Development of Novel Catalysts by γ-Irradiation-Induced Distribution of Pt-Sn Nanoparticles onto Multiwalled Carbon Nanotubes

We have demonstrated a new, simple and effective technique for the synthesis of Pt, Sn or Pt-Sn nanoparticles supported on thiol-functionalized, multiwalled carbon nanotube (MWNT(SH)) catalysts using gamma-irradiation. The use of gamma-irradiation minimizes the preparation time and produces a clean catalyst, as no additional reducing agents are involved in the preparation. The morphology of the MWNT(SH)/Pt, MWNT(SH)/Sn and MWNT(SH)/Pt-Sn catalysts was examined by field emission transmission electron microscopy (FE-TEM). The Pt-Sn catalyst particles exhibited a core-shell morphology with Pt as the core (15 nm) and Sn as the shell (10 nm). The catalysts showed electro-active behavior towards methanol oxidation, due to the synergistic contribution of MWNT(SH) and the metal or alloy particles.