Removal of Pb(II) using silver nanoparticles deposited graphene oxide: equilibrium and kinetic studies

摘要

Silver nanoparticles-decorated graphene oxide (Ag-GO) composites as advanced metal ion adsorbents have been synthesized. The silver nanoparticles (Ag-NPs) were homogeneously deposited onto graphene oxide (GO) surface by an optimal method, in which N,N-dimethylformamide as a co-dispersant is added to an aqueous suspension of GO and AgNO3. The Fourier transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy indicates that GO and Ag-GO are fully exfoliated. The synthesized Ag-GO NPs were used for removal of Pb(II) metal ions. The experiments showed that the removal of metal ions followed a pseudo-second-order kinetic model and equilibrium adsorption studies confirmed that the Langmuir model provided a better fit than others as revealed by high correlation coefficients and low Chi-square values. These Ag-GO NPs can be successfully used for the separation of Pb(II) from aqueous solutions.