Highly potent radical scavenging-anti-oxidant activity of biologically reduced graphene oxide using Nettle extract as a green bio-genic amines-based reductants source instead of hazardous hydrazine hydrate

Reduced graphene oxide (rGO) is relied upon to be the most promising candidate for high-proficiency. Hydrazine is the most conventional efficient reducing agent that has been frequently used for reduction of graphene oxide, however, it is not environmentally safe due to its toxic nature, causing unsatisfactory defects on the basal plan of GO. Therefore, employing green and efficient reducing agents from natural sources like plant extracts has become the research interest for obtaining high quality reduced graphene oxide sheets in recent years. Here a one-step, easy, cost-effective and green synthesis method based on Nettle leaves' extract has been introduced as an effective reduction method of graphene oxide compared with the toxic and harmful Hydrazine hydrate substance. In this study, GO and rGO were obtained from various methods and characterized by Raman spectroscopy, field emission scanning electron microscope, high-resolution transmission electron microscope (HR-TEM), X-ray diffraction analysis (XRD) and X-ray photon spectroscopy (XPS) analysis. Results of different analytical techniques revealed that the Nettle leaves' extract could successfully reduce GO sheets to high performance reduced graphene oxide with 79% efficiency in comparison with conventional Hydrazine hydrate. On the other side the rGO obtained by Nettle solution could scavenge the free radicals with 70% inhibition capacity at least concentration. Existence of Histamine and Serotonin and many other polyphenols as a part of Nettle leaves composition by following anti-oxidants mechanisms (H donation or electron transfer) promote the anti-oxidant functionality of Nettle leaves. So the highlighted achievement of this paper is to obtain a highly antioxidant green reduced graphene oxide with a wide applications i.e medical and polymer composite with UV-shielding activity.