Fabrication of completely water soluble graphene oxides graft poly citric acid using different oxidation methods and comparison of them

In this paper, graphene oxides graft poly citric acid was synthesized. In first step grahene oxide was prepared. In oxidation process Mildly oxidation technique and a modified Hummer's method which used a lower concentration of oxidizing agent were used to prepare the graphene oxide. Two types of graphene oxides were investigated including Hummer's Graphene Oxide (HGO) and Mildly Graphene Oxide (MGO). Subsequent the surface of graphene oxides were modified by grafting (poly citric acid (PCA)) by using radical polymerization. Polymerized graphene oxides (HGO-graft-PCA and MGO-graft-PCA) were prepared and characterized by using various microscopic and spectroscopic analyses including FTIR, SEM, TEM, UV-Visible, and XPS. The results were consistent with PCA being grafted onto the surface of the graphene oxide. Our results show that polymerization of MGO is better than HGO with the polymerized MGO better able to dissolve in organic and aqueous solvents. Finally, the MGO and MGO-g-PCA were used as nanoelectrocatalysts and coated on electrode surfaces successfully.