Fabrication of Electrochemically Reduced Graphene Oxide Films on Glassy Carbon Electrode by Self-Assembly Method and Their Electrocatalytic Application

We report a simple, facile, and reproducible method for the fabrication of electrochemically reduced graphene oxide (ERGO) films on glassy carbon electrode (GCE) by the self-assembly method. The graphene precursor, graphene oxide (GO), was self-assembled on GCE through a diamine linker which was preassembled on GCE by electrostatic interaction between the positively charged amine and the negatively charged layers of graphene oxide (GO). The oxygen functional groups present on the surface of GO were electrochemically reduced to retain the aromatic backbone of graphene. The attachment of GO followed by its electrochemical reduction was confirmed by ATR-FT-IR spectroscopy, Raman spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and scanning electron microscopy (SEM). Raman spectra show that the intensity ratio of D and G bands was increased after the electrochemical reduction of GO. XPS results reveal that the carbon-to-oxygen ratio was increased after the electrochemical reduction of electrostatically assembled GO. Further, Raman and XPS results confirm the removal of oxygen functional groups present on the surface of GO after electrochemical reduction. Impedance spectral studies show that the electron transfer reaction was facile at ERGO modified GCE. Finally, the electrocatalytic activity of ERGO was examined by studying the oxidations of ascorbic acid (AA), dopamine (DA), and uric acid (UA). It enhanced the oxidation currents of AA, DA, and UA when compared to bare GCE. The electrocatalytic activity of the present modified electrode was highly stable.