and hemocompatibility of nano-sized GO-like flakes were evaluated. Pyrolysis of waste onion sheathing followed by sonication could therefore be explored as a highly cost-effective, eco-friendly, uncomplicated, green, and efficient way of producing large-scale nano-sized GO-like carbon flakes.