Controlled synthesis various shapes Fe3O4 decorated reduced graphene oxide applied in the electrochemical detection

The various shapes Fe3O4 decorated reduced graphene oxide (Fe3O4/rGO) were prepared by one-step solution co-precipitation method, in which the shapes (sphere, rod and band) of Fe3O4 in the nanocomposites could be carefully controlled by adjusting the mole ratio of Fe2+/Fe3+ in the presence of rGO modified PVP. The structure of Fe3O4/rGO was characterized by SEM, EDS, TEM and Raman. Furthermore, the band Fe3O4/rGO modified glassy carbon electrode (GCE) was characterized by cyclic voltammetry (CV) and electrochemical impedance spectra (EIS). And the effect of shapes of Fe3O4 decorated reduced graphene oxide on the electrochemical detection of Pb(II) was investigated in detail. It was found that the shape of Fe3O4 had great effects on sensitivity. The band Fe3O4/rGO modified electrode toward Pb(II) showed high sensitivity (13.6 μA/μM), which was higher than that of spherical and rod Fe3O4/rGO modified electrode, respectively. The band Fe3O4/rGO was further demonstrated to be useful for the individual electrochemical detection of Cd(II) and Cu(II) in water for the first time. This report provides an opportunity to study relationship between the shapes and properties of Fe3O4 decorated reduced graphene oxide with high performance.