Electrochemical Hydrogenation of Dimensional Carbon

The hydrogen adsorption and electrochemical properties of epitaxial graphene (EG) grown on silicon carbide (SiC) and bulk graphite in dilute sulfuric acid (H2SO4) and perchloric acid (HClO4) solutions were investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). According to EIS, electrochemical activity is dependent on starting I(D)/I(G) ratio suggesting a dependence on point defects in the material for successful hydrogenation. Electrochemical hydrogen loading and unloading on epitaxial graphene was also demonstrated and confirmed by Raman spectroscopy and CV. These results show that hydrogenation of graphene is electrochemically reversible and history dependent impacting H loading. This process demonstrates a new pathway to hydrocarbon bond formation for synthesis of advanced organic/inorganic carbon-based compounds.