HxMoO3-assisted deposition of platinum nanoparticles on MWNTs for electrocatalytic oxidation of methanol

Platinum nanoparticles were loaded on multi-walled carbon nanotubes (MWNTs) by using ethylene glycol as reductant and with the assistance of hydrogen molybdenum bronze (HxMoO3, 0 < x ≤ 2) for the electrocatalytic oxidation of methanol. In this approach, MWNTs were modified by HxMoO3 and used as the support for platinum nanoparticles. The XRD and TEM characterizations indicate that the average particle size of platinum supported by the modified MWNTs (Pt/HxMoO3-modified-MWNTs) is 3.4 nm, smaller than that (4.3 nm) of the platinum supported by the unmodified MWNTs (Pt/MWNTs). The voltammetric and chronoamperometric experiments show that Pt/HxMoO3-modified-MWNTs exhibits better electrocatalytic activity toward methanol oxidation than Pt/MWNTs, although the former has a less platinum loading (4.6 wt%) than the latter (6.0 wt%). The mechanism on the assistance of HxMoO3 to the platinum deposition was discussed.