Evaluation of Microstructural and Antibacterial Properties of Graphene Oxide Synthesized by Green Method

In this research, a fast, environmentally friendly, and low-cost method has been used for the synthesis of large-scale production of graphene oxide. In this process, graphene oxide was synthesized via single-step reforming of sugarcane bagasse agricultural waste by oxidation under muffled atmosphere conditions at 350 ºC and for 15 minutes. The results of Fourier transform infrared spectroscopy and X-ray diffraction analyses confirm the formation of graphene oxide. The results of scanning electron microscopy and atomic force microscopy studies show that the graphene oxide sheets are with few wrinkles, the number of layers is 5-6 layers, the average size of the plate thickness is 5 nm, and the average lateral dimensions of the plates is 500 nm. The synthesized graphene oxide was evaluated by the toxicity test at concentrations of 200, 400, and 600 μg/ml on Gram-positive bacteria, “Streptococcus iniae”, and Gram-negative bacteria, “Escherichia coli” and “Pseudomonas aeruginosa”. The results show that graphene oxide at concentrations of 400 and 600 μg / ml has a toxic and an antibacterial agent for bacteria and it has reduced the growth rate of bacteria. In addition, graphene oxide nanosheets are more toxic to gram-positive bacteria than gram-negative bacteria. The results of differential thermal analysis on sugarcane bagasse show that the formation of graphene oxide in air is at a temperature of 350 °C but it is in argon atmosphere is higher. In addition, the results of the thermal analysis performed on the synthesized graphene oxide in the air atmosphere indicate that its instability begins at 60 °C.