Graphene as a template and structural scaffold for the synthesis of a 3D porous bio-adsorbent to remove antibiotics from water

A graphene-soy protein (GS) aerogel was prepared by a simple thermal reduction method and then used as an adsorbent for the removal of antibiotics. The GS aerogel was characterized by an optical contact angle meter, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman, Branauer-Emmett-Teller (BET) and Fourier transform infrared spectroscopy (FTIR). In GS, graphene acts as a template that loads onto the surface of the protein through hydrogen bonds to form a layered bulk unit and interacts with each other to form self-assembled hydrogels. Moreover, graphene interacts well with protein without obvious structural damage and does not agglomerate. The resulting GS has a high specific area of 30.07 m(2) g(-1) with abundant microspores and excellent hydrophilic properties, which lead to excellent adsorption properties for tetracycline (500.0 mg g(-1)) and ciprofloxacin (500.0 mg g(-1)). This result suggests that the small quantity of graphene assisted the protein to form an excellent bio-adsorbent.