MWCNT-supported PtRu catalysts for the electrooxidation of methanol: Effect of the functionalized support

Functionalized carbonaceous materials have been investigated as supports of PtRu nanoparticles for the electrooxidation of methanol, using such conventional electrochemical methods as cyclic voltammetry and chronoamperommetry and by measurements in a CH3OH/O2-fed single cell. Further, to understand the effect of oxygen-containing groups on the supports in the methanol oxidation reaction (MOR), a kinetic study of the catalyst that has the best behavior in this process has been performed. The study at different temperatures of PtRu nanoparticles supported in multiwall carbon nanotubes (MWCNTs) with a high amounts of functional groups—PtRuCNT-ST—show that there was low CO poisoning during the MOR on this catalyst. The low apparent energy on PtRuCNT-ST in the MOR was attributed to CO diffusion or to the dissociative adsorption of methanol. Both factors had a beneficial effect on the oxygen-containing groups on MWCNTs, facilitating oxidation of the carbonaceous intermediates to CO2 or HCOOH. These findings have been confirmed by studies in a single cell feeding with CH3OH/O2, demonstrating that PtRuCNT-ST is the best-performing anodic electrode.

► The effect of the nanoparticles support in the electrooxidation of methanol has been studied.
► The functional groups on MWCNTs could to be helping in the process.
► PtRuCNT-ST displayed the best behaviour in the MOR.
► Its kinetic study revealed a low CO poisoning during the MOR.
► This catalyst displayed the best behaviour as anode in a methanol single cell.