Abstract
A hydrothermal approach was followed to make highly exfoliated MoS2 nanosheets with hexamethylenetetramine as the exfoliating agent. The synthesized MoS2 nanosheets have a petal-like structure, as evidenced by scanning electron microscopy and transmission electron microscopy. Using this MoS2 nanosheet, various adsorption isotherm and kinetic models were studied to remove contaminants such as tartrazine dye and mercury in the aqueous solutions. The Freundlich isotherm model, which yields the best match, implicates the multilayer adsorption process. In this study, pseudo-first-order kinetics was found to be a good fit indicating the physisorption process for tartrazine dye adsorption and pseudo-second-order kinetics for mercury ion adsorption. Also, it was noticed that MoS2 nanosheets had eliminated 99% of the tartrazine dye and mercury from the aqueous solution within 5 min and 6 h intervals of time, respectively. The maximal adsorption capabilities for tartrazine dye and mercury ions were 41 and 495 mg g(-1), respectively.