Nitrogen-containing carbon nanotubes as cathodic catalysts for proton exchange membrane fuel cells

Proton exchange membrane fuel cells (PEMFC) comprise a diverse range of fuel cell thought to have future commercial application and transportation. The introduction of nitrogen into carbon nanostructures has created new pathways for the development of non-noble metal electro-catalysts in fuel cells. This review provides insight into the role of nitrogen inclusion into the carbon nanotubes (CNT) and the possible mechanisms involved in oxygen reduction reaction (ORR) activity. The doping effects of nitrogen into CNT on the surface morphology, electronic structures and electrochemical activity are discussed. Catalyst nanoparticles distribution, chemical composition and the incorporation of a binder play crucial roles in the generation of good catalytic activity and high stability in organic electro-catalysts. Synthesize methods for making nitrogen-containing carbon nanostructures and the resultant oxygen reduction reactivity are compared. Finally, stability issues of the N-CNT electrocatalysts are discussed.