Electrochemical synthesis of Pd supported on PANI-MWCNTs-SnO2 nanocomposite as a novel catalyst towards ethanol oxidation in alkaline media

Suitable electrocatalyst support materials with improved catalytic activity, long-time stability and durability are the most important parts of fuel cells. This study explains synthesis of polyaniline-multiwalled carbon nanotubes-tin oxide (PANI-MWCNTs-SnO2) on titanium (Ti) mesh substrate by the facile electrodeposition method for its use as a novel support for palladium (Pd) catalyst. The surface morphology and composition of prepared electrodes were investigated by means of field emission scanning electron microscopy (FESEM), FT-IR (Fourier transform infrared) and energy dispersive X-ray (EDX) techniques. The catalytic activity and stability of fabricated electrodes towards ethanol oxidation in alkaline media were studied by cyclic voltammetry, linear sweep voltammetry and chronoamperometry measurements. High current density (64.1 mA cm(-2)), low onset potential (-0.725 V) and high electrochemically active surface area (26.27 m(2) g(-1)) were unique features of Pd/PANI-MWCNTs-SnO2/Ti electrode. Other electrochemical tests, Tafel analysis, CO-stripping voltammetry, long-time stability and electrochemical impedance spectroscopy (EIS) indicated that the Pd/PANI-MWCNTs-SnO2/Ti electrode has the best performance for ethanol oxidation in comparison with other prepared electrodes. Therefore, obtained results demonstrated that the Pd/PANI-MWCNTs-SnO2/Ti electrode can be a promising candidate towards ethanol oxidation reaction for use in direct ethanol fuel cells.