Synthesis and Characterization of ZnFe₂O₄- PEG/RGO Nanocomposites as Lead Heavy Metal Adsorbents

Abstract

Lead waste that pollutes the environment can cause a variety of serious diseases. Various efforts have been made to remove lead waste from the environment, one of which is through the development of magnetic nanoparticles-based adsorbents. In this work, the synthesis of ZnFe2O4-PEG/RGO nanocomposites was carried out through co-precipitation and sonochemical methods. The structure, morphology, function groups, and adsorption performance of the ZnFe2O4-PEG/RGO nanocomposites were characterized using XRD, SEM, FTIR, and AAS. X-ray diffraction pattern showed the formation of a single phase ZnFe2O4 with a cubic spinel structure. The RGO peak was not detected because the RGO mass was much smaller inside the ZnFe2O4-PEG/RGO nanocomposites. Furthermore, refinement analysis through Rietica software obtained crystallite size of ZnFe2O4-PEG/RGO were 9.6 nm. The SEM result showed that the morphology of ZnFe2O4-PEG tends to be spherically distributed on RGO. Based on FTIR results, the functional groups of ZnFe2O4-PEG/RGO nanocomposites showed the presence of Zn-O and Fe-O bonds at 529 cm-1 and 428 cm-1. Meanwhile, C-O bonds at wavenumbers 1222 cm-1 showed typical absorption of RGO. Despite Fe-O and C-O bonds, the presence of C-O-C bonds at wavenumbers of 1031 cm-1 indicates the characteristics of PEG that successfully coats ZnFe2O4 nanoparticles. Interestingly, the AAS results showed that ZnFe2O4-PEG/RGO nanocomposites had an excellent performance as lead adsorbents, evidenced by the percentage of adsorption up to 97,7%.