Fabrication of reduced graphene oxide decorated with CuS nanoparticles and its activity toward the adsorption of methylene blue

Reduced graphene oxide (RGO) can act as an adsorbent because of its high surface area. The adsorptive characteristics of a RGO composite combined with CuS were studied quantitatively. The removal efficiency of Methylene Blue was found to be about 85 %, which is higher than that of bare CuS (approximate to 73 %). Furthermore, the kinetics of adsorption of Methylene Blue was inspected to determine the rate of the process. The removal process was faster with the RGO-CuS system than with bare CuS. Both high and low temperatures were not favorable for this adsorption process. In highly ionic media of high or low pH, the adsorption was greater than in media of neutral pH. Thermodynamic parameters were calculated in this study and they suggest that this is physisorption and exothermic in nature.