Electrocatalytic Oxidation of Methanol Employing Ni-Al LDH Nanoparticles Decorated polymer Film on a Glassy Carbon Electrode

In the recent years, inorganic layered materials have attracted growing interest for use invarious fields owing to their favorable properties, including low cost, high thermal stability andsuitable catalytic activity. Layered double hydroxides (LDH) belong to a class of anionic clay orhydrotalcite-like clays consist of stacked brucite-type octahedral layers with anions and watermolecules occupying the interlayer spaces, family providing numerous applications due to theirunique physicochemical properties [1]. Electrochemical applications of LDH to electrochemicalsensors, electrocatalysts, dye-sensitized solar cells and super capacitors were presented. In thefuel cell applications, recently Ni-Al LDH has been reported to catalyze the electrooxidation ofprimary alcohols and sugars [2].In this work, for the first time, a promising electrocatalyst was developed based on a layerprocess by electropolymerization of ortho-aminophenol (OAP) on the surface of a nanoporousglassy carbon electrode was constructed as a proper polymeric framework for deposition of Ni-Al LDH nanoparticles. After physicochemical characterizations of Ni-Al LDH /poly(OPA)/nanoporous/ GCE, its electrocatalytic and stability characterizations toward methanol oxidationin alkaline media were investigated in detail by cyclic voltammetry and chronoamperometry.Results showed that, the electrocatalytic activity of the Ni-Al LDH/poly(OPA)/nanoporous/GCEelectrode is much higher than those of unmodified electrode under similar experimentalconditions, showing the possibility of attaining good electrocatalytic anodes for fuel cells.Kinetic parameters such as the electron transfer coefficient (α) and the number of electronsinvolved in the rate determining step (nα) for the oxidation of methanol were determined utilizingcyclic voltammetry (CV).

Keywords:

Ortho-Aminophenol , Electropolymerization , Ni-Al LDH , Nanoporous , Methanol