Eco-Friendly Mechanochemical Approach to Magnetic Graphene Oxide: A High-Efficiency Sorbent for Environmental Pollutant Removal.

Graphene oxide (GO) is a nanomaterial with excellent physico-chemical properties widely used in a high variety of technological applications. However, conventional protocols for GO preparation rely on wet synthesis, involving extreme chemical conditions. Recently, mechanochemical synthesis has been postulated as a rapid and sustainable dry alternative for the preparation of new materials. In this work, an optimization of the mechanochemical synthesis of GO from graphite is carried out. To characterize the materials, transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-Ray photoelectron microscopy (XPS), elemental analysis, and nitrogen adsorption-desorption isotherms are employed. The GO synthesized via dry protocol (d-GO) and GO prepared via wet synthesis (w-GO) are coupled with magnetic nanoparticles (MNPs) to prepare magnetic graphene oxide sorbents (d-M@GO and w-M@GO). Subsequently, the adsorption properties of the prepared materials toward inorganic and organic pollutants are determined and compared. The results indicated excellent adsorption efficiency for d-M@GO, demonstrating the successful application of the mechanochemical method in magnetic sorbents preparation. To the best of the available knowledge, this is the first work to investigate the applicability of dry mechanochemical GO for the synthesis of a magnetic sorbent (d-M@GO) and its use toward emerging concern and priority pollutants (PFAS and metal ions).