Exfoliation by cavitation of carbon spheres from green sources, an option to graphene oxide synthesis

Abstract BACKGROUND The production of graphene oxide (GO) from carbon structures by cavitation represents a clear advantage over other alternatives that require a strong oxidation process. The carbon spheres (CSs), used for GO synthesis, were synthesized by chemical vapor deposition (CVD) using two precursors as carbon sources, one recycled and the other green, applying the principles of green chemistry. It has been observed that these materials do not require subsequent treatments for functionalization. This characteristic reduces the risk of handling‐related hazards and minimizes environmental impact. RESULTS A reduction in crystal size from the CSs obtained from expanded polystyrene (EPS) was up to 55.95%. The reduction in the number of graphene layers in the CSs was represented by an increase in the G′ band; the flakes presented the functional groups found in functionalized carbon nanostructures (CNs) OH, CC, and CO. CONCLUSIONS The outer layers of the CSs, obtained from two different precursors, were successfully separated, yielding GO flakes of different thicknesses and numbers of graphene layers. This method signifies an eco‐friendly alternative for obtaining the GO structure from CSs that have been previously synthesized. © 2026 Society of Chemical Industry (SCI).