▎ 摘　　要

Efficient containment and capture of uranium (U(VI)) from aqueous solution is an essential component to ensure socially and environmentally sustainable development. Herein, the three-dimensional graphene/titanium dioxide composite (3D GA/TiO2) was synthesized and applied as an effective adsorbent to remove U(VI) from wastewater as a function of contact time, temperature, pH and ion strength. The 3D GA/TiO2 material was characterized by X-ray diffraction, Raman spectroscopy, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The batch experiments results indicated that the adsorption of U(VI) on materials were fitted with the pseudo-second order kinetics and Langmuir models. More specifically, 3D GA/TiO2 (441.3 mg/g) was observed to outperform the GO (280.0 mg/g), rGO (140.9 mg/g) and TiO2 (98.5 mg/g) at pH 5.0, which was attributable to the excellent cooperative effects. Furthermore, XPS analyses and DFT calculations confirmed the formation of surface complexes between oxygen-containing group and U(VI) with the U-O bonds length of 2.348 angstrom (U-O1) and 2.638 angstrom (U-O2). Meanwhile, the adsorption energy was calculated to be 1.60 eV, which showed a very strong chemisorption during the interaction process. It is believed that the 3D GA/TiO2 revealed good removal performance for uranyl ions, which showed a great potential application to control the nuclear industrial pollution. (C) 2019 Published by Elsevier Ltd.