Abstract:

Pd nanoparticles were supported on different types of carbon materials including multiwalled carbon nanotubes (MWCNT) and carbon black prepared by the intermittent microwave heating (IMH) technique. The morphologies and electrochemical properties of the electrocatalysts were characterized. TEMand XRD measurements revealed that the Pd nanoparticles were uniformly dispersed on MWCNT with an average particle size of 4 nm. The cyclic voltammetric, chronopotentiometric, and electrochemical impedance spectroscopic (EIS) experiments indicated that Pd/MWCNT electrocatalyst showed a better performance for methanol oxidation than that of Pt/C in alkaline media. A negative shift over 100 mV of the onset potential for methanol oxidation was found on Pd/MWCNT compared to that on Pt/C. The results indicated that the enhancement in the activity for methanol oxidation on Pd/MWCNT was due to not only the increase in the active surface area but also the synergistic interaction between Pd and MWCNT.

Key words: Methanol oxidation, Carbon nanotube, Pd/MWCNT, Electrocatalyst, Fuel cell