One-step synthesis of SnO2-reduced graphene oxide (SOG) composites for efficient removal of organic dyes from wastewater

Abstract

In this work, SnO₂ was used to functionalize graphene oxide (GO) in order to promote the sorption efficiencies of dyes. The texture properties of the as-synthesized SnO₂/rGO (SOG) nanocomposites were characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and N₂ adsorption–desorption isotherms. The SOG composites exhibited fast adsorption rates toward multiplex dyes. In this paper, we used rhodamine B (Rh B), methylene blue (MB), methyl green (MG) and methyl red (MR) as model organic dye pollutants, and the maximum adsorption capabilities for Rh B, MB, MG, and MR reached 115.4, 72.2, 76.5 and 108.3 mg g⁻¹, respectively. Moreover, the adsorbent could be easily regenerated by washing it with ethanol. The regenerated SOG nanocomposites show a quite stable adsorption performance which can be reused for dye removal. These results demonstrated that the SOG nanocomposites could be used as a good alternative for the effective removal of organic dyes from wastewater in wide pH ranges.