SiO2/graphene composite for highly selective adsorption of Pb(II) ion

SiO2/graphene composite was prepared through a simple two-step reaction, including the preparation of SiO2/graphene oxide and the reduction of graphene oxide (GO). The composite was characterized by UV-Vis spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscope, and X-ray photoelectron spectroscopy, and what is more, the adsorption behavior of as-synthesized SiO2/graphene composite was investigated. It was interestingly found that the composite shows high efficiency and high selectivity toward Pb(II) ion. The maximum adsorption capacity of SiO2/graphene composite for Pb(II) ion was found to be 113.6 mg g(-1), which was much higher than that of bare SiO2 nanoparticles. The results indicated that SiO2/graphene composite with high adsorption efficiency and fast adsorption equilibrium can be used as a practical adsorbent for Pb(II) ion.(C) 2011 Elsevier Inc. All rights reserved.