A novel ex-situ charge interaction strategy for the fabrication of graphene oxide/organic functionalized silica nanoparticles composites and application in Cd (II) adsorption

Abstract In this study, a new-style “ex-situ charge interaction” strategy has been developed to prepare graphene oxide/organic functionalized silica nanoparticles (GO/OSNs) composites. The crucial point of the strategy is that the OSNs have positive charge by adding Hydrochloric acid (HCl). Four types of OSNs were prepared via one-pot sol–gel reaction of four different kinds of organosilane. Then the positively charge OSNs and negatively charge GO could effectively composite via charge interaction. The GO/OSNs were characterized by Scanning electron microscope (SEM), Transmission electronic microscope (TEM), Fourier transform infrared (FT-IR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The results showed that “ex-situ charge interaction” strategy might be a general method for the fabrication of GO/OSNs. This research provides a new approach for the fabrication of GO/OSNs composites with other OSNs structures. In addition, the application of GO/OSNs in the adsorption of Cd(II) has also been investigated, which included adsorption properties of four GO/OSNs, parameters of adsorption isotherm and adsorption kinetics. GO/OSNs composites were fabricated based on a new-style “ex-situ charge interaction” strategy. OSNs were first prepared via one-pot sol–gel reaction. Furthermore, they were given positive charge by adding HCl. Finally, GO/OSNs were fabricated by charge interaction of between GO and OSNs.