Poly(vinyl) Alcohol-Assisted Fabrication of Magnetic Reduced Graphene Oxide Aerogels and their Adsorption Performance for Cd(II) and Pb(II)

Magnetic graphene-based aerogels have attracted intensive interest due to their unique properties. In this study, a two-step strategy was proposed to fabricate a family of magnetic reduced graphene oxide aerogels (abbreviated as rGO/Fx, x = 1, 2 and 3) as adsorbents for removing heavy metals from water. The hydrogen bonds between poly(vinyl) alcohol (PVA) and rGO maintained the integrity of the rGO/Fx structures evidenced by FT-IR and Raman spectra. The rGO/Fx showed a unique structure with nanoparticles/nanoplates embedded on rGO sheets by SEM observation. The rGO/Fx consisted of PVA, rGO and Fe-based species (Fe3O4, Fe-0 and FeOOH) identified by PXRD, TGA and XPS analysis. The impressive magnetic property of rGO/Fx can be easily tuned by the mass ratio of Fe/GO. The saturation magnetizations were 0.50, 0.72, and 9.59 emu/g for rGO/F1, rGO/F2 and rGO/F3, respectively. The capacity of rGO/F1 was calculated to be 21.84 and 16.10 mg/g for Cd2+ and Pb2+, respectively. This study may contribute a novel synthesis method of magnetic graphene aerogels by using polymers and metals, and offer an alternative adsorbent for removing heavy metals.