Removal of methylene blue from aqueous solution with self-assembled cylindrical graphene-carbon nanotube hybrid

In this study, we report the efficient removal of organic dye from aqueous solution with a self-assembled cylindrical graphene-carbon nanotube (G-CNT) hybrid which can be directly fabricated by a simple one-step hydrothermal process. The hybrid showed good performance for the removal of methylene blue (MB) from aqueous solution with a maximum adsorption capacity of 81.97 mg g(-1). The removal efficiency was found to be 97% at the initial MB concentration of 10 mg L-1. The kinetics of adsorption followed the pseudo-second-order kinetic model, while the Freundlich adsorption isotherm was applicable to describe the equilibrium adsorption process. This study suggests that carbon-based hybrid could be explored as a new adsorbent for removing organic dye pollutants from aqueous solution. (C) 2012 Elsevier B.V. All rights reserved.