Sunlight-Induced Selective Photocatalytic Degradation of Methylene Blue in Bacterial Culture by Pollutant Soot Derived Nontoxic Graphene Nanosheets

Herein, a potential approach is described for assessing the ecological importance of the graphitic nanocarbons isolated from dirty, dangerous black pollutant particulate material. A simple experiment of photodegradation and a toxicological test were done using the natural sunlight as a source of energy and the pollutant petrol soot derived water-soluble graphene nanosheets (wsGNS) as photocatalyst to achieve complete degradation of pollutant organic dye as methylene blue (MB). Compared to the artificial source of visible light (60W tungsten bulb), the sunlight-induced photodegradation using wsGNS show 1.5 times higher rate of photodegradation. The toxicological test confirmed the nontoxic behavior of wsGNS against the two different types of bacterial strains: Gram-negative and Gram-positive cells, Escherichia coli and Staphylococcus aureus, respectively. Moreover, wsGNS are precisely used for the selective photodegradation of MB without harming the bacterial growth from the pool of MB-bacterial strains. Nontoxicity and selectivity along with the improved in photodegradation efficiencies by wsGNS under the influence of sunlight are the most significant and sustainable perspectives of the present finding.