Synthesis of graphene oxide / polydopamine composite for coating on clay substrate for water treatment

Water purification is a vital and essential thing for human life. The presence of pollutants in water is a major threat to the environment and human health. Various materials have been proposed and used for water treatment in recent years. Recent research has shown the potential of two-dimensional materials such as graphene oxide and its composites for water purification. The goal of this project is to make a clay filter coated with graphene oxide / polydopamine composite for water treatment. To achieve this goal, Graphene oxide was synthesized by modified Hummers method and GO/PDA composite were prepared by dopamine self-polymerization in the presence of graphene oxide in weakly alkaline solution and the immersion method was used to cover the substrate. Finally, X-ray diffraction analysis (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR), and field emission scanning microscopy (FE-SEM) results are indicated that graphene oxide and graphene oxide / polydopamine composites are well synthesized and the extent of methylene blue contamination degradation was evaluated by visible-ultraviolet spectroscopy. The results showed that all samples have high potency in absorbing methylene blue pollutants And with the addition of graphene oxide to polydopamine, the absorption rate increased from 63% to 99% due to the increase in oxygen-containing groups. According to cross-sectional scanning electron microscopy images, the applied GO coating was removed from the substrate and by adding PDA to graphene oxide, the stability of the coating on the clay substrate was improved. Using this composite coating on an inexpensive clay substrate , the efficiency of the body increased from 20% to 82% in the first 40 minutes of organic dye absorption.