Multi-walled carbon nanotube supported palladium nanoparticles: Synthesis, characterization and catalytic activity towards methanol electro oxidation in alkaline media

Palladium nanoparticles supported on multi-walled carbon nanotubes (Pd/MWCNTs) have been synthesized using a modified polyol reduction method and its performance in methanol oxidation reactions has been evaluated. The morphology of palladium on MWCNTs was characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The catalytic performance of the synthesized catalyst was examined for methanol oxidation in a N2- saturated solution of 1 M KOH and 1 M CH3OH. Cyclic voltammetry (CV) analysis demonstrated that the Pd/MWCNTs catalyst exhibits lower catalytic activity compared to the commercial Pt/C, but because of its relatively low-cost, the prepared Pd/MWCNTs might be an economically viable alternative for methanol oxidation. The chronoamperometry technique is an effective method to evaluate the electrocatalytic activity and stability of the alcohol oxidation reaction. The chronoamperometry results showed that Pd supported on MWCNT has better long-term stability in comparison to Pt/C which is related to the good dispersion of Pd nanoparticles on the surface of support.