Suppression\nof Pt Nanocluster Aggregation and Enhanced\nOxygen Reduction Activity by Heteroatom Doping of Carbon Nanotubes

Increasing\nthe performance of platinum (Pt) catalysts for the oxygen\nreduction reaction (ORR) in polymer electrolyte membrane fuel cells\ncould reduce the amount of this expensive metal that is required.\nPt nanoclusters (NCs) can provide substantially increased ORR activity\nper unit mass of Pt and so are of interest. However, there has been\nno research regarding supports for Pt NCs exhibiting both high specific\nsurface area and high conductivity. The present work improved the\nORR activity and durability of carbon nanotubes by doping with nitrogen\nor sulfur to reduce the level of aggregation of supported Pt NCs.\nPt NCs supported on sulfur-doped carbon nanotubes showed 2.32 times\nhigher activity (425.2 A/g<sub>Pt</sub>) and greater durability compared\nwith those of commercially supported Pt nanoparticle catalysts.