Catalysts made of carbon nanotubes dipped in a polymer solution outperform platinum catalysts in fuel cells report Liming Dai and co-workers, Case Western Reserve University, Ohio, USA. The team soaked carbon nanotubes in an aqueous solution of polydiallyldimethylammoniumn chloride. The polymer coated the nanotube surface and pulled an electron partially from the carbon, creating a net positive charge.

Within a fuel cell, the charged material acts as a catalyst for the oxygen-reduction reaction that produces electricity while electrochemically combining hydrogen and oxygen. The unoptimized system was shown to produce as much power as a platinum fuel cell and had greater stability.

Replacement of the platinum in fuel cells with carbon nanotubes would represent a significant reduction in cost.

• Polyelectrolyte Functionalized Carbon Nanotubes as Efficient Metal-free Electrocatalysts for Oxygen Reduction
  S. Wang, D. Yu, L. Dai,
  J. Am. Chem. Soc. 2011.
  DOI: 10.1021/ja1112904