▎ 摘　　要

In this paper, graphene oxide-bismuth tungstate (GO-Bi2WO6) nanocomposite was synthesized and used as an efficient and green adsorbent for the removal of Pb2+. Bi2WO6 nanoplates were synthesized by the co-precipitation method and then used for modifying of graphene oxide. To characterize of the synthesized adsorbent, Fourier-transform infrared spectrophotometry (FT-IR), field emission scanning electron microscopy (FESEM), electron-dispersive X-ray spectroscopy (EDX) and X-ray diffraction spectroscopy (XRD) were used. By optimization of critical parameters including pH of sample solution, amounts of adsorbent and contact time, it was revealed that pH = 5.0, 20 mg adsorbent and 20 min contact time provide above 94% removal percentage for 50 mg L-1 Pb2+. Different adsorption isotherms including Langmuir, Freundlich, Temkin and Dubinin-Radushkevich were investigated, and the results show that the adsorption of Pb2+ followed by the Freundlich isotherm with a maximum adsorption capacity of 128 mg g(-1). Also, interpretation of different kinetic models shows that adsorption of Pb2+ is followed by the pseudo-second-order kinetic model. Finally, the results of thermodynamic analysis show that adsorption of Pb2+ onto the GO-Bi2WO6 nanocomposite is endothermic and spontaneous process (Delta H > 0, Delta G < 0) and desirable at higher temperatures.