▎ 摘　　要

In this study, 3-aminopropyltriethoxysilane-functionalized graphene oxide (AS-GO) was synthesized by one-step refluxing of graphene oxide (GO) with 3-aminopropyltriethoxysilane (AS). The properties of GO and AS-GO were characterized by scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), atomic force microscopy (AFM), Fourier transform infrared spectrum (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Specific surface area and Zeta potential. Various factors, such as solution pH, initial Cr(VI) concentration, contact time, temperature and coexisting anions, were analyzed during the adsorption process. The results showed that the Cr(VI) adsorption onto AS-GO was highly pH dependent, and the maximum adsorption capacity reached up to 215.2 mg/g at 328 K. Experimental data, obtained from adsorption kinetics and adsorption isotherms studies, could be well fitted by Langmuir adsorption isotherm and pseudo-second-order model. The XPS, FT-IR, and EDS analysis revealed that Cr(VI) removal might be attributed to the Cr(VI) adsorption on surface functional groups (protonated amine groups and Si OH groups) and the reduction of Cr(VI) to Cr(III). These results demonstrated that AS-GO could be a promising adsorbent for Cr (VI) removal from wastewater. (C) 2017 Elsevier B.V. All rights reserved.