Catalytic trends of nitrogen doped carbon nanotubes for oxygen reduction reaction.

Replacing the state-of-the-art fuel cell catalyst platinum for a cheaper and abundant alternative would make the hydrogen economy viable. Both nitrogen-doped graphene and nitrogen-doped carbon nanotubes (N-CNT) have been shown to be capable of acting as a metal-free catalyst for the oxygen reduction reaction (ORR). Until now, most of the research has been focused on the nitrogen doping and less on the structure of the nanotubes.