Sulphur functionalizion of graphene oxide by radiofrequency plasma

Tailoring the surface properties of graphene oxide by the grafting of heteroatom-based functionalities is mandatory for the applicative purpose. In this context, here, we investigate the grafting of sulphur functionalized graphene oxide surface (GO–XSH) via a plasma-based method. The impact of the treatment on the chemical composition and the morphology of GO–XSH was evaluated combining microscopic (atomic force microscopy) and spectroscopic techniques (X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy). Optimized experimental conditions have been identified, considering Ar/H2S gas mixture, for an efficient grafting of –SH groups on the GO surface. This is explained by the creation of defects by bombarding ions during the treatment, followed by subsequent chemisorption of sulphur-based radicals produced in the plasma. The whole set of our results demonstrates the attractiveness of our strategy for tuning the surface properties of GO of interest for biological applications.