Preparation of Pt/poly (2-Methoxyaniline)-sodium dodecyl sulfate composite and its application for electrocatalytic oxidation of methanol and formaldehyde

In this work, poly (2-Methoxyaniline) (P2MA) film was prepared by using successive potential cycling in monomer solution in the presence of sodium dodecyl sulfate (SDS) as an anionic surfactant at the surface of glassy carbon electrode (GCE). Then, electrodeposition at a constant potential (-0.20 V vs. Ag|AgCl|KCl (3 M)) in 0.5 M H2SO4 solution containing 5.0 mM H-2 PtCl6 was performed for dispersion of Pt nano/microparticles for fabrication of the Pt/P2MA-SDS composite. The as-formed Pt/P2MA-SDS/MGCE was characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and electrochemical methods. The SEM studies revealed that the presence of SDS strongly influences the morphology of the polymer film. The electrochemical methanol oxidation reaction was investigated at the Pt/P2MA-SDS/MGCE by cyclic voltammetry and chronoamperometric techniques. The results indicated that the Pt/P2MA-SDS/MGCE in comparison with Pt/MGCE and Pt/P2MA/MGCE exhibits excellent electrocatalytic activity towards the methanol oxidation. The improved performance showed that the P2MA-SDS films significantly increase the effective active surface area of the Pt particles which is due to the synergistic effect between Pt and P2MA-SDS at the electrode surface. Furthermore, the effect of several parameters such as P2MA thickness, 2MA, SDS and CH3OH concentrations towards the methanol oxidation as well as long-term stability of the modified electrode has been investigated. The electrocatalytic oxidation of formaldehyde as an intermediate in the methanol oxidation was also investigated. (C) 2014 Elsevier Ltd. All rights reserved.