Fabrication of Amino-Functionalized Magnetic Graphene Oxide Nanocomposites for Adsorption of Ag(I) from Aqueous Solution

In this study, amino-functionalized magnetic graphene oxide (Fe3O4/GO-NH2) nanocomposites were fabricated by one-pot solvothermal method. As-prepared Fe3O4/GO-NH2 nanocomposites were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), nitrogen adsorption/desorption isotherm, elemental analysis, and vibrating sample magnetometer (VSM). Adsorption behaviors of Fe3O4/GO-NH2 nanocomposites for Ag(I) in aqueous solution were investigated. Detailed adsorption studies demonstrate that Ag(I) was reduced to silver in the process of the adsorption by Fe3O4/GO-NH2 nanocomposites. The pH value of aqueous solution had a major impact on Ag(I) adsorption. The maximum adsorption capacity of Fe3O4/GO-NH2 nanocomposites for Ag(I) was 114.90 mg/g. The adsorption process of Fe3O4/GO-NH2 nanocomposites for Ag(I) was well described by the pseudo-second-order kinetics model and the Langmuir isotherm model.