Ferrocene functionalized graphene: preparation, characterization and efficient electron transfer toward sensors of H2O2

We demonstrate the use of ethylenediamine (ED) functionalized graphene oxide (GO) as the building block in the preparation of ferrocene-graphene nanosheets (Fc-GNs) nanoparticles (NPs) to enhance the electrochemical catalytic ability. The resulting Fc-GNs was characterized by FTIR, AFM, TEM, EDX, and XPS. Furthermore, the electrochemical properties of the Fc-GNs have been investigated in an aqueous solution in detail by preparing Fc-GNs modified glassy carbon electrodes (GCE). One pair of surface-confined redox waves corresponding to the couple of Fc/Fc(+) is obtained, which indicates that Fc grafted in graphene retains electrochemical activity, and electrochemical impedance spectroscopy indicated that the Fc-GNs has perfect electron transfer (ET) properties. Furthermore, it shows excellent mediation of H2O2 based on Fc/Fc(+) used as ET mediators for the oxidation of H2O2 to O-2, suggesting specific properties of Fc-GNs due to a combination of Fc and graphene. An Fc-GNs based sensor for H2O2 is fabricated, and it shows excellent stability and sensitivity. This work not only demonstrates the Fc-GNs as a new kind of functional nanomaterial, but also shows promise in the construction of novel chemical and biosensors.