Oxidative debris in graphene oxide: a decade of research

Abstract

Graphene oxide (GO) is at the center of a multitude of applications in different fields of nanotechnology. The increasing use of GO has led to its massive commercialization, which requires rigorous quality control that assures its properties and safety. However, both GO properties and safety are very dependent on the presence, quantity, and type of impurities, and one type of particular impurity frequently neglected in GO research is oxidative debris (ODs). ODs are highly oxidized nanometric carbonaceous fragments produced during GO processing. They adhere to the GO flake surfaces via non-covalent interactions and are present even in samples purified by standard methods. ODs have been extensively reported to impact the properties of carbon nanotubes, but their effects remain relatively overlooked for GO. Here, a decade of scientific research on ODs in GO is reviewed, covering aspects that include the emergence of ODs in the GO synthesis, the protocols for their removal and isolation, the ODs’ structural and chemical composition, and more importantly their influence on several GO properties, such as electrical, electrochemical, adsorptive, biological, toxicological, among others. This review aims to stimulate the debate and further investigations on such an intriguing topic, ultimately contributing to a deeper understanding and application of GO.