Investigation of methylene blue dye adsorption on nanographite oxide prepared by electrochemical exfoliation

The adsorption properties of nanographite oxide (NGO) prepared by electrochemical exfoliation have been explored using methylene blue (MB) dye. It has been found that NGO adsorbs MB molecules through π–π interaction and proton transfer from the carboxyl group of NGO to the MB molecule. It has been proved that the adsorption process obeys the Freundlich isotherm model and the pseudo-second-order kinetic model, the thermodynamic parameters of which indicate that the process occurs spontaneously, while achieving a dye removal rate of 75 to 98% with a final dye concentration of only 0.005 mg dm−3.