Electrocatalytic Activity of Copper–Palladium Nanopaticles for Formic Acid Oxidation

In this work, the catalytic activity of copper-palladium (Cu-Pd) nanoparticles (NPs) is studied for formic acid oxidation. The Cu-Pd NPs were synthesized in a toluene/water system at room temperature. The synthesis of organic phase containing the metal ions was carried out as follows: the aqueous solutions containing the cooper and palladium metals ions, Cu(NO₃)₂ and PdCl₂. Cu and Pd were mixed in appropriate amounts to obtain aqueous solution with 1:1 molar ratios of Cu:Pd. The toluene solution of hexadecylamine (C₁₆H₃₃NH₂) was added to the Cu and Pd aqueous solution under strong stirring. For the mixture solution, an immediate two-layer separation was produced, with a light yellow organic phase on the top and a yellow tinted aqueous phase on the bottom. Ions were allowed to diffuse gradually into the organic phase by complexing them with the amine. Cu-Pd NPs were characterized by UV-Vis spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and energy dispersive X-ray (EDX) analysis. The catalytic activity of Cu-Pd NPs was evaluated for formic acid oxidation, using the anodic current density. The electrochemical result shows that Cu-Pd NPs present a higher catalytic activity than Pd NPs.