A Study of the Electro-Catalytic Oxidation of Methanol on a Ni-Functionalized Graphene Oxide/p-Type Conductive Polymer Modified Graphite Electrode: Experimental and Theoretical Approach

Resumo

The preparation of Ni-functionalized graphene oxide/poly orthoaminophenol composites (Ni–FGO–POAP) is presented and the composites were used as graphite electrode modifier for methanol electrooxidation in NaOH. Nickel was accumulated by complex formation between Ni(II), in solution and amines sites in the polymer backbone to obtain Ni–FGO–POAP/G electrode. The electrochemical performance of Ni–FGO–POAP composite electrodes was investigated by common electrochemical techniques. The peak on the potentiodynamic curve for Ni–FGO–POAP electrode in alkaline solutions of methanol is observed which is ascribed to the methanol oxidation in alkaline medium. Under the CA regimes the reaction followed a Cottrellian behavior. The results obtained are discussed from the point of view of employment of the Ni–FGO–POAP composites for the catalytic electrodes of fuel cells. In addition, the atoms-in-molecule (AIM) theory is used to study atomic-scale charge/energy transfer in grapheme-like molecular system.