  Fuel cells offer an alternative to burning fossil fuels, but use platinum as
a catalyst which is expensive and scarce. Cheap, alternative catalysts could
enable fuel cells to become serious contenders in the green energy sector. One
promising class of catalyst for electrochemical oxygen reduction is
iron-containing, nanostructured, nitrogen-doped carbon. The catalytic activity
of such N-doped carbons has improved vastly over the years bringing industrial
applications ever closer. Stoichiometric carbon nitride powder has only been
observed in recent years. It has nitrogen content up to 57% and as such is an
extremely interesting material to work with. The electrochemical activity of
carbon nitride has already been explored, confirming that iron is not a
necessary ingredient for 4-electron oxygen reduction. Here, we synthesize
carbon nitride on a carbon nanotube support and subject it to high temperature
treatment in an effort to increase the surface area and conductivity. The
results lend insight into the mechanism of oxygen reduction and show the
potential for carbon nanotube-supported carbon nitride to be used as a catalyst
to replace platinum in fuel cells.
